HK1124641B - Composite of metal with resin and process for producing the same - Google Patents

Description

Composite of metal and resin and method for producing same

Technical Field

The present invention relates to a metal-resin composite comprising a metal and a resin composition used for housings of electronic devices, housings of home electric appliances, structural parts, mechanical parts, and the like, and a method for producing the same. More specifically, the present invention relates to a composite of a thermoplastic resin composition and a magnesium alloy substrate produced by various machining processes, which are integrated and laminated, and a method for producing the same, and relates to a composite of a metal and a resin used for structural parts and packaging parts such as various electronic devices, electrical appliances, medical devices, automobiles, trains, airplanes, vehicle-mounted products, and building materials, and a method for producing the same.

Background

A technique of integrating a metal and a synthetic resin is in wide industrial fields such as automobile, home electric appliances, and parts manufacturing industries of industrial equipment, and many adhesives have been developed for this purpose. Among these, a very excellent adhesive is proposed. For example, an adhesive that exhibits its function at room temperature or by heating is used for bonding a metal and a synthetic resin integrally, and this method is a general bonding technique at present.

However, a more rational joining method using no adhesive is also being studied. A method of integrating a high-strength engineering resin without using an adhesive with respect to a light metal such as magnesium, aluminum, or an alloy thereof, or an iron alloy such as stainless steel is an example. For example, the present inventors have proposed a method of injecting a molten resin into a metal part previously inserted into an injection mold to mold a resin portion and simultaneously fixing (joining) the molded article and the metal part (hereinafter, simply referred to as "injection joining").

This invention proposes a manufacturing technique in which a polybutylene terephthalate resin (hereinafter referred to as "PBT") or a polyphenylene sulfide resin (hereinafter referred to as "PPS") is injected into an aluminum alloy to join the aluminum alloy (see, for example, patent document 1). In addition, a bonding technique has been disclosed in which a large hole is provided in an anodized film of an aluminum material, and a synthetic resin is caused to penetrate into the hole and adhere thereto (see, for example, patent document 2).

The principle of this injection joining in the proposal of patent document 1 is as follows: the aluminum alloy is immersed in a dilute aqueous solution of a water-soluble amine compound, and the aluminum alloy is etched finely by the weak alkalinity of the aqueous solution. It was also found that adsorption of amine compound molecules to the surface of the aluminum alloy occurs simultaneously with the immersion. The aluminum alloy having completed this treatment is inserted into an injection molding die, and the molten thermoplastic resin is injected at high pressure.

At this time, the thermoplastic resin and the amine compound molecules adsorbed on the surface of the aluminum alloy come into contact with each other to generate heat. Almost simultaneously with the heat generation, the thermoplastic resin is rapidly cooled by contact with the aluminum alloy kept at the low mold temperature, and the resin crystallized and solidified is set to be slowly solidified and to be buried in the recesses on the surface of the ultra-fine aluminum alloy. Thus, the aluminum alloy and the thermoplastic resin are firmly joined (fixed) without the resin falling off from the surface of the aluminum alloy. That is, when a heat generating reaction occurs, a firm injection joint can be performed. It was confirmed that PBT and PPS which can undergo a heat-generating reaction with an amine compound can be injection-bonded to the aluminum alloy.

[ patent document 1] Japanese patent application laid-open No. 2004-

[ patent document 2] WO 2004/055248A 1

Disclosure of Invention

The present inventors have searched and developed a resin composition suitable for injection bonding in order to make the above-described invention more effective. That is, a technique of providing numerous fine recesses on a metal surface and bonding the recesses has been developed and developed. As a result, it was found that a simple PBT or PPS composition having a linear expansion coefficient matching that of the aluminum alloy is not optimal, and the material properties relating to the crystallinity of both resins are more greatly related to the injection bonding. In another aspect thereof, the present inventors have also focused on the surface layer of the metal being injection bonded. As a result, the crystallinity of PBT or PPS can be understood, and it is inferred that the connection by injection molding may be carried out in addition to the aluminum alloy which has been already elucidated and subjected to the ultra-fine etching. This inference will be described in detail below.

It is considered that there are generally two conditions for the thermoplastic resin to be injection-joined to the metal shaped object. The first is a metal surface layer having a concavo-convex shape on a micrometer level, and further, the surface itself on which the concavo-convex is formed is a hard surface and has a concavo-convex shape as observed on an electron microscope level (with ultra-fine fineness on a nanometer level). If the diameter of the recess is large in the order of micrometers, PBT or PPS can penetrate even without adsorption of amine molecules. Second, the resin is a crystalline resin, which has a high crystallization rate, a hard crystal portion of the resin, and thus has mechanical strength, and is of a size suitable for fixation of the resin, that is, specifically, PBT or PPS. In the injection molding under these two conditions, when the molten resin is rapidly cooled by contact with a metal mold and an insert metal having a low temperature of about 100 ℃ or so lower than the melting point of the resin, the resin can be crystallized and solidified in the recesses on the metal surface. This causes strong bonding (fixation) between the resin and the metal.

Further, as a preferable condition (third condition) in the injection bonding, it can be said that the injection bonding becomes stronger when the above resin composition is modified. That is, since the crystalline resin composition is crystallized and solidified at the time of rapid cooling, the resin composition is improved so that the solidification rate is lowered. In short, even if the temperature is lowered to a temperature lower than the melting point of the resin by quenching, the seed crystal cannot be directly generated from the resin, and the growth and solidification are not performed. The minute time is a time for maintaining the supercooled state and the molten state. It is presumed that: the supercooling time can be delayed by mixing any foreign resin into the resin.

It is estimated that the smallest size of the resin crystal, which is a seed crystal, is about 10nm or more, and even if the resin crystal starts growing from the seed crystal and reaches the entrance of the ultrafine recess having a diameter of 20 to 80nm easily after the growth is completed, the resin crystal is unlikely to penetrate deep. However, if the resin composition is such that the seed crystal is not directly generated during rapid cooling and the subsequent crystal growth is slightly slow, the resin may enter the recesses if the diameter of the recesses is also several hundred nm. Further, if the surface in the concave portion is rough, the resin composition is hard to be separated from the concave portion after being firmly crystallized and solidified, and in this case, stronger bonding can be achieved.

Magnesium alloys are lighter alloys than aluminum alloys, which is the largest feature of magnesium alloys, and on the other hand, are more chemically active than aluminum alloys. After an exposed metal surface is also formed on the magnesium alloy by polishing or the like, a natural oxide layer is generated and there is some degree of stability. However, the stability and the firmness of the natural oxide layer are far inferior to those of the oxide coating layer of the aluminum alloy. For example, in aluminum alloys, if an oil film of a rust inhibitor and a coating film are present on a natural oxide layer, the alloys are stable for ten years or more when left standing in a room without condensation, but in magnesium alloys, the alloys swell or rust in less than 1 year. The water molecules diffused through the oil film and the coating film oxidize magnesium through the natural oxidation layer. In short, when a magnesium alloy is actually used, it is necessary to cover the magnesium alloy with a strong coating film instead of the natural oxide film.

Specifically, magnesium alloys are treated by either conversion treatment or electrolytic oxidation, but conversion treatment is generally used at present. From the practical viewpoint, the present inventors have established a technique for injection-bonding a resin to a magnesium alloy subjected to conversion treatment. Fortunately, the surface of the conversion treated magnesium alloy is covered with a metal oxide, metal carbonate or metal phosphate which is much harder than the substrate as the metal itself. This corresponds to one of the two conditions required for the injection bonding, i.e., the surface is covered with the hard material irregularities.

The present invention has been completed based on the above-described theories, and the following objects are achieved.

The purpose of the present invention is to provide a composite of a metal and a resin, in which a resin layer mainly composed of PBT or PPS can be strongly bonded to a magnesium alloy, and a method for producing the same.

Another object of the present invention is to provide a composite of a metal and a resin, which is obtained by integrating a base material made of magnesium metal having a surface layer which has been subjected to conversion treatment and has excellent corrosion resistance with a resin composition containing PBT or PPS as a main component, and a method for producing the same.

Another object of the present invention is to provide a metal-resin composite having high mass productivity and productivity by molding a thermoplastic resin composition containing PBT or PPS as a main component by injection molding, and a method for manufacturing the same.

In order to achieve the above object, the present invention adopts the following measures.

The gist of the metal-resin composite of the present invention includes: a substrate comprising a magnesium alloy; a surface layer formed on the surface of the magnesium alloy, the surface layer being any one of a metal oxide, a metal carbonate, and a metal phosphate obtained by converting 1 or more selected from chromium, manganese, vanadium, calcium, zinc, strontium, zirconium, titanium, and an alkali metal carbonate into an aqueous solution; and a resin layer which is impregnated into the recessed portion of the surface layer by injection molding, cured and fixed, and which contains a polybutylene terephthalate resin or a polyphenylene sulfide resin as a main component, which is a crystalline thermoplastic resin.

The gist of the method for producing a composite of a metal and a resin according to the present invention includes: a shaping step of shaping a cast product or an intermediate material made of a magnesium alloy by machining to form a shaped part; a conversion treatment step of forming 1 type selected from the group consisting of metal oxides, metal carbonates, and metal phosphates on the surface layer of the shaped part; an injection step of inserting the shaped part having completed the liquid treatment step into an injection molding die and injecting a molten resin composition containing polybutylene terephthalate or polyphenylene sulfide as a main component; and a fixing step of impregnating the recesses of the metal oxide or the metal phosphate by the injection molding and curing the recesses to integrally fix the shaped part and the resin composition.

Hereinafter, each element constituting the present invention will be specifically and specifically described.

[ base Material ]

The substrate as used in the present invention means a metal portion constituting the composite. The base material is a commercially available or publicly known magnesium alloy including an alloy for forging and rolling such as AZ31 and an alloy for casting such as AZ91, which are defined by Japanese Industrial Standards (JIS). If the magnesium alloy is an alloy for casting, a machine part or the like can be used which is obtained by forming a semifinished product into a desired shape by a forming method such as die casting, thixomolding, injection molding or the like, and further machining the semifinished product into a desired shape. Further, as the base material, a commercially available plate material, bar material, square material, pipe material, or the like can be used as the alloy for stretching, and a part formed by subjecting these materials to mechanical processing such as press working, cutting, grinding, or the like can be used.

[ surface layer of substrate (Metal oxide, Metal carbonate, or Metal phosphate) ]

The surface layer as referred to in the present invention means a metal oxide, a metal carbonate or a metal phosphate formed on the surface of a base material made of a magnesium alloy. The material constituting the surface layer preferably has hardness harder than the texture of the base material and has high mechanical strength. In general, since magnesium alloys have a high tendency to ionize their surfaces and are easily corroded and oxidized by moisture in the air, surface treatment is required. Therefore, the following measures are generally adopted: magnesium or a magnesium alloy is immersed in an aqueous solution of a salt or an acid of a different metal, thereby forming a stable layer containing a metal oxide, a metal carbonate, a metal phosphate or the like of a different metal on the surface thereof, and corrosion protection of the internal metal is performed by the presence of the stable layer.

A metal phosphate, metal carbonate or metal oxide layer obtained by an aqueous solution immersion treatment is formed on the surface of the base material of the present invention. These are corrosion-preventing layers for preventing corrosion of internal metals, that is, magnesium alloys which have a high ionization tendency and are easily corroded and oxidized even by moisture in the air are immersed in aqueous solutions of salts or acids of different metals to form stable layers of oxides, carbonates or phosphates of different metals and/or magnesium on the surfaces, and corrosion of internal metals is prevented by the presence of these layers. Such an immersion treatment is referred to in the industry as a conversion treatment for the surface treatment of metals.

The conversion treatment often includes degreasing and chemical etching performed as a pretreatment of the conversion treatment. In the present invention, the "conversion treatment" means a treatment in a narrow sense for producing a corrosion-resistant layer so as not to be mixed with each other, and the treatment such as degreasing and etching performed as a pretreatment for the conversion treatment is referred to as "pretreatment", and the whole including both the pretreatment and the conversion treatment is referred to as "liquid treatment".

The conversion treatment other than chromium is called non-chromate treatment, and manganese-based treatment has been mainly used recently within the limits known by the present inventors (for example, refer to Japanese patent application laid-open Nos. 7-126858 and 2001-123274). Further, a method of forming a layer composed of a composite oxide of aluminum, vanadium, zinc, zirconium, titanium, or the like on the surface as an anti-corrosion layer is also known as a non-chromate treatment (see, for example, japanese patent laid-open No. 2000-199077). Historically, chromating using chromium compounds has been used for a long time as a treatment method excellent in corrosion resistance.

However, since an aqueous chromic acid solution for chromate treatment is used, there is a problem in that it contains 6-valent chromium, which is environmentally problematic, and a conversion treatment method using no chromium has been recently sought. Accordingly, methods using the above-mentioned manganese and other metals have been developed, and recently, a method using a manganese compound has been seen as a substitute for the chromate treatment. The substrate used in the present invention may be a material surface-treated by any of these methods.

According to the results of the studies by the present inventors, more preferable requirements are: (1) sufficient corrosion resistance, (2) unevenness was formed on the surface layer obtained by the conversion treatment, and many crystals were observed on the surface by an electron microscope. In the present invention, both the conditions (1) and (2) are essential, but in the present invention, the consideration is given to the condition (2) in particular. The magnesium or magnesium alloy preferably has a hard and strong surface layer such as a metal oxide, a metal carbonate or a metal phosphate. This is because the injected crystalline thermoplastic resin enters the hard and strong uneven surface layer and is crystallized and solidified, thereby generating a strong bonding force.

The hard and strong surface layer obtained by the conversion treatment preferably has a micro-scale roughness (otherwise referred to as "having a micro-scale roughness"), and if it has a surface shape having a nano-scale roughness on the concave surface, the resin is captured on the surface of the metal, that is, the resin is caught on the roughness of the metal surface layer to generate an anchor effect. Specifically, although observation by an electron microscope is necessary, it is preferably 1 μm²The case of 2 or more plate-like crystals and the case of covering the surface widely with needle-like or rod-like crystals or covering the surface of the substrate by connecting blocks having needle-like or rod-like crystals as the skin were observed. In addition, many circular columns having a diameter of about 10nm and a length of about 100nm can be formed by electron microscope observation. However, the circular column is not limited to the crystal.

Each 1 μm²When about 2 or more plate-like crystals are observed, the plate-like crystals function as the walls of the uneven portion, and are effective as a mechanically strong fixing member for improving the fixing force. On the other hand, when the needle-like or rod-like crystals cover 30% or more of the surface, the fixing member is formed in a natural and strong uneven shape, and it is more effective in improving the injection joining force by securing the hooking with the resin. Next, specific methods for carrying out the respective steps and their viewpoints will be described.

[ surface treatment/pretreatment of magnesium or magnesium alloy ]

The pretreatment in the present invention is a pretreatment for forming a surface layer composed of a metal oxide, a metal carbonate, or a metal phosphate on the surface of a base material composed of a magnesium alloy. The base material made of magnesium or a magnesium alloy is preferably first immersed in a degreasing bath to remove impurities such as oils and cutting adhered thereto by machining. Specifically, it is preferable that a degreasing material for magnesium, which is commercially available, is dissolved in warm water at a concentration specified by a pharmaceutical manufacturer, and the magnesium alloy is immersed in the solution and then washed with clean water. In a general commercial product, the concentration is set to 5 to 10%, the liquid temperature is set to 50 to 80 ℃, and the dipping is carried out for 5 to 10 minutes. Then, the magnesium alloy part is immersed in an acidic aqueous solution to be etched, and the surface layer of the magnesium alloy part is dissolved, thereby removing dirt, and residual oil agent and residual surfactant. The use solution is preferably an organic carboxylic acid having a pH of 2.0 to 5.0, and weakly acidic aqueous solutions such as acetic acid, propionic acid, citric acid, benzoic acid, and phthalic acid can be used.

In addition to high purity magnesium with a magnesium purity close to 100%, magnesium alloys contain various metals. For example, AZ31 and AZ91 contain 3 to 9% of aluminum and about 1% of zinc, and aluminum and zinc are difficult to dissolve in the etching step using a weakly acidic aqueous solution and deposit on the surface as insoluble substances, and therefore, a step of dissolving and removing these deposits is required to achieve cleanliness.

This is a process called "stain removal". In general, the AZ31B, AZ91D, and the like are immersed in a weakly alkaline aqueous solution to dissolve aluminum contaminants (first contaminant treatment), and then immersed in a strongly alkaline aqueous solution to dissolve zinc contaminants (second contaminant treatment). In the first stain treatment described above, a commercially available degreasing material aqueous solution for aluminum alloy may be used in weak alkalinity. The present inventors have conducted a method of immersing the above-mentioned commercially available degreasing agent for aluminum in an aqueous solution at 60 to 80 ℃ at a concentration of 5 to 10% for several minutes. In addition, the second sewage treatment is performed by immersing the sewage in an aqueous solution of sodium hydroxide having a concentration of 15 to 25% at 70 to 80 ℃ for 5 to 10 minutes.

[ surface treatment/conversion treatment of magnesium or magnesium alloy ]

The conversion treatment referred to in the present invention is a treatment for forming a surface layer composed of a metal oxide, a metal carbonate, or a metal phosphate on the surface of a base material composed of a magnesium alloy. After the completion of the pretreatment, a conversion treatment, which may be referred to as a main treatment, is performed in the liquid treatment. The conversion treatment is usually carried out by a two-stage immersion treatment, that is, first, a very short time of immersion in a weakly acidic aqueous solution to conduct fine etching, and then, a conversion treatment method for various magnesium alloys of the prior art is improved and carried out. The fine etching step may be carried out using an organic carboxylic acid having a pH of 2.0 to 6.0, for example, a weakly acidic aqueous solution of acetic acid, propionic acid, citric acid, benzoic acid, phthalic acid, phenol derivative, etc., and the immersion time is preferably as short as 15 to 40 seconds.

The conversion treatment process used in the present invention is basically the same as the conversion treatment known in the art. That is, this conversion treatment method is also a publicly known technique adopted in many patents, and details thereof are omitted. The following methods have also been proposed for the conversion treatment: for example, the corrosion resistance of the magnesium alloy is improved by immersing the magnesium alloy in an aqueous solution or aqueous suspension containing 1 or more metals selected from chromium, manganese, vanadium, calcium, zinc, strontium, zirconium, titanium compounds and alkali metal carbonates to form a metal oxide, metal carbonate or metal phosphate on the surface. On the other hand, the conversion treatment which is actually commercialized is roughly two methods within the limits known by the present inventors: a chromate method in which the surface is covered with chromium oxide or a chromate containing magnesium by immersion in an aqueous solution of chromic acid, or a method in which the surface is covered with a phosphate of manganese by immersion in an aqueous solution of manganese phosphate.

Currently, the use of chromium having a valence of 6 is being worried about from the viewpoint of the influence on the human body, and the latter is the mainstream among the above surface treatments, and is changing to a treatment called a non-chromate method. The conversion treatment is intended by the present inventors to impart corrosion resistance and to form a surface having high mechanical strength in terms of material mechanics at the time of injection bonding. According to the results of the studies by the present inventors, an injection-molded article having a predetermined strength can be obtained while sufficient corrosion resistance is obtained in both the conversion treatment of the type of the above-mentioned patent application and the chromate treatment and non-chromate treatment which have been put into practical use. However, in particular, in the case of a substance having a good injection bonding result, when the metal surface is observed with an electron microscope, a clear microcrystalline structure is observed and a beautiful repeating structure of a nanometer order is observed. In addition, in order to adjust a substance in which many crystals and a beautiful repetitive structure are observed under an electron microscope, a method of performing a fine etching step is preferable.

Specific examples of the conversion treatment step which is considered to be one of the most preferable methods will be described. The magnesium alloy part after the pretreatment is immersed in a 0.1 to 0.5% aqueous solution of citric acid hydrate at about 40 ℃ for 15 to 60 seconds again to perform fine etching, and then washed with ion-exchanged water. Then, an aqueous solution containing 1 to 5% potassium permanganate, 0.5 to 2% acetic acid, and 0.1 to 1.0% sodium acetate hydrate is prepared as a conversion treatment solution at 40 to 60 ℃, the magnesium alloy part is immersed in the aqueous solution for 0.5 to 2 minutes and washed with water, and then dried in a warm air dryer at 60 to 90 ℃ for 5 to 20 minutes. A tawny magnesium alloy part covered with a thin layer of manganese oxide was obtained.

On the other hand, an example of a preferable method for carrying out the present invention by using a chromate treatment method which is generally considered to be the most excellent in corrosion resistance is shown. The magnesium alloy substrate subjected to the pretreatment is immersed in a 0.1 to 0.5% aqueous solution of citric acid hydrate at a temperature of about 40 ℃ for 15 to 60 seconds, subjected to fine etching, and then washed with ion-exchanged water. Then, a 15 to 20% aqueous solution of chromic anhydride (chromium trioxide) is prepared and set to 60 to 80 ℃ as a conversion treatment liquid, the magnesium part subjected to the fine etching is immersed in the conversion treatment liquid for 2 to 4 minutes and washed with water, and the magnesium part is dried in a hot air dryer set to 60 to 90 ℃ for 5 to 20 minutes. The surface of the magnesium alloy member was treated with chromate to obtain a gray-colored base material.

[ resin layer ]

The resin layer constituting the present invention is a crystalline thermoplastic resin, that is, a resin containing PBT or PPS as a main component. Polyamide is also a highly crystalline resin, and is not a resin that cannot be used in the present invention, but is slightly weak in mechanical strength and has water absorption, and therefore, in the present stage, it is not sufficient in terms of reliability from the viewpoint of whether or not the fixing force is maintained for a long period of time, and is not used in the present invention. However, it may be used according to its use. The resin layer referred to in the present invention is a portion formed by injection molding and is indicated by a "layer", but it does not mean a thin material, and is a material having a thickness and a shape.

In order to improve various mechanical properties, the resin layer of the present invention may be blended with a polymer other than PBT or PPS, a filler such as glass fiber or carbon fiber, a modifier, or the like, as necessary, by a conventional method. As the base resin of PBT, various kinds of PBT synthesized for injection molding can be used. On the other hand, the basic resin of PPS may be a linear resin, a resin into which a branched structure is introduced, or a resin which is subjected to heat treatment in an inert gas, but a resin into which a branched structure is introduced or a resin which is subjected to heat treatment in an inert gas is preferable.

[ resin layer (composition of PPS and polyolefin) ]

The resin layer of the present invention mainly uses PBT or PPS, and in the case of using PPS, particularly when a proper amount of polyolefin-based resin is added, the fixing strength becomes stronger. The reason for this is presumed to be that the crystallization rate at the time of rapid cooling is lowered by addition of an appropriate amount of the polyolefin-based resin. As a result, it is understood that the resin is sufficiently impregnated into the recesses forming the conversion-treated surface, and then crystallized and solidified, and the flow of the molten resin before solidification is also caused to correspond to the nano-scale unevenness on the surfaces of the recesses to some extent, and as a result, sliding and dropping are also stopped, and the fixing strength is improved.

The resin composition comprising PPS containing the polyolefin resin used in the present invention is preferably a resin component composition comprising PPS70 to 97 wt% and the polyolefin resin 3 to 30 wt%. When a composite having excellent fixing properties is obtained, a resin component composition containing PPS80 to 97 wt% and a polyolefin resin 3 to 20 wt% is more preferable. When the PPS is less than 65 wt% or exceeds 97 wt%, the resulting composite is inferior in the adhesion between the substrate and the resin layer.

The PPS may be in the category of PPS, and is preferably one having a melt viscosity of 100 to 30,000 poises because of excellent moldability in the resin composition. The melt viscosity was measured by a high performance flow tester (high performance flow tester) loaded with a die (die) having a diameter of 1mm and a length of 2mm under conditions of a measurement temperature of 315 ℃ and a load of 10 kg. The PPS may be PPS substituted with an amino group, a carboxyl group, or the like, or PPS copolymerized with trichlorobenzene or the like at the time of polymerization.

Further, any of linear PPS, PPS introduced with a branched structure, and PPS heat-treated in an inert gas can be used. The PPS may be subjected to a deionization treatment (acid cleaning, hot water cleaning, or the like) or a cleaning treatment with an organic solvent such as acetone before or after the heat curing, whereby impurities such as ions and oligomers are reduced, or may be subjected to a heat treatment in an oxidizing gas after the polymerization reaction is completed to be cured.

The polyolefin-based resin is a generally known ethylene-based resin, propylene-based resin, or the like, and may be a commercially available resin. Among them, maleic anhydride-modified ethylene copolymers, glycidyl methacrylate-modified ethylene copolymers, glycidyl ether-modified ethylene copolymers, ethylene-alkyl acrylate copolymers and the like are preferable from the viewpoint of obtaining a composite excellent in adhesiveness in particular.

Examples of the maleic anhydride-modified ethylene copolymer include: maleic anhydride graft-modified ethylene copolymers, maleic anhydride-ethylene copolymers, ethylene-acrylate-maleic anhydride terpolymers, and the like. Among them, an ethylene-acrylic ester-maleic anhydride terpolymer is preferable from the viewpoint of obtaining a particularly excellent composite, and specific examples of the ethylene-acrylic ester-maleic anhydride terpolymer include "ボンダイン (product name) (manufactured by アルケマ company, kyoto city, japan)" and the like.

Examples of the glycidyl methacrylate-modified ethylene copolymer include: among them, glycidyl methacrylate-ethylene copolymer is preferable from the viewpoint of obtaining a particularly excellent composite, and specific examples of the glycidyl methacrylate-ethylene copolymer include "ボンドフア - スト (product name) (manufactured by sumitomo chemical company, tokyo central district, japan)" and the like.

Examples of the glycidyl ether-modified ethylene copolymer include: specific examples of the ethylene-alkyl acrylate copolymer include "ロトリル (trade name)" (manufactured by アルケマ, Kyoto Tokyo City, Japan). In the composite of the present invention, from the viewpoint of providing a composite having more excellent adhesion between the substrate and the resin layer, the resin composition is preferably a composition obtained by mixing 0.1 to 6 parts by weight of a polyfunctional isocyanate compound and/or 1 to 25 parts by weight of an epoxy resin with 100 parts by weight of the total of resin components including 3 to 30% by weight of the polyolefin resin and 3 to 97% by weight of PPS 70.

As the polyfunctional isocyanate compound, non-block type or block type polyfunctional isocyanate compounds commercially available can be used. Examples of the polyfunctional non-blocked isocyanate compound include: 4, 4 '-diphenylmethane diisocyanate, 4' -diphenylpropane diisocyanate, tolylene diisocyanate, phenylene diisocyanate, bis (4-isocyanatophenyl) sulfone, and the like. Further, the polyfunctional block-type isocyanate compound is: a polyfunctional block-type isocyanate compound which has 2 or more isocyanate groups in a molecule and is rendered inert at ordinary temperature by reacting the isocyanate groups with a volatile active hydride. The type of the polyfunctional block isocyanate compound is not particularly limited, and generally, the polyfunctional block isocyanate compound has a structure in which an isocyanate group is masked with a blocking agent such as an alcohol, a phenol, e-caprolactam, an oxime, or an active methylene compound. Examples of the polyfunctional block isocyanate include "ダケネ - ト (trade name) (manufactured by Sanjing chemical polyurethane Co., Tokyo, Japan)".

As the epoxy resin, a known epoxy resin such as a bisphenol a type epoxy resin (エピコ - ト) (trade name) (manufactured by tokyo, japan epoxy resin corporation) or a cresol novolac type epoxy resin (Epikuron (trade name) (manufactured by tokyo, japan ink chemical industry corporation) can be generally used.

[ resin layer (composition of PBT and PET)

The resin component of the resin layer of the present invention may be a composition in which PBT and polyethylene terephthalate (PET) are mixed. The appropriate mixing ratio is PBT 65-100 wt% and PET 0-35 wt%.

[ Filler ]

The resin used in the resin layer of the present invention uses a polybutylene terephthalate resin or a polyphenylene sulfide resin, which is a thermoplastic resin having crystallinity, as a main polymer, and a filler may be mixed with these polymers for the reason of improvement of mechanical properties and the like. The mixing ratio of the filler is preferably 1 to 200 parts by weight based on 100 parts by weight of the total resin component of the polyphenylene sulfide resin and the polyolefin resin or 100 parts by weight of the total resin component of the polybutylene terephthalate resin and the polyethylene terephthalate resin. Examples of the filler include fibrous fillers, granular fillers, and plate fillers. Examples of the fibrous filler include glass fibers, carbon fibers, and aramid fibers, and specific examples of the glass fibers include chopped fibers having an average fiber diameter of 6 to 14 μm. Examples of the plate-like and particulate filler include: ground products of calcium carbonate, mica, glass flakes, glass spheres, magnesium carbonate, silica, talc, clay, carbon fibers, and aramid fibers, and the like. The filler is preferably a filler treated with a silane coupling agent or a titanate coupling agent.

[ method for producing composite ]

The composite of the present invention is preferably produced by a method in which a base material made of a magnesium alloy is inserted into an injection molding die, and then the die is closed to inject a resin, that is, an injection joining method, and preferred production examples are described below. The composite is produced by preparing an injection molding die, opening the die, inserting the magnesium alloy substrate obtained by the conversion treatment such as the above-mentioned treatment from one side thereof, closing the die, injecting a thermoplastic resin composition composed of a resin component containing PBT or PPS, curing the composition, opening the die, and demolding the cured composition.

The injection conditions are explained below. The mold temperature is preferably 100 ℃ or higher, and more preferably 120 ℃ or higher, because it has little influence on the strength of the resin particularly after curing of the resin and the production efficiency of the composite is excellent. On the other hand, the injection temperature, injection pressure, and injection speed are not changed from the usual injection molding conditions, and if necessary, the injection speed and injection pressure are preferably higher.

As described above in detail, the composite of the present invention can be integrated with the resin composition part without peeling off the substrate made of a magnesium alloy. In addition, since the composite has a metal oxide, a metal carbonate, or a metal phosphate formed on the surface layer of the base material, the composite is also excellent in corrosion resistance. Further, by molding a thermoplastic resin composition containing PBT or PPS as a main component by injection molding, a composite body including a base material made of a magnesium alloy and a resin layer can be produced with high mass productivity and high productivity.

Drawings

Fig. 1 is a structural view of an injection molding die schematically showing a process of manufacturing a composite of a magnesium plate piece and a resin composition.

Fig. 2 is an external view schematically showing a single body of a composite of a magnesium plate piece and a resin composition.

FIG. 3 is a photograph of a surface of an AZ31B magnesium alloy having an average metal crystal grain size of 7 μm or less, which is obtained by using an acetic acid aqueous solution as a coarse etchant and dilute nitric acid as a fine etchant, and further performing a conversion treatment of manganese phosphates.

FIG. 4 is a photograph of a surface of an AZ31B magnesium alloy having a metal crystal grain size of 7 μm or less, which is obtained by using an acetic acid aqueous solution as a coarse etchant and citric acid as a fine etchant, and further performing a potassium permanganate conversion treatment.

FIG. 5 is a photograph of a surface of an AZ31B magnesium alloy having an average grain size of 7 μm of metal crystals obtained by using an acetic acid aqueous solution as a coarse etchant and dilute nitric acid as a fine etchant and further performing a conversion treatment with potassium carbonate.

FIG. 6 is a photograph of a surface of AZ31B magnesium alloy (manufactured by Nippon Metal industries, Tokyo, Japan) having an average grain size of 7 μm and having been subjected only to degreasing treatment.

Description of the symbols

1 … magnesium alloy plate

2 … Movable side form

3 … fixed side form

4 … resin composition

5 … pinhole type gate

6 … Joint face

7 … Complex

Detailed Description

Embodiments of the present invention will be described below with reference to examples. Fig. 1 and 2 are diagrams common to the respective embodiments. Fig. 1 is a die structure diagram schematically showing an injection molding die including a movable-side die plate, a fixed-side die plate, and the like. Fig. 2 shows the appearance of a composite 7 in which the base material 1 and the resin composition 4 are integrally bonded by the injection mold.

A magnesium alloy sheet 1 processed into a predetermined shape is inserted between a movable mold plate 2 and a fixed mold plate 3, and a molten resin composition 4 is injected from a nozzle and injected into a cavity through a pin-hole gate 5. The resin composition 4 is fixed to a bonding surface 6 having fine recesses formed on the surface of the magnesium alloy sheet 1, and a composite 7 is produced in which the two are integrated. In the following examples, the fixing force was confirmed by measuring the fixing strength of the composite 7 produced in each example by drawing the magnesium alloy sheet 1 and the resin composition 4, applying a shear stress to the joining surface 6, and measuring the breaking strength.

[ examples ]

The following describes embodiments of the present invention in detail. As a premise, evaluation, measurement methods and measurement machine materials used for evaluation and measurement of the composite obtained in the examples described below are shown below.

[ evaluation and measurement methods and measurement of machine Material ]

(a) Melt viscosity measurement of resin

In order to measure the melt viscosity of a resin, a known high flow tester is used as a device for measuring the melt viscosity and the flow property of various thermoplastic and thermosetting plastics. The melt viscosity was measured at a measurement temperature of 315 ℃ and a load of 0.98MPa (10kgf) using a high flow tester "CFT-500 (trade name)" loaded with a mold having a diameter of 1mm and a length of 2mm (manufactured by Shimadzu corporation, Kyoto, Japan).

(b) X-ray photoelectron analyzer (XPS observation)

One of the surface observation methods is to irradiate a sample with X-rays to analyze the energy of photoelectrons emitted from the sample, and observe the sample with a photoelectron analyzer (XPS observation) that performs qualitative analysis of elements or the like. The photoelectron analyzer used was "AXIS-Nova (trade name)" (manufactured by Kratos Analytical Co., Ltd./Shimadzu corporation, UK) in a form in which a surface having a logarithmic μm diameter was observed in a range of several nm in depth.

(c) Observation with an electron microscope

An electron microscope mainly used for observation of the substrate surface was used. The electron microscope was observed at 1 to 2KV using a Scanning Electron Microscope (SEM) of "S-4800 (trade name) (manufactured by Hitachi, Tokyo, Japan)" and "JSM-6700F (trade name) (manufactured by Nippon electronics, Tokyo, Japan)".

(d) Observation with scanning probe microscope

The above microscope mainly used for observing the surface of the substrate is also used. This microscope is a scanning probe microscope that scans the surface of a substance by moving a probe whose tip is removed, and observes the surface state while enlarging the surface state. As the scanning probe microscope, "SPM-9600 (trade name) (manufactured by shimadzu corporation, kyoto, japan)" was used.

(e) Measurement of bonding Strength of composite

Tensile stress the composite 7 was stretched by a tensile tester to be loaded with a shear force, and the breaking force at the time of breaking was set as a shear stress. The tensile testing machine used "モデル 1323 (trade name) (manufactured by アイコ - エンジニヤリング, Tokyo, Japan)" to measure the shear force at a tensile rate of 10 mm/min.

(f) Salt spray test

A salt spray test was performed to test the corrosion resistance of the composite of the present invention. This test is a salt water spray test "SPT-90 (manufactured by スガ testing machine company, tokyo, japan)" which is one of material testing machines that test materials for corrosion resistance, deterioration, and the like by spraying salt water.

[ preparation example 1 of PPS composition ]

Production example 1 of PPS shows a production example in which PPS and a polyolefin-based resin are mixed. Na was added to a 50 liter-capacity reaction vessel equipped with a stirrer₂S·2.9H₂O6.214 g and N-methyl-2-pyrrolidone (17,000 g) were gradually heated to 205 ℃ while stirring under a nitrogen stream, and 1355g of water was distilled off. After the system was cooled to 140 ℃, 7160g of p-dichlorobenzene and 5000g of N-methyl-2-pyrrolidone were added, and the system was sealed under a nitrogen stream. The system was heated to 225 ℃ over 2 hours, and after polymerizing at 225 ℃ for 2 hours, it was heated to 250 ℃ over 30 minutes, and further polymerized at 250 ℃ for 3 hours.

After completion of the polymerization, the mixture was cooled to room temperature, and the polymer was separated by a centrifugal separator. The polymer was repeatedly washed with warm water, and the solid content was dried at 100 ℃ overnight, whereby PPS having a melt viscosity of 280 poise (hereinafter referred to as PPS (1)) was obtained. This PPS (1) was further cured at 250 ℃ for 3 hours under a nitrogen atmosphere to obtain PPS (hereinafter referred to as PPS (2)). The obtained PPS (2) had a melt viscosity of 400 poise.

6.0kg of the obtained PPS (2), 1.5kg of an ethylene-acrylic ester-maleic anhydride terpolymer (trade name: ボンダイン TX 8030) (manufactured by アルケマ Co., Kyoto City, Japan), and 0.5kg of an epoxy resin (trade name: Epigot epoxy resin 1004) (manufactured by Tokyo, Japan epoxy resin Co., Ltd., Japan) were previously mixed in a tumbler. Then, a glass fiber having an average fiber diameter of 9 μm and a fiber length of 3mm "RES 03-TP91 (trade name) (manufactured by Toshiba machine, Toshiga prefecture, Japan)" was fed from a side feed port by means of a twin-screw extruder "TEM-35B (trade name)", so that the amount of the glass fiber added was 20% by weight, and melt-mixed at a cylinder temperature of 300 ℃ to obtain a pelletized PPS composition (1). The PPS composition (1) is a resin composition in which a polyolefin resin accounts for 20% of the total resin components, and an epoxy resin accounts for 7 parts when the total resin components is set to 100 parts. The obtained PPS composition (1) was dried at 175 ℃ for 5 hours.

[ preparation example 2 of PPS composition ]

PPS composition (1) obtained in preparation example 1 of a PPS composition was cured at 250 ℃ for 3 hours in an oxygen atmosphere to obtain PPS (hereinafter referred to as PPS (3)). The melt viscosity of the obtained PPS (3) was 1800 poise. 5.98kg of the obtained PPS (3) and 0.02kg of polyethylene (trade name: ニポロンハ - ド 8300A) (manufactured by Tokyo, Japan) were mixed in advance uniformly in a tumbler. Then, a glass fiber "RES 03-TP 91" having an average fiber diameter of 9 μm and a fiber length of 3mm was fed from a side inlet by means of the above-mentioned twin-screw extruder "TEM-35B" (front outlet) so that the amount of the glass fiber added was 40% by weight, and melt-kneaded at a cylinder temperature of 300 ℃ to obtain a pelletized PPS composition (2). The composition is a resin composition in which the polyolefin resin accounts for 0.3% of the total resin components. The obtained PPS composition (2) was dried at 175 ℃ for 5 hours.

[ preparation example 3 of PPS composition ]

7.2kg of PPS (2) obtained in preparation example 1 of the PPS composition and 0.8kg of a glycidyl methacrylate-ethylene copolymer "ボンドフア - スト E (manufactured by Sumitomo chemical Co.)" were mixed in advance uniformly by means of a tumbler. Then, a glass fiber "RES 03-TP 91" having an average fiber diameter of 9 μm and a fiber length of 3mm was fed from a side feed port by means of a twin-screw extruder "TEM-35B" (front-end discharge) so that the amount of the feed was 20% by weight, and melt-kneaded at a cylinder temperature of 300 ℃ to obtain a pelletized PPS composition (3). The composition is a resin composition in which a polyolefin resin accounts for 10% of the total resin components. The obtained PPS composition (3) was dried at 175 ℃ for 5 hours.

[ preparation example 4 of PPS composition ]

4.0kg of PPS (2) obtained in preparation example 1 of a PPS composition and 4.0kg of an ethylene-acrylic ester-maleic anhydride terpolymer (trade name: ボンダイン TX 8030) (manufactured by アルケマ Co., Kyoto city, Japan) were previously mixed in a tumbler. Then, a glass fiber "RES 03-TP 91" having an average fiber diameter of 9 μm and a fiber length of 3mm was fed from a side feed port by means of a twin-screw extruder "TEM-35B" (front-end discharge) so that the amount of the feed was 20% by weight, and melt-kneaded at a cylinder temperature of 300 ℃ to obtain a pelletized PPS composition (4). The composition is a resin composition in which a polyolefin resin accounts for 50% of the total resin components. The obtained PPS composition (4) was dried at 175 ℃ for 5 hours.

[ preparation example 5 of PBT composition ]

A commercially available PBT resin "トレコン 1101G45 (manufactured by Tokyo, Japan)" and a PET resin were extruded using a twin-screw extruder "TEM-35B" (previously obtained), to obtain a PBT composition (1) containing PBT 47% and 38% glass fibers. The PBT composition (1) is a resin composition in which PET accounts for 24% of the total resin components. The resulting composition was dried at 130 ℃ for 5 hours.

[ example 1]

A0.8 mm thick AZ31B magnesium alloy (manufactured by Nippon Metal industries, Tokyo, Japan) having a final surface processed to a wet finish (wet) and a mean metal crystal grain size of 7 μm was used. The magnesium alloy sheet was cut into rectangular pieces of 18mm × 45mm (0.8mm in thickness) to prepare a magnesium alloy sheet 1. A through hole was opened at the end of the magnesium alloy sheet 1, and a copper wire coated with ethylene dichloride was passed through ten magnesium alloy sheets 1, and the copper wire was bent in such a manner that the magnesium alloy sheets 1 were not overlapped with each other, and all the magnesium alloy sheets 1 were hung.

A commercially available degreasing agent for magnesium alloy "クリ - ナ -160 (trade name) (manufactured by メルテツクス, Tokyo, Japan)" was put into water in a degreasing bath to prepare an aqueous solution having a concentration of 10% at 75 ℃. The alloy sheet was immersed in the solution for 5 minutes, and sufficiently washed with water. Next, a 2% acetic acid aqueous solution set to 40 ℃ was prepared in another tank, and the alloy piece was immersed in the aqueous solution for 2 minutes and sufficiently washed with water. Black dirt is attached. Next, a 7.5% aqueous solution of a degreasing agent for aluminum alloy "NE-6 (trade name) (manufactured by メルテツクス, Tokyoto, Japan) set at 75 ℃ was prepared in another tank, and the solution was immersed for 5 minutes and sufficiently washed with water. The phenomenon that the aluminum component in the dirt can be dissolved by the weak alkalinity of the liquid can be seen. Subsequently, a 20% sodium hydroxide aqueous solution set at 75 ℃ was prepared in another tank, and the alloy piece was immersed in the aqueous solution for 5 minutes and sufficiently washed with water. It is assumed that the solution dissolves the zinc component in the dirt. Subsequently, the mixture was immersed in a 2% nitric acid aqueous solution at 40 ℃ for 1.5 minutes, which was prepared in another tank, and sufficiently washed with water.

Subsequently, a 45 ℃ manganese phosphate-based non-chromate conversion treatment solution was prepared in another tank. Specifically, an aqueous solution containing 2.5% manganese bisphosphate, 2.5% 85% phosphoric acid, and 2% triethylamine was prepared, immersed for 5 minutes, sufficiently washed with water, and dried in a hot air dryer set at 60 ℃ for 10 minutes. After drying, the copper wire was pulled out from the magnesium alloy sheet on a clean aluminum foil, finished and packed, and then put into a polyethylene bag, sealed and stored. At this time, the finger does not touch the surface for bonding (the end opposite to the side where the through-hole is opened) or the like.

After two days, 1 of them was observed with an electron microscope. Many plate-like crystals were visible on the surface, and further, amorphous matters were visible. The plate-like crystals form voids having a length of 600 to 400nm and a depth of 500nm or more. The number of plate-like crystals that can be observed per 1 μm is 1 to 5, depending on the location. Watch with watchThe image of the face is shown in an electron micrograph (see fig. 3). The remaining magnesium alloy sheet 1 was taken out one day later, and one end having the through-hole was pinched by a hand so as not to allow adhesion of oil components and the like, and inserted into an injection mold set at 140 ℃. The mold was closed, and a PBT resin composition "タフペツト G1030 (trade name) (manufactured by Mitsubishi レイヨン, Tokyo, Japan) containing 30% of a glass fiber was injected at an injection temperature of 260 ℃. The mold temperature was 140 ℃ to obtain 20 integrated composites shown in FIG. 2. The size of the resin part is 10mm × 45mm × 5mm, and the joint surface 6 is 0.5cm of 10mm × 5mm²。

Tensile breaking tests were carried out on 4 composites on the day of formation, resulting in an average shear force of 11.8 MPa. On the day of molding, 5 composites were put into a hot air dryer at 150 ℃ to be annealed for 1 hour, and further subjected to a tensile test one day later, and the average shear fracture stress was measured to be 11.9 MPa. Paint "オ - マツク/シルバ - メタリツク (trade name)" (manufactured by osaka, bridge chemical industries, japan) was applied to 10 remaining integrated products at a set thickness of 10 μm, and then sintered at 170 ℃x30 minutes. After 8 hours of brine spraying at room temperature using 1% brine, washing with water and drying were carried out, and no abnormality was observed in appearance.

[ example 2]

A0.8 mm thick AZ31B alloy sheet having an average metal crystal grain size of 7 μm was obtained. Cut into rectangular pieces in the same manner as in example 1, and immersed in a 10% aqueous solution of a degreasing agent "クリ - ナ -160" at 75 ℃ for 5 minutes, followed by sufficient washing with water. Next, a 2% acetic acid aqueous solution set to 40 ℃ was prepared in another tank, and the magnesium alloy sheet 1 was immersed in the aqueous solution for 2 minutes and sufficiently washed with water. Black dirt is attached. Next, a 7.5% aqueous solution of a degreasing agent for aluminum alloy "NE-6 (trade name) (manufactured by メルテツクス, Tokyoto, Japan) set at 75 ℃ was prepared in another tank, and the solution was immersed for 5 minutes and sufficiently washed with water. Subsequently, a 20% sodium hydroxide aqueous solution set at 75 ℃ was prepared in another tank, and a set of the magnesium alloy sheets 1 was immersed in the aqueous solution for 5 minutes and sufficiently washed with water. The pretreatment was carried out in the same manner as in example 1.

Subsequently, the plate was immersed in a 0.5% citric acid aqueous solution prepared in another tank at 40 ℃ for 15 seconds, and washed with water. Then, an aqueous solution containing 3% potassium permanganate, 1% acetic acid, and 0.5% sodium acetate was prepared, heated to 45 ℃, and immersed for 1 minute, followed by sufficient water washing. Brown and covered with manganese dioxide. Drying in a warm air drier heated to 60 deg.C for 10 min, taking out copper wires from magnesium alloy plate 1 on clean aluminum foil, packaging, placing in polyethylene bag, and sealing. In this operation, the finger does not contact the surface to be joined (the end opposite to the side where the through-hole is opened).

After two days, 1 of them was observed by an electron microscope, and as a result, 80 to 120nm diameter spherical objects in which fine needle-like crystals were formed were aggregated, and they were aggregated and bonded to each other to form large periodic irregularities having a period of 0.5 to 1 μm and a depth of a concave portion of 0.3 to 1 μm. The number of the spherical objects is 90-120 per 1 μm square. Fig. 4 shows a photograph thereof. Then, the remaining magnesium alloy sheet 1 was taken out one day later, and one end having the through-hole was pinched by a hand so as not to cause adhesion of oil or the like, and inserted into an injection mold set at 140 ℃. Exactly the same operation as in example 1 was carried out to obtain 10 integrated composites shown in FIG. 2. The sheet was annealed in a hot air drier at 150 ℃ for 1 hour on the day of molding, and further subjected to a tensile test one day later, and the average shear force was 11.6 MPa.

[ example 3]

A0.8 mm thick AZ31 alloy sheet having an average metal crystal grain size of 7 μm was obtained. The rectangular pieces were cut in the same manner as in example 1, and immersed in a 10% aqueous solution of a degreasing agent "クリ - ナ -160" set at 75 ℃ for 5 minutes, followed by sufficient washing with water. Next, a 2% acetic acid aqueous solution set to 40 ℃ was prepared in another tank, and the magnesium alloy sheet 1 was immersed in the aqueous solution for 2 minutes and sufficiently washed with water. Black dirt is attached. Subsequently, a 7.5% aqueous solution of a degreasing agent for aluminum alloy "NE-6 (trade name)" set at 75 ℃ was prepared in another tank, and the solution was immersed for 5 minutes and sufficiently washed with water. Subsequently, a 20% sodium hydroxide aqueous solution set at 75 ℃ was prepared in another tank, and a set of the magnesium alloy sheets 1 was immersed in the aqueous solution for 5 minutes and sufficiently washed with water. The pretreatment was carried out in the same manner as in example 1.

Subsequently, the plate was immersed in a 0.5% citric acid aqueous solution prepared in another tank at 40 ℃ for 15 seconds, and washed with water. Then, the substrate was immersed in an aqueous solution containing 0.12% zirconium acetylacetonate and 0.05% aqueous solution of fluorinated titanic acid at 40% and set at 60 ℃ for 2 minutes, and sufficiently washed with water. Drying in a hot air dryer set at 60 deg.C for 10 min. The copper wire was pulled out from the magnesium alloy sheet 1 on a clean aluminum foil, and the aluminum foil was finished and packed, and then the package was put into a polyethylene bag and sealed for storage. In this operation, the finger does not contact the surface to be joined (the end opposite to the side where the through-hole is opened).

Then, the remaining magnesium alloy sheet 1 was taken out one day later, and one end having the through-hole was pinched by a hand so as not to cause adhesion of oil or the like, and inserted into an injection mold set at 140 ℃. Exactly the same operation as in example 1 was carried out to obtain 10 integrated composites shown in FIG. 2. The resultant was annealed in a hot air drier at 150 ℃ for 1 hour on the day of molding, and further subjected to a tensile test after one day to determine that the average shear force was 7.7MPa (78 kgf/cm)²)。

[ example 4]

A0.8 mm thick AZ31 alloy sheet having an average metal crystal grain size of 7 μm was obtained. The rectangular pieces were cut in the same manner as in example 1, and immersed in a 10% aqueous solution of a degreasing agent "クリ - ナ -160" set at 75 ℃ for 5 minutes, followed by sufficient washing with water. Next, a 2% acetic acid aqueous solution set to 40 ℃ was prepared in another tank, and the magnesium alloy sheet 1 was immersed in the aqueous solution for 2 minutes and sufficiently washed with water. Black dirt is attached. Subsequently, a 7.5% aqueous solution of a degreasing agent for aluminum alloy "NE-6 (trade name)" set at 75 ℃ was prepared in another tank, and the solution was immersed for 5 minutes and sufficiently washed with water. Subsequently, a 20% sodium hydroxide aqueous solution set at 75 ℃ was prepared in another tank, and a set of the magnesium alloy sheets 1 was immersed in the aqueous solution for 5 minutes and sufficiently washed with water. The pretreatment was carried out in the same manner as in example 1.

Subsequently, the plate was immersed in a 0.5% citric acid aqueous solution prepared in another tank at 40 ℃ for 15 seconds, and washed with water. Then, the steel sheet was immersed in an aqueous solution containing 2% of zinc acetylacetonate, 1% of a 24% aqueous solution of titanium sulfate, and 0.1% of diammonium fluorozirconate at 70 ℃ for 5 seconds, and sufficiently washed with water. Drying in a hot air drier set at 60 deg.C for 10 min, taking out copper wires from the magnesium alloy sheet 1 on clean aluminum foil, finishing, packaging, placing in polyethylene bag, and sealing for storage. In this operation, the finger does not come into contact with the surface to be joined (the end opposite to the side where the through-hole is opened).

Then, the remaining magnesium alloy sheet 1 was taken out one day later, and one end having the through-hole was pinched by a hand so as not to cause adhesion of oil or the like, and inserted into an injection mold set at 140 ℃. Exactly the same operation as in example 1 was carried out to obtain 10 integrated composites shown in FIG. 2. On the day of molding, the molded article was put into a hot air dryer at 150 ℃ for 1 hour for annealing, and after one day, the molded article was further subjected to a tensile test, whereby an average shear force was measured to be 6.9 MPa.

[ example 5]

A0.8 mm thick AZ31B alloy sheet having an average metal crystal grain size of 7 μm was obtained. Rectangular chips were cut in the same manner as in example 1, and subjected to pretreatment including degreasing. The pretreatment method was the same as in examples 1 to 4. Subsequently, the mixture was immersed in a 0.25% aqueous solution of hydrated citric acid at 40 ℃ for 30 seconds, which was prepared in another tank, and washed with water. Then, the magnesium alloy sheet was immersed in an aqueous solution containing 20% chromic acid and set at 75 ℃ for 5 minutes, and sufficiently washed with water. Then, the magnesium alloy sheet was dried in a hot air dryer set at 60 ℃ for 10 minutes, and copper wires were taken out of the magnesium alloy sheet on a beautiful aluminum foil, and the magnesium alloy sheet was conditioned and packed, and further placed in a polyethylene bag, and sealed and stored. In this operation, the finger does not contact the surface to be joined (the end opposite to the side where the through-hole is opened).

After one day, 1 was observed with ESCA. Significant amounts of chromium and oxygen were observed. The main component can be seen as a complex with a chromium oxide or hydroxide having a valence of 3. The magnesium alloy piece was taken out one day later, and one end having the through-hole was pinched by a hand so as not to allow oil and the like to adhere thereto, and was inserted into an injection mold set at 140 ℃. Exactly the same operation as in example 1 was carried out to obtain 20 integrated composites 7 shown in FIG. 2. The resultant was directly put into a hot air dryer at 150 ℃ for 1 hour for annealing, and after one day, further tensile test was carried out to obtain an average shear force of 6.6 MPa. Paint "オ - マツク/シルバ - メタリツク (trade name)" was applied to the remaining 10 integrated products at a set thickness of 10 μm, and sintered at 170 ℃ for 30 minutes. The spray was carried out using 5% saline at 35 ℃ for 8 hours, and the spray was washed with water and dried, but no abnormality was observed in appearance.

[ example 6]

A magnesium alloy AZ31B (manufactured by Tokyo, Japan Metal industries, Ltd.) having an average metal crystal grain size of 7 μm or less and a thickness of 0.8mm, which was finally subjected to wet polishing, was cut into rectangular pieces having the same shape as in example 1, and subjected to a pretreatment including degreasing. The pretreatment method was the same as in examples 1 to 5. Subsequently, the plate was immersed in a 0.25% citric acid aqueous solution prepared in another tank at 40 ℃ for 30 seconds, and washed with water. Then, the plate was immersed in an aqueous solution containing 1% potassium carbonate and set at 70 ℃ for 5 minutes, and sufficiently washed with water. Drying in a hot air drier set at 60 deg.C for 10 min, taking out copper wires from the magnesium alloy sheet on clean aluminum foil, finishing, packaging, placing in polyethylene bag, and sealing for storage. In this operation, the finger does not contact the surface to be joined (the end opposite to the side where the through-hole is opened).

After one day, 1 was observed with an electron microscope. The photograph of FIG. 5 shows the results. The rod-like crystals which are staggered become beautiful crystals in a mesh shape. On the other hand, in the analysis by ESCA, trace amounts of aluminum, zinc and silicon were observed in addition to magnesium, oxygen and carbon. Since carbon was confirmed to be not a trace amount, magnesium carbonate was presumed to be a main component of the surface layer. After one day, the remaining magnesium alloy piece was taken out, and one end having the through-hole was pinched by a hand so as not to allow oil or the like to adhere thereto, and the magnesium alloy piece was inserted into an injection mold set to 140 ℃. Injection molding was carried out in exactly the same manner as in example 1 to obtain 20 integrated composites 7 shown in FIG. 2. On the day of molding, the molded article was put into a hot air dryer at 150 ℃ for 1 hour for annealing, and after one day, the molded article was further subjected to a tensile test, and an average shear force was measured to be 7.0 MPa.

[ example 7]

Exactly the same procedure as in example 1 was carried out, using a 0.8mm thick sheet of AZ31B magnesium alloy (manufactured by Nippon metals Co.) having an average metal crystal grain size of 7 μm or less, and carrying out pretreatment. Then, the mixture was immersed in a 0.25% citric acid aqueous solution prepared in another tank at 40 ℃ for 30 seconds, and washed with water. Then, the steel sheet was immersed in an aqueous solution containing 1% calcium nitrate hydrate, 1% strontium nitrate hydrate, 0.05% sodium chloride and 0.95% 80% phosphorus at 65 ℃ for 10 minutes, and sufficiently washed with water. Drying in a hot air drier set at 60 deg.C for 10 min, taking out copper wires from the magnesium alloy sheet on clean aluminum foil, finishing, packaging, placing in polyethylene bag, and sealing for storage. In this operation, the finger does not contact the surface to be joined (the end opposite to the side where the through-hole is opened). After one day, 1 was observed with ESCA.

Large amounts of magnesium, calcium, strontium and oxygen were observed, and additionally very small amounts of zinc, aluminum, carbon, silicon were observed. The main components are believed to be oxides of magnesium, calcium and strontium. A single composition or multiple compositions cannot be distinguished in the analytical device used. After one day, the remaining magnesium alloy piece was taken out, and one end having the through-hole was pinched by a hand so as not to cause adhesion of oil and the like, and inserted into an injection mold set at 140 ℃. Injection molding was carried out in exactly the same manner as in example 1 to obtain 20 integrated composites shown in FIG. 2. On the day of molding, the molded article was put into a hot air dryer at 150 ℃ for 1 hour for annealing, and after one day, the molded article was further subjected to a tensile test, and an average shear force was measured to be 7.3 MPa.

[ example 8]

Exactly the same procedure as in example 1 was carried out, using a 0.8mm thick AZ31B magnesium alloy sheet having an average metal crystal grain size of 7 μm or less, and carrying out pretreatment. Then, the mixture was immersed in a 0.25% citric acid aqueous solution prepared in another tank at 40 ℃ for 30 seconds, and washed with water. Then, the steel sheet was immersed in an aqueous solution containing 1% vanadium trichloride and set at 45 ℃ for 2 minutes, and sufficiently washed with water. Drying in hot air drier set at 60 deg.C for 10 min, taking out copper wire from magnesium alloy sheet on clean aluminum foil, finishing, packaging, and sealing in polyethylene bag. In this operation, the finger does not come into contact with the surface to be joined (the end opposite to the side where the through-hole is opened). After one day, 1 was observed with ESCA. Large amounts of vanadium, oxygen, small amounts of magnesium, and additionally very small amounts of zinc, aluminum, silicon were observed. The main component is considered to be vanadium oxide or oxides of vanadium and magnesium.

After one day, the remaining magnesium alloy piece was taken out, and one end having the through-hole was pinched by a hand so as not to cause adhesion of oil or the like, and inserted into an injection mold set at 140 ℃. Injection molding was carried out in exactly the same manner as in example 1 to obtain 20 integrated composites 7 shown in FIG. 2. They were put into a hot air dryer at 150 ℃ for 1 hour for annealing on the day of molding, and further subjected to a tensile test after one day, and an average shear force was measured to be 7.0 MPa. The remaining 10 integrated products were coated with paint "オ - マツク/シルバ - メタリツク (trade name)" in a set thickness of 10 μm, and sintered at 170 ℃ for 30 minutes. The spray was carried out using 5% saline at 35 ℃ for 8 hours, and the spray was washed with water and dried, but no abnormality was observed in appearance.

[ example 9]

Example 9 is an example for confirming the effect of the PPS resin. As the resin to be injected, "サステイ - ル GS-30 (trade name)" which is a PPS resin containing 30% of glass fiber (manufactured by Tokyo, Tosoh, Japan) was used. The injection conditions in molding were such that the injection temperature was 310 ℃ and the mold temperature was 140 ℃. The conditions were exactly the same as those in example 1 except for the injection molding conditions. Tensile breaking tests were conducted on 4 of the molded articles on the day of molding, and the average shear force was 8.8MPa (90 Kgf/cm)²). On the day of molding, 5 pieces were put into a hot air dryer at 170 ℃ and annealed for 1 hour, and after one day, further subjected to a tensile test, and an average shear force was measured to be 9.3 MPa.

The remaining 10 integrated products were coated with paint "オ - マツク/シルバ - メタリツク (trade name)" in a set thickness of 10 μm, and sintered at 170 ℃ for 30 minutes. The coating solution was sprayed with 1% saline at room temperature for 8 hours, washed with water and dried, but no abnormality was observed in appearance.

[ example 10]

Example 10 is an example for confirming the effect of the PPS resin. The magnesium alloy sheet was treated in substantially the same manner as in example 9, and injection bonding was also carried out in substantially the same manner as in example 9. However, the PPS composition (1) obtained in preparation example 1 of a PPS composition was used in place of "サステイ - ル GS-30" used in example 9. Thus, 20 integrated composites 7 shown in FIG. 2 were obtained. The size of the resin part is 10mm × 45mm × 5mm, and the joint surface 6 is 0.5cm of 10mm × 5mm²。

Tensile breaking tests were conducted on 4 of the molded articles on the day of molding, and the average shear force was 13.0 MPa. On the day of molding, they were put into a hot air dryer at 170 ℃ for 5 annealed sheets for 1 hour, and after one day, they were further subjected to a tensile test, and an average shear force was measured to be 12.8 MPa. The remaining 10 integrated products were coated with paint "オ - マツク/シルバ - メタリツク (trade name)" in a set thickness of 10 μm, and sintered at 170 ℃ for 30 minutes. The resultant mixture was washed with water and dried by spraying 5% saline at 35 ℃ for 8 hours, but no abnormality was observed in appearance.

[ example 11]

A composite was obtained in the same manner as in example 10 except that the PPS composition (3) obtained in preparation example 3 was used in place of the PPS composition (1) obtained in preparation example 1 of the PPS composition. Annealing was performed at 170 ℃ for 1 hour on the day of molding, and after two days, the composite was subjected to shear force measurement using a tensile tester, and the average was 12.5 MPa. The remaining 10 integrated products were coated with a coating material "オ - マツク/シルバ - メタリツク (trade name)" (manufactured by osaka, bridge chemical industries, japan) at a set thickness of 10 μm, and sintered at 170 ℃x30 minutes. The spray was carried out using 5% saline at 35 ℃ for 8 hours, and the spray was washed with water and dried, but no abnormality was observed in appearance.

[ example 12]

A magnesium alloy sheet was produced and injection molded in exactly the same manner as in example 10 except that the PPS composition (2) obtained in preparation example 2 was used instead of the PPS composition (1) obtained in preparation example 1, to obtain a composite. The resulting composite was annealed at 170 ℃ for 1 hour. In short, the experiment was conducted using a PPS-based resin composition containing only a very small amount of a polyolefin-based polymer and only a filler. After one day, they were subjected to a tensile test, and as a result, the average of 10 shear forces was 9.0 MPa. The results were not more than about 70% of the values of example 1, showing the difference in the resin materials used.

[ example 13]

A0.8 mm thick AZ31B alloy sheet having an average metal crystal grain size of 7 μm was used. The rectangular pieces were cut in the same manner as in example 1, and immersed in a 10% aqueous solution of a degreasing agent "クリ - ナ - (Cleaner) 160" set at 75 ℃ for 5 minutes, followed by sufficiently water washing. Next, a 2% acetic acid aqueous solution set to 40 ℃ was prepared in another tank, and the alloy piece was immersed in the aqueous solution for 2 minutes and sufficiently washed with water. Black dirt is attached. Subsequently, a 7.5% aqueous solution of a degreasing agent for aluminum alloy "NE-6 (trade name)" set at 75 ℃ was prepared in another tank, and the solution was immersed for 5 minutes and sufficiently washed with water. Subsequently, a 20% sodium hydroxide aqueous solution set at 75 ℃ was prepared in another tank, and a set of the alloy pieces was immersed in the aqueous solution for 5 minutes and sufficiently washed with water. The pretreatment was carried out in the same manner as in example 1.

Subsequently, the mixture was immersed in a 0.5% aqueous solution of citric acid hydrate at 40 ℃ for 15 seconds, which was prepared in another tank, and then washed with water. Then, an aqueous solution containing 3% potassium permanganate, 1% acetic acid, and 0.5% sodium acetate hydrate was prepared, the temperature was set at 45 ℃, and the immersion was carried out for 1 minute, followed by sufficient water washing. The mixture was brown, dried in a hot air dryer set at 60 ℃ for 10 minutes, and copper wire was pulled out from the magnesium alloy sheet on a beautiful aluminum foil, conditioned and packed, and then put in a polyethylene bag and stored in a sealed state. In this operation, the finger does not contact the surface to be joined (the end opposite to the side where the through-hole is opened).

After two days, 1 was observed with ESCA, and a large amount of manganese and oxygen was observed, and a trace amount of magnesium, zinc, aluminum, carbon, and silicon was also observed. The main component is manganese oxide containing manganese dioxide as a main component. The color was also brown, which was demonstrated. After one day, the remaining magnesium alloy piece was taken out, and one end having the through-hole was pinched by a hand so as not to allow oil and the like to adhere thereto, and the magnesium alloy piece was inserted into an injection mold set at 140 ℃. In the same manner as in example 1, 20 integrated composites 7 shown in FIG. 2 were obtained.

On the day of molding, the molded article was put into a hot air dryer at 170 ℃ for 1 hour for annealing, and after one day, the molded article was further subjected to a tensile test, and an average shear force was measured to be 15.1 MPa. The remaining 10 integrated products were coated with a coating "オ - マツク/シルバ - メタリツク (trade name)" at a set thickness of 10 μm and sintered at 170 ℃ for 30 minutes. The spray was carried out using 5% saline at 35 ℃ for 8 hours, and the spray was washed with water and dried, but no abnormality was observed in appearance.

[ example 14]

The procedure of example 13 was exactly the same as that of example 13, and the AZ31B alloy sheet was pretreated. Then, the mixture was immersed in a 0.25% aqueous solution of citric acid hydrate at 40 ℃ for 1 minute, which was prepared in another tank, and washed with water. Then, an aqueous solution containing 2% potassium permanganate, 1% acetic acid, and 0.5% sodium acetate hydrate was prepared, the temperature was set to 45 ℃, and the immersion was performed for 1 minute and water washing was performed. Drying in a hot air drier set at 60 deg.C for 15 min, taking out copper wire from magnesium alloy sheet on clean aluminum foil, packaging, placing in polyethylene bag, and sealing.

After two days, it was taken out, inserted into an injection molding die set at 140 ℃ and the PBT composition (1) was injected. The injection molding conditions were the same as in example 1. The integrated material shown in FIG. 2 was obtained, and was put into a hot air dryer at 150 ℃ for 1 hour on the same day to be annealed, and after one day, the tensile test was further performed, and the average shear force was measured to be 15.8 MPa.

The remaining 10 integrated products were coated with a coating "オ - マツク/シルバ - メタリツク (trade name)" at a set thickness of 10 μm and sintered at 170 ℃ for 30 minutes. The spray was carried out using 5% saline at 35 ℃ for 8 hours, and the spray was washed with water and dried, but no abnormality was observed in appearance.

Comparative example 1

Comparative example 1 is an experiment conducted to confirm the effect of the conversion treatment of example 1. A magnesium alloy sheet 1 was obtained in the same manner as in example 1 except that the conversion treatment was not performed. That is, the AZ31B magnesium alloy sheet 1 was produced, and degreasing, rough etching, desmutting, and fine etching were performed until desmutting was achieved. In short, the manganese phosphate-based non-chromate treatment was not performed, but the washing and drying were performed. After two days, the remaining magnesium alloy sheet 1 was taken out, and one end having the through-hole was pinched by a hand so as not to cause adhesion of oil or the like, and inserted into an injection mold set at 140 ℃.

The injection molding mold was closed, and the same PBT-series resin as in example 1 was injected at an injection temperature of 260 ℃. The mold temperature was 140 ℃ to obtain 14 integrated composites shown in FIG. 2. The size of the resin part is 10mm × 45mm × 5mm, and the joint surface 6 is 0.5cm of 10mm × 5mm². After annealing at 150 ℃ for 1 hour on the day of molding, 4 composites were subjected to a tensile breaking test, and the average shear force was measured to be 7.4 MPa.

Paint "オ - マツク/シルバ - メタリツク (trade name)" was applied to 10 remaining integrated products at a set thickness of 10 μm, and sintered at 170 ℃ for 30 minutes. The next day, the coated article was subjected to brine spraying for 8 hours at room temperature using 1% brine, washed with water, and dried, and as a result, fine coating film swelling was observed in all integrated products. The 10 integrated products were all subjected to a tensile breaking test, and as a result, an average shear force of 4.9MPa (50 kgf/cm)²). A brittle oxide film also penetrated into the fracture surface, and it was confirmed that the coating alone was not used in the conversion treatment.

Comparative example 2

A magnesium alloy sheet was obtained in the same manner as in example 1 except that the conversion treatment was not carried out. That is, an AZ31B magnesium alloy sheet was produced, and degreasing, rough etching, desmutting, and fine etching were performed until desmutting was achieved. In short, the manganese phosphate-based non-chromate treatment was not performed, but the washing and drying were performed. No crystalline body was observed by electron microscope observation, and the surface was a natural oxide layer of magnesium alloy.

The remaining magnesium alloy piece was taken out two days later, and one end having the through-hole was pinched by a hand so as not to cause adhesion of oil or the like, and inserted into an injection molding die set at 140 ℃. The metal mold was closed, and PPS (1) obtained in preparation example 1 was injected at an injection temperature of 310 ℃. The mold temperature was 140 ℃ to obtain 14 integrated composites shown in FIG. 2. The size of the resin part is 10mm × 45mm × 5mm, and the joint surface 6 is 0.5cm of 10mm × 5mm². Tensile breaking tests were carried out on 4 composites on the day of formation, and the average shear force was measured to be 11.3 MPa.

Paint "オ - マツク/シルバ - メタリツク (trade name)" was applied to 10 remaining integrated products at a set thickness of 10 μm, and sintered at 170 ℃ for 30 minutes. The next day, the coated article was subjected to brine spraying using 5% brine at 35 ℃ for 8 hours, washed with water, and dried, and as a result, fine coating film swelling was observed in all integrated products. Tensile breaking tests were carried out on all of the 10 integrated products, and the average shear force was measured to be 7.0 MPa. A brittle oxide film also penetrated into the fracture surface, and it was confirmed that the coating alone was not used in the conversion treatment.

Comparative example 3

Production of a composite was attempted in the same manner as in example 10 except that the PPS composition (4) of preparation example 4 of the PPS composition was used in place of the PPS composition (1) of preparation example 1 of the PPS composition. In short, the experiment was conducted using a PPS resin composition containing a polyolefin-based polymer in a very large amount. This resin material should be called a polyolefin-based material, as compared with a PPS-based material. A large amount of gas is generated during molding, and the operation is stopped due to difficulty in injection molding.

Comparative example 4

A0.8 mm thick AZ31B magnesium alloy (manufactured by Nippon Metal industries, Tokyo, Japan) having a final surface processed to a wet finish and an average metal crystal grain size of 7 μm was used. The copper wire was cut into 18mm × 45mm pieces, through holes were formed in the ends of the pieces, and the copper wire coated with vinylidene chloride was passed through the through holes, and the copper wire was bent so that the magnesium alloy pieces did not overlap each other, and 10 magnesium alloy pieces were hung simultaneously.

A commercially available degreasing agent for magnesium alloy "クリ - ナ - (Cleaner) 160" was put into hot water set at 65 ℃ at a concentration of 10% in a degreasing bath and dissolved therein. The alloy sheet was immersed in the solution for 5 minutes, sufficiently washed with water, and dried at 67 ℃ for 15 minutes. In short, the test was conducted to confirm the bonding strength of the alloy subjected to only the degreasing treatment. After 3 days, 1 of them was photographed with an electron microscope. The photograph is shown in FIG. 6. After one more day, the alloy sheet was inserted into an injection molding die set at 140 ℃, and the PPS composition (1) was injected thereinto. The injection molding conditions were the same as those in example 10, and it was found that the injection molding was not integrated when the injection mold was opened.

Comparative example 5

An experiment exactly the same as in comparative example 4 was conducted except that the resin used was replaced with the PPS composition (1) and the PBT composition (1) was used, and the injection molding conditions were made to match those in example 1. At this time, the resin molded article and the magnesium alloy sheet cannot be integrated with each other when the injection mold is opened.

The following table is a list showing the summary of the above examples and comparative examples.

[ Table 1]

Examples and comparative examples

	Base material	Conversion treatment liquid	Resin (Main)	Strength (Mpa)	Remarks for note
						Example 1	AZ31B	Manganese phosphates	PBT	11.9
Example 2	AZ31B	Potassium permanganate	PBT	11.6	The surface is a ball
						Example 3	AZ31B	Zirconium acetylacetonate and titanium fluoride	PBT	7.7
Example 4	AZ31B	Zinc acetylacetonate, titanium sulfate	PBT	6.9
						Example 5	AZ31B	Chromic acid	PBT	6.6
Example 6	AZ31B	Potassium carbonate	PBT	7.0
						Example 7	AZ31B	Hydrated calcium nitrate, hydrated strontium nitrate	PBT	7.3
Example 8	AZ31B	Vanadium trichloride	PBT	7.0
						Example 9	AZ31B	Manganese phosphates	PPS	9.3	Can be used for salt water test
Example 10	AZ31B	Manganese phosphates	PPS, olefins	12.8
						Example 11	AZ31B	Manganese phosphates	PPS, olefins	12.5
Example 12	AZ31B	Manganese phosphates	PPS	9.0	Adding small amount of polyolefin
						Example 13	AZ31B	Potassium permanganate	PBT	15.1

Example 14	AZ31B	Potassium permanganate	PBT PET	15.8
						Comparative example 1	AZ31B	Only etching and desmutting treatment	PBT	7.4	No salt water test was performed
Comparative example 2	AZ31B	Only etching and desmutting treatment	PPS	11.3	No salt water test was performed
						Comparative example 3	AZ31B	Manganese phosphates	PPS, olefins	Cannot be shaped	Adding a large amount of polyolefins
Comparative example 4	AZ31B	Degreasing only	PPS, olefins	Is not fixed
						Comparative example 5	AZ31B	Degreasing only	PBT PET	Is not fixed

The metal-resin composite and the method for producing the same according to the present invention can be used for housings of electronic devices, housings of home electric appliances, structural parts, mechanical parts, and the like. In particular, magnesium alloys have higher strength and bending modulus per weight than aluminum alloys and steel, and thus are widely used as structural materials and parts. In order to effectively utilize such characteristics, it is expected to be applied to mobile electronic devices, airframe parts of aircrafts, automobile parts, and the like, which require weight reduction.

Claims (3)

1. A method for producing a composite of a metal and a resin, comprising:

a shaping step of shaping a casting or an intermediate material made of a magnesium alloy into a shaped part by machining;

a conversion treatment step of forming 1 type selected from the group consisting of metal oxides, metal carbonates, and metal phosphates on the surface layer of the shaped part;

an injection step of inserting the shaped part having completed the liquid treatment step into an injection molding die and injecting a molten resin composition containing polybutylene terephthalate or polyphenylene sulfide as a main component;

and a fixing step of fixing the shaped part and the resin composition integrally by the injection molding and curing the molded part by penetrating into a recess of the metal oxide or the metal phosphate.

2. The method of producing a metal-resin composite according to claim 1,

when observed by an electron microscope, at least 2 plate-like crystals were observed per square area of 1 μm square on the surface layer.

3. The method of producing a metal-resin composite according to claim 1,

the surface layer was covered with a cake of needle-like crystals wound thereon as observed by an electron microscope.