CN109207814A - With the 5 line aluminium alloy Strips and its manufacturing method of good gloss degree after anodic oxidation - Google Patents

Abstract

The invention discloses 5 line aluminium alloy Strips and its manufacturing method with good gloss degree after a kind of high-intensitive and anodic oxidation.The sum of weight percent is 100%, and each chemical component and its shared weight percent are Si≤0.04%, Fe≤0.05% in the aluminum alloy sheets and strips, Cu≤0.05%, Mn 0.4-0.5%, Mg 3.0 ~ 3.5%, Ti 0.005-0.012%, surplus are Al and inevitable impurity；And Fe/Si≤1.5；It is by aluminium ingot, aluminium intermediate alloy ingot, magnesium ingot is smelting, is cast as big plate ingot, then sawing is carried out to ingot casting, behind milling face, heated, hot rolling, cold rolling and etc. be made.Gained aluminum alloy sheets and strips tensile strength with higher and yield strength, and there is very high glossiness after anodic oxidation.

Description

5 line aluminium alloy Strips and its manufacture after anodic oxidation with good gloss degree Method

Technical field

The invention belongs to aluminium and aluminium alloy preparation fields, and in particular to have good light after a kind of high-intensitive and anodic oxidation The manufacturing method of 5 line aluminium alloy Strips of damp degree.

Background technique

Since 2018, electronics industry constantly promotes the replacement of wireless network to upgrade, and the 5G high speed epoch are ready to appear, herein Under background, electronic equipment full metal jacket designs the demand of network transmission of having been unable to meet, therefore a domestic line product such as Huawei, millet Participants in a bridge game's machine falls over each other to issue the double-sided glass design mobile phone of 4.5G network.Occur in order to protect glass, when avoiding falling broken, it is desirable that The surface hardness of mobile phone frame must be in HV90 or more；While in order to improve the overall aesthetic degree of fuselage, designer wishes frame Material has the glazed high gloss effect of class.Similarly, notes this product urgently needs also in the development trend for clinging to 5G on one's trail It wants the aluminium of high intensity to carry out punching design to part when its design, guarantees transmission speed, avoid in its market by plate Computer and mobile phone are further seized.

Currently, the electronic product frame material of high-intensitive high gloss mainly uses stainless steel material, through a large amount of CNC and It is made after sanding and polishing, but the technique production procedure is long, processing cost is high.Under high-intensitive demand, a large amount of aluminium suppliers Develop the alloy product of 5 systems, 6 systems and 7 systems, but it is most of only pay attention to the presentation quality after anode, i.e., whether there is or not " material lines " to lack It falls into, and having ignored after electronic product casing also requires aluminum used anodic oxidation has higher glossiness.

At present on automotive trim strip, part 6 is that alloy extrusion material can realize high gloss (such as patent CN after anode 105838942A), but product strength is low, 5 be alloy also have portioned product can produce meet oxidation film polishing after have mirror surface effect Fruit (such as patent CN 107190184B), but intensity is insufficient, and since Mg content is high, in order to avoid β phase burning, uniform heating process is multiple It is miscellaneous, increase cost and influences production efficiency.

Summary of the invention

The purpose of the present invention is to provide the 5 line aluminium alloy plates with good gloss degree after a kind of high-intensitive and anodic oxidation The manufacturing method of band.

To achieve the above object, the present invention adopts the following technical scheme:

With 5 line aluminium alloy Strips of good gloss degree after a kind of high-intensitive and anodic oxidation, the sum of weight percent is 100%, each chemical component and its shared weight percent in the aluminum alloy sheets and strips are as follows: Si≤0.04%, Fe≤0.05%, Cu≤ 0.05%, Mn 0.4-0.5%, Mg 3.0 ~ 3.5%, Ti 0.005-0.012%, surplus are Al and inevitable impurity；And Fe/ Si≤1.5。

The preparation method of the 5 line aluminium alloy Strip the following steps are included:

1) aluminium ingot, aluminium intermediate alloy ingot, magnesium ingot are distinguished and carries out ingredient after smelting furnace melts, then casting is made through semi-continuous casting Ingot；

2) gained ingot casting is sent into behind sawing, milling face heating furnace, is warming up to 500 ~ 530 DEG C after 430 ~ 460 DEG C of 3 ~ 6h of heat preservation, 4 ~ 20h, hot rolling of then coming out of the stove are kept the temperature, hot rolling finishing temperature is 250 ~ 350 DEG C, hot rolled thickness 2.0-7.0mm；

3) by the coiled material after hot rolling after the cold rolling of 20-90%, direct annealed finished product；Or it is cold-rolled to thick middle After degree, 2-6h is kept the temperature under 300 ~ 360 DEG C of intermediate anneal temperatures, then be cold rolled to finished product thickness, then pass through 120-280 DEG C, 2- After the finished products of 6h, stretch-bending straightening finished product.

After stretch-bending straightening, tensile strength >=280MPa of gained aluminum alloy sheets and strips, yield strength >=240MPa extend Rate >=6% meets the demand that cracking does not occur for corner after pressing and bending deforms；At anode oxidation process through 15 ~ 20 μm of film thickness After reason, value >=120 glossiness GU at 60 ° of measurement angles.

Inventor it has been investigated that, whether the film layer after aluminum alloy sheets and strips anode has high glossiness, with anodic oxygen β phase (AL in chemical corrosion process and anodic oxidation energization film forming procedure before change₂Mg₃) corrosion spalling situation it is related: β phase Rotten candle current potential be -1.24V, be anode for matrix α (Al), thus it is preferential rotten candle occurs, if β phase be distributed it is tiny Even, the structure of oxidation film will be than more complete, and glossiness is high；If β phase intercrystalline precipitation is simultaneously assembled, chemistry and the lower crystal boundary of the corrosion that is powered The pit for having apparent depth, influences the integrality of oxidation film, and then has caused degree insufficient.

And during being distributed to β phase and the influence factor of quantity is analyzed, inventors have found that suitably reducing Mg's Content, it will help reduce the precipitation of β phase, but reduce too much, final intensity will be insufficient；And adding Zn facilitates the opposite τ of β Phase (Al₂Mg₃Zn₃) change, the quantity of β phase is reduced, but waste material is difficult to handle utilization after addition Zn；It is properly added Mn not only Intensity is helped to improve, additionally aids β phase homogeneous precipitation in Casting Ingot Solidification Process, and then have thin in the segregation of crystal boundary by it Change the effect of tissue；In addition, low Fe/Si ratio can make superfluous Si and Mg form Mg₂Si, to be further reduced accumulation shape β phase quantity.

Meanwhile in terms of the uniform heating process of ingot casting, due to β (AL₂Mg₃) mutually belonging to low melting point phase, the heating more than 460 DEG C will It will appear burning and influence going on smoothly for course of hot rolling.

On this basis, the present invention is necessary by adding in the 5 line aluminium alloy strips containing Mg content 3.0 ~ 3.5% Mn, and control Fe/Si ratio is realized while promoting alloy strength, improves the quantity and distribution of perishable β phase, and is passed through pair Casting, hot rolling heating cycle and cold rolling processing technology are improved, with realize the type to compound, size and number it is effective Control, the excellent quality of high gloss is horizontal after so that 5 line aluminium alloy products of gained is had both high-intensitive and anodic oxidation, this is general 5 be not available for alloy (corrosion condition is shown in Fig. 1, and remaining etch pit is smaller more uniform, anode rear surface oxidation film it is complete Whole property will be better, and glossiness is also higher).Wherein, the combination of well-designed and technique based on ingredient makes in ingot casting slightly raw β phase is tiny and is evenly distributed, and 3 ~ 6h is kept the temperature at 430 ~ 460 DEG C can be realized whole back dissolvings, compares other high Mg alloy cast ingots Soaking time it is short, therefore production efficiency can be effectively improved while improving product quality.

In short, gained aluminum alloy sheets and strips tensile strength with higher and yield strength, and having after anodic oxidation There is very high glossiness, when can effectively solve appearance member of traditional 5 line aluminium alloys as electronic products such as mobile phone, pen electricity, cameras, Yield strength is insufficient, and complete machine, which falls easy to damage or surface metallic luster deficiency after sandblasting and anodic oxidation, influences beautiful ask Topic.

Detailed description of the invention

Fig. 1 is 5 line aluminium alloy (a) prepared by the present invention and microstructure of general 5 line aluminium alloy (b) after phosphoric acid corrosion It compares (after being corroded β using phosphoric acid, the evidence of corrosion under microstructure is the distribution situation of β phase).

Specific embodiment

With 5 line aluminium alloy Strips of good gloss degree after a kind of high-intensitive and anodic oxidation, weight percent it Be 100%, weight percent shared by each chemical component in the aluminum alloy sheets and strips are as follows: Si≤0.04%, Fe≤0.05%, Cu≤ 0.05%, Mn 0.4-0.5%, Mg 3.0 ~ 3.5%, Ti 0.005-0.012%, surplus are Al and inevitable impurity；And Fe/ Si≤1.5。

The preparation method of the 5 line aluminium alloy Strip the following steps are included:

1) aluminium ingot, aluminium intermediate alloy ingot, magnesium ingot are distinguished and carries out ingredient after smelting furnace melts, then casting is made through semi-continuous casting Ingot；

2) gained ingot casting is sent into behind sawing, milling face heating furnace, is warming up to 500 ~ 530 DEG C after 430 ~ 460 DEG C of 3 ~ 6h of heat preservation, 4 ~ 20h, hot rolling of then coming out of the stove are kept the temperature, hot rolling finishing temperature is 250 ~ 350 DEG C, hot rolled thickness 2.0-7.0mm；

3) by the coiled material after hot rolling after the cold rolling of 20-90%, direct annealed finished product；Or it is cold-rolled to thick middle After degree, 2-6h is kept the temperature under 300 ~ 360 DEG C of intermediate anneal temperatures, then be cold rolled to finished product thickness, then pass through 120-280 DEG C, 2- After the finished products of 6h, stretch-bending straightening finished product.

The reasons why carrying out numerical definiteness to the content of each ingredient below is illustrated:

Mg: the Mg in alloy is addition element necessary to for guaranteeing sheet alloy intensity, if content is lower than 3.0%, finished product Yield strength index will not be able to satisfy, if content is more than 3.5%, the β phase of formation significantly increases, the trend enhancing assembled to crystal boundary, Complete anodic oxidation membrane structure will be obtained after being unfavorable for anodic oxidation；

Fe:Fe is the impurity element being difficult to avoid that in alloy, but when Fe content is more than 0.05%, will form β (AlFeSi) phase, into One step, which increases, even promotes AL₆Fe phase increases, and rich Fe phase is non-breakable in subsequent homogenization and rolling deformation process, and Because aluminum substrate is preferentially corroded when anodic oxidation, coarse rich Fe, which meets, to be peeled off and forms big hole in oxidation film, seriously The glossiness of oxidation film is influenced, it is preferably more lower better.

Si: the Si in alloy is mainly impurity, keeps suitable ratio with Fe, on the one hand can avoid the Fe for being difficult to remove to Coarse AL₆On the other hand Fe phase transition can also attract part Mg to form Mg₂Si allows Mg to play dispersion-strengthened action in the alloy And avoid the aggregation of β phase, more than 0.04% after elongation percentage it is impacted, and AL-Fe-Si phase easy to form influences the bright property of oxidation film.

Ti:Ti is the essential element for inhibiting cast sturcture's roughening, and preferred content 0.08% will form thick when content is higher Large compound promotes forming region heterochromatic.

Mn:Mn is conducive to improve the intensity of material, and addition in a certain range can be dissolved into AlFe phase, improve Fe's Adverse effect, and can significantly promote β phase (AL in ingot solidification₂Mg₃) homogeneous precipitation, improve coating mass；And it adds super When crossing 0.5% or more, AlFeMnSi compound will be formed, oxidation film is made to become muddy and no longer thoroughly white.

In order to make content of the present invention easily facilitate understanding, With reference to embodiment to of the present invention Technical solution is described further, but the present invention is not limited only to this.

Example example 1

With 5 line aluminium alloy Strips of good gloss degree after a kind of high-intensitive and anodic oxidation, the sum of weight percent is 100%, contained chemical component are as follows: Si0.04%, Fe0.05%, Cu 0.001%, Mn 0.4%, Mg 3.5%, Ti 0.005%, it is remaining Amount is Al and inevitable impurity；And Fe/Si=1.25.

The preparation method of the 5 line aluminium alloy Strip the following steps are included:

1) semi-continuous casting is carried out after aluminium ingot, aluminium intermediate alloy ingot, magnesium ingot being distinguished smelting furnace thawing, ingredient, obtains ingot casting；

2) gained ingot casting is sent into behind sawing, milling face heating furnace, is warming up to 500 DEG C after 6h is kept the temperature at 430 DEG C, keeps the temperature 4h, so After come out of the stove hot rolling, hot rolling finishing temperature is 250 DEG C, hot rolled thickness 7.0mm；

3) coiled material after hot rolling is produced by following cold-rolling process: 7.0-3.6-2.4-1.6-1.2- moderate heat -0.8- finished products.Its Intermediate annealing process is that 2h is kept the temperature at 360 DEG C, and finished product annealing process is to keep the temperature 4h at 120 DEG C.

The tensile strength of the aluminium alloy strips of obtained 0.8mm thickness is 310MPa, yield strength 257MPa, elongation percentage 8.7%, after the anode oxidation process anode of 15 ~ 20 μm of film thickness, value=145 surface gloss GU at 60 ° of measurement angles.

Embodiment 2

With 5 line aluminium alloy Strips of good gloss degree after a kind of high-intensitive and anodic oxidation, the sum of weight percent is 100%, contained chemical component are as follows: Si0.03%, Fe0.034%, Cu 0.02%, Mn 0.5%, Mg 3.3%, Ti 0.012%, it is remaining Amount is Al and inevitable impurity；And Fe/Si=1.13.

The preparation method of the 5 line aluminium alloy Strip the following steps are included:

1) semi-continuous casting is carried out after aluminium ingot, aluminium intermediate alloy ingot, magnesium ingot being distinguished smelting furnace thawing, ingredient, obtains ingot casting；

2) gained ingot casting is sent into behind sawing, milling face heating furnace, is warming up to 520 DEG C after 4h is kept the temperature at 460 DEG C, keeps the temperature 20h, so After come out of the stove hot rolling, hot rolling finishing temperature is 300 DEG C, hot rolled thickness 5.0mm；

3) coiled material after hot rolling is produced by following cold-rolling process: 5.0-3.0-2.0- moderate heat -1.6-1.0- finished products.Among it Annealing process is that 6h is kept the temperature at 300 DEG C, and finished product annealing process is to keep the temperature 2h at 280 DEG C.

The tensile strength of the aluminium alloy strips of obtained 1.0mm thickness is 303MPa, yield strength 260MPa, elongation percentage 9.6%, after the anode oxidation process anode of 15 ~ 20 μm of film thickness, value=137 surface gloss degree GU at 60 ° of measurement angles.

Embodiment 3

With 5 line aluminium alloy Strips of good gloss degree after a kind of high-intensitive and anodic oxidation, the sum of weight percent is 100%, contained chemical component are as follows: Si0.024%, Fe0.036%, Cu 0.05%, Mn 0.43%, Mg 3.5%, Ti 0.010%, Surplus is Al and inevitable impurity；And Fe/Si=1.5.

The preparation method of the 5 line aluminium alloy Strip the following steps are included:

1) semi-continuous casting is carried out after aluminium ingot, aluminium intermediate alloy ingot, magnesium ingot being distinguished smelting furnace thawing, ingredient, obtains ingot casting；

2) gained ingot casting is sent into behind sawing, milling face heating furnace, is warming up to 530 DEG C after 3h is kept the temperature at 440 DEG C, keeps the temperature 6h, so After come out of the stove hot rolling, hot rolling finishing temperature is 350 DEG C, hot rolled thickness 3.0mm；

3) the coiled material direct cold rolling after hot rolling is to finished product thickness, cold-rolling process are as follows: 3.0-2.0-1.6- finished products.

The tensile strength of the aluminium alloy strips of obtained 1.6mm thickness is 290MPa, yield strength 246MPa, elongation percentage 10.8%, after the anode oxidation process anode of 15 ~ 20 μm of film thickness, value=130 surface gloss GU at 60 ° of measurement angles.

Comparison example 1

Existing 5 be alloy A, and the sum of weight percent is 100%, chemical composition content are as follows: Si 0.12%, Fe 0.24%, Cu 0.05%, Mn 0.43%, Mg 4.7%, Zn 0.3%, Ti 0.012%, surplus are Al and inevitable impurity；Fe/Si=2.0.

Preparation method includes the following steps:

1) semi-continuous casting is carried out after aluminium ingot, aluminium intermediate alloy ingot, magnesium ingot being distinguished smelting furnace thawing, ingredient, obtains ingot casting；

2) gained ingot casting is sent into heating furnace behind sawing, milling face, hot rolling of coming out of the stove after heat preservation 3h at 480 DEG C, hot rolling finishing temperature It is 350 DEG C, hot rolled thickness 4.0mm；

3) the coiled material direct cold rolling after hot rolling is to finished product thickness, cold-rolling process are as follows: 4.0-2.0-1.6- finished products.

The tensile strength of the aluminium alloy strips of obtained 1.6mm thickness is 290MPa, yield strength 250MPa, elongation percentage 11.2%, after the anode oxidation process anode of 15 ~ 20 μm of film thickness, value=106 surface gloss GU at 60 ° of measurement angles.

Comparison example 2

Existing 5 be alloy B, and the sum of weight percent is 100%, chemical composition content are as follows: Si 0.03%, Fe 0.06%, Cu 0.03%, Mn 0.13%, Mg 2.8%, Cr 0.1%, Ti 0.012%, surplus are Al and inevitable impurity；Fe/Si=2.0.

Preparation method includes the following steps:

1) semi-continuous casting is carried out after aluminium ingot, aluminium intermediate alloy ingot, magnesium ingot being distinguished smelting furnace thawing, ingredient, obtains ingot casting；

2) gained ingot casting is sent into heating furnace behind sawing, milling face, hot rolling of coming out of the stove after heat preservation 6h at 480 DEG C, hot rolling finishing temperature It is 320 DEG C, hot rolled thickness 2.5mm；

3) the coiled material direct cold rolling after hot rolling is to finished product thickness, cold-rolling process are as follows: 2.5-1.6- moderate heat -1.0- finished products.

The tensile strength of the aluminium alloy strips of obtained 1.0mm thickness is 300MPa, yield strength 252MPa, elongation percentage 9.2%, after the anode oxidation process anode of 15 ~ 20 μm of film thickness, value=114 surface gloss GU at 60 ° of measurement angles.

The foregoing is merely presently preferred embodiments of the present invention, all equivalent changes done according to scope of the present invention patent with Modification, is all covered by the present invention.

Claims (2)

1. the 5 line aluminium alloy Strips with good gloss degree after a kind of high-intensitive and anodic oxidation, it is characterised in that: by weight Measuring the sum of percentage is 100%, each chemical component and its shared weight percent in aluminum alloy sheets and strips are as follows: Si≤0.04%, Fe ≤ 0.05%, Cu≤0.05%, Mn 0.4-0.5%, Mg 3.0 ~ 3.5%, Ti 0.005-0.012%, surplus is for Al and unavoidably Impurity；And Fe/Si≤1.5.

2. a kind of method for manufacturing 5 line aluminium alloy Strip as described in claim 1, it is characterised in that: the following steps are included:

1) aluminium ingot, aluminium intermediate alloy ingot, magnesium ingot are distinguished and carries out ingredient after smelting furnace melts, then casting is made through semi-continuous casting Ingot；

2) gained ingot casting is sent into behind sawing, milling face heating furnace, is warming up to 500 ~ 530 DEG C after 430 ~ 460 DEG C of 3 ~ 6h of heat preservation, 4 ~ 20h, hot rolling of then coming out of the stove are kept the temperature, hot rolling finishing temperature is 250 ~ 350 DEG C, hot rolled thickness 2.0-7.0mm；

3) by the coiled material after hot rolling after the cold rolling of 20-90%, direct annealed finished product；Or it is cold-rolled to thick middle After degree, 2-6h is kept the temperature under 300 ~ 360 DEG C of intermediate anneal temperatures, then be cold rolled to finished product thickness, then pass through 120-280 DEG C, 2- After the finished products of 6h, stretch-bending straightening finished product.