JP2013014471A - Translucent ceramics joint, and method for manufacturing the same - Google Patents

Abstract

An object of the present invention is to provide a bonded body of ceramics and ceramics and a method for manufacturing the same. Furthermore, the present invention provides a joined body of ceramics and translucent ceramics, particularly a joined body of a colored zirconia sintered body and translucent ceramics, and a method for producing the same.
A sintered ceramic body in which a colored zirconia sintered body is bonded to a translucent ceramic without a bonding material. By firing the translucent ceramic 2 and the colored zirconia sintered body 1, the colored zirconia sintered body 1 is contracted to join the translucent ceramic 2 and the colored zirconia sintered body.
[Selection] Figure 2

Description

  The present invention relates to a joined body made of ceramics and translucent ceramics and a method for producing the same. Furthermore, it is related with the joining method of ceramics and translucent ceramics.

  Ceramics are widely used in industrial member applications because of their excellent heat resistance, wear resistance, and corrosion resistance. In addition, applications of translucent ceramics are expanding due to high aesthetics and texture. For example, as applications of translucent ceramics, applications such as electronic device members such as mobile phones, watch members, and jewelry are being studied. With the expansion of such applications, there is a demand for ceramic members made of ceramics different from translucent ceramics as members having not only higher aesthetics but also higher designability.

  On the other hand, ceramics is a material having high toughness, and it is difficult to process into a complicated shape. Therefore, when producing a ceramic member having a complicated shape, it is necessary to join the translucent ceramic and the ceramic.

  So far, joined bodies of ceramics and ceramics have been studied. For example, a method in which a metal phase is formed on a ceramic surface and bonded as a bonding material, a ceramic bonded body obtained by a so-called metallization method (Patent Document 3), or a bonding material such as ceramic powder or an organic substance is used. The obtained ceramic joined body has been reported (Patent Document 2).

  In addition, a method in which the green compacts before sintering are brought into close contact with each other, a ceramic joined body obtained by so-called co-sintering (Patent Document 1), or a ceramic raw material powder is pressed with a graphite compact during hot pressing. A graphite-ceramic bonded body obtained by performing molding and sintering simultaneously (Non-patent Document 1). Furthermore, a ceramic joined body obtained using a low melting point material has been reported (Patent Document 4).

JP 2003-128473 A Japanese Patent Laid-Open No. 11-92245 JP 2008-169889 A JP 2000-226272 A

Journal of Ceramic Industry Association, Vol. 81, No. 1, p. 46 (1973)

  In a metallization method or a bonding method using a bonding material, a metal phase or a bonding material remains on the bonding surface between ceramics and ceramics. Thereby, the ceramic joined body has low aesthetics. In the ceramic joined body using the translucent ceramic, the aesthetics are particularly low.

  Furthermore, the bonding strength of the ceramic bonded body is affected by the strength of the third component such as a bonding material. Therefore, the strength of the ceramic joined body obtained by joining using a metallizing method or a joining material was significantly lower than that of each joined ceramic.

  In the molding and sintering of the ceramic raw material powder and the co-sintering of the molded body, the shape of the finally obtained ceramic joined body is significantly different from the shape before sintering. Therefore, it has been difficult to obtain a ceramic joined body having a desired shape by these methods.

  Ceramic joined bodies using low melting point materials are limited to ceramics in a special composition. Therefore, such a method could not be applied to a colored zirconia sintered body or the like used in a jewelry member or the like.

  Further, these conventional ceramic joined bodies are joined bodies in which one ceramic and the other ceramic are joined to each other on one surface, for example, joined in a laminated form, and have a simple joined state. It was a joined body. Therefore, a ceramic bonded body having a complicated shape such as a shape in which a part or all of the ceramic is bonded so as to be surrounded by other ceramics, for example, a frame shape, an edge shape or the like has not been obtained.

  The present invention solves these problems and provides a bonded body of ceramics and ceramics and a method for manufacturing the same. Furthermore, the present invention provides a joined body of ceramics and translucent ceramics, particularly a joined body of a colored zirconia sintered body and translucent ceramics, and a method for manufacturing the same.

  In view of the above-mentioned problems, the present investigators have studied diligently. As a result, it has been found that a ceramic zygote having a colored zirconia sintered body as a ceramic and a translucent ceramic becomes a ceramic joint having a complicated shape without impairing aesthetics. Furthermore, it discovered that such a ceramic joined body was obtained by utilizing the sintering shrinkage of a sintered compact.

  That is, the present invention is a ceramic joined body composed of a colored zirconia sintered body and a translucent ceramic.

  Hereinafter, the translucent ceramic joined body of the present invention will be described in detail.

  The ceramic joined body of the present invention is a ceramic-ceramic joined body composed of a colored zirconia sintered body and a translucent ceramic. Therefore, the ceramic joined body of the present invention is different from a metal-ceramic joined body made of metal and ceramics, a carbon-ceramic joined body made of carbon and ceramics, etc. (hereinafter referred to as “ceramics-ceramic joined body”. A joined body)). Furthermore, the ceramic joined body of the present invention is also different from a ceramic member in which a sintered zirconia sintered body and a translucent ceramic are integrated after processing each sintered body.

  The ceramic joined body of the present invention comprises a colored zirconia sintered body and a translucent ceramic. The colored zirconia sintered body has particularly high aesthetics. In addition, the translucent ceramic has not only high aesthetics, but also has an optical function as a translucent member or a transparent member due to its transparency. By joining the colored zirconia sintered body and the translucent ceramic, the translucent ceramic joined body of the present invention becomes a ceramic material and a ceramic member excellent not only in aesthetics but also in function.

  The ceramic joined body of the present invention is preferably formed by joining a colored zirconia sintered body and a translucent ceramic. Furthermore, it is more preferable that the colored zirconia sintered body and the translucent ceramic are joined without using a joining material. By bonding without using a bonding material or the like, the colored zirconia sintered body and the translucent ceramic are directly bonded. Thereby, a ceramic joined body turns into a ceramic joined body which does not have a joining layer derived from a joining material in an interface. Therefore, the ceramic joined body of the present invention not only has high aesthetics but also tends to have high strength. Furthermore, in the case of a ceramic joined body composed of a colored zirconia sintered body and a translucent ceramic having a particularly high transparency, the aesthetic properties are particularly likely to be increased by joining them without using a joining material.

  The colored zirconia sintered body and the translucent ceramic do not need to be joined at all the interfaces between them, and only need to be partly joined.

  Here, the bonding material is also called an adhesive or a bonding material. Examples of such a bonding material include inorganic materials such as cement, polymer materials such as organic adhesives, and organic materials.

  The bonded state of the ceramic bonded body can be observed by scanning electron microscope (SEM) observation or the like. For example, in the case of a ceramic joined body joined through a joining material, particles or layers other than these sintered particles are confirmed near the interface between the colored zirconia sintered body and the translucent ceramic. On the other hand, in the case of the ceramic joined body joined without using the joining material, it can be confirmed that the sintered particles of the colored zirconia sintered body and the translucent ceramic are in direct contact.

  Furthermore, in the ceramic joined body of the present invention, the colored zirconia sintered body is preferably joined to the outer periphery of the translucent ceramic, and the colored zirconia sintered body is joined to the translucent ceramic in a frame shape. Is more preferable.

  The colored zirconia sintered body may be bonded to a part of the translucent ceramic. Further, the colored zirconia sintered body may be joined so as to surround the entire outer periphery of the translucent ceramic.

  The shape of the ceramic joined body of the present invention is not particularly limited as long as the colored zirconia sintered body is joined to the translucent ceramic. For example, examples of the translucent ceramic contained in the ceramic joined body of the present invention include plate shapes such as a circular shape, an elliptical shape, a rectangular shape, and a square shape. As an example of the shape of the ceramic joined body of the present invention in which such a translucent ceramic and a colored zirconia sintered body are joined, the shape as shown in FIG. 1 can be exemplified.

  In the present invention, the translucent ceramic is a ceramic having a linear transmittance of greater than 0%, a ceramic having a sample thickness of 1 mm and a linear transmittance in a D65 light source (hereinafter simply referred to as “linear transmittance”) of at least 10%. More preferably, the ceramic is a ceramic having a linear transmittance of at least 25%, and more preferably a ceramic having a linear transmittance of at least 30%. By using such translucent ceramics, aesthetics are enhanced. Thereby, the ceramic joined body of this invention becomes a thing suitable for jewelry and a decoration use.

Furthermore, the translucent ceramic preferably has a linear transmittance of at least 50%, more preferably at least 60%, and even more preferably at least 70%. When the linear transmittance is at least 50%, a ceramic having transparency equivalent to that of the transparent ceramic is obtained. Thereby, since aesthetics become high, it can be used not only for jewelry and ornaments but also for applications such as watch cover materials and display members for electronic devices.
The linear transmittance is a value that can be obtained from the following equation.

Ti = Tt−Td
Tt: Total light transmittance (%)
Td: diffuse transmittance (%)
Ti: Linear transmittance (%)

  The D65 light source is one of light source standards that can be used as a substitute for a standard light source defined by the International Commission on International Illumination (CIE). This light source is light equivalent to natural daylight. The linear transmittance measured with this light source is almost the same value as the transmittance when measured at a measurement wavelength of 550 nm.

As translucent ceramics, yttria (yttrium oxide, Y ₂ O ₃ ) sintered body, spinel (MgAl ₂ O ₄ ) sintered body, yttria-alumina-garnet (YAG; Y ₃ Al ₅ O ₁₂ ) sintered body, A polycrystalline body such as a translucent alumina sintered body or a translucent zirconia sintered body can be exemplified. The translucent ceramic is preferably a translucent ceramic having a gloss comparable to that of the colored zirconia sintered body, and more preferably a translucent zirconia sintered body.

  The translucent zirconia sintered body is preferably a zirconia sintered body containing a cubic fluorite structure in its crystal structure, and more preferably the crystal structure is a single phase of the cubic fluorite structure. preferable.

Examples of the translucent zirconia sintered body include yttria-containing zirconia sintered body, titania (titanium oxide, TiO ₂ ), and yttria-containing zirconia sintered body.

  The amount of yttria contained in the translucent zirconia sintered body is preferably 6 mol% or more and 15 mol% or less, and more preferably 7 mol% or more and 12 mol% or less with respect to the zirconia in the translucent zirconia sintered body. Preferably, it is 8 mol% or more and 10 mol% or less.

  When the translucent zirconia sintered body contains titania, the amount of titania is preferably 3 mol% or more and 20 mol% or less with respect to the total of zirconia and yttria in the translucent zirconia sintered body, and is preferably 5 mol% or more. More preferably, it is 15 mol% or less, and further preferably 8 mol% or more and 12 mol% or less. By containing titania in this range, the transparency of the translucent zirconia sintered body is likely to be high. Furthermore, when the translucent zirconia sintered body contains titania, the average crystal grain size becomes small, and the mechanical strength, particularly the bending strength, tends to increase.

  In the ceramic joined body of the present invention, the colored zirconia sintered body is a zirconia sintered body containing a colorant, and is preferably a zirconia sintered body containing a colorant and a stabilizer.

  As the colored zirconia sintered body, a zirconia sintered body having a required color can be used. Specific examples of the colored zirconia sintered body include red, yellow, orange, green, blue, purple, gray, and black zirconia sintered bodies. Examples of the colored zirconia sintered body having a higher profound feeling and higher aesthetics include black zirconia sintered bodies.

  Next, the manufacturing method of the ceramic joined body of this invention is demonstrated.

  The ceramic joined body of the present invention is a method for producing a ceramic joined body by firing a translucent ceramic and a colored zirconia sintered body, and the translucent ceramic and colored zirconia sintered body are contracted by shrinking the colored zirconia sintered body. It can be manufactured by joining the body.

  The production method of the present invention is a method for producing a ceramic joined body in which a colored zirconia sintered body and a translucent ceramic are fired.

  Hereinafter, the production method of the present invention will be described in detail.

  The colored zirconia sintered body and the translucent ceramic used in the production method of the present invention are both sintered bodies that have been heat-treated at a sintering temperature or higher. By firing the sintered body and the sintered body, the sintered zirconia sintered body and the translucent ceramic before firing can obtain a ceramic joined body without significantly changing the shapes thereof. Thereby, for example, a ceramic joined body having a complicated shape as shown in FIG. 1 can be obtained by the manufacturing method of the present invention.

  In the production method of the present invention, the colored zirconia sintered body is contracted and joined to the translucent ceramic. That is, the manufacturing method of the present invention is a manufacturing method that utilizes thermal shrinkage of a sintered body that has been heat-treated at a sintering temperature or higher.

  Therefore, heat treatment is sufficiently performed at a temperature higher than the sintering temperature, such as a manufacturing method for sintering and bonding a molded body and a molded body, and a manufacturing method for sintering and bonding a molded body and a sintered body. The manufacturing method of the ceramic joined body using the sintering shrinkage of the molded body that is not present and the manufacturing method of the present invention are different manufacturing methods. Thereby, a ceramic joined body can be obtained with almost no change in shape of the colored zirconia sintered body and translucent ceramic before firing. Furthermore, it becomes possible to repeatedly obtain a ceramic joined body having the same shape as compared with the method for producing a ceramic joined body utilizing the sintering shrinkage of the formed body. In other words, the manufacturing method of the present invention is a highly reproducible manufacturing method as compared with the manufacturing method of the ceramic joined body utilizing the sintering shrinkage of the compact.

  The colored zirconia sintered body used in the production method of the present invention has a relative density of 90% or more and 99.9% or less. Furthermore, the relative density is preferably 95% or more, more preferably 96% or more, still more preferably 97% or more, still more preferably 98% or more, and 99% or more. It is particularly preferred. When the relative density of the colored zirconia sintered body is 90% or more and 99.9% or less, it is possible to promote the sintering shrinkage of the colored zirconia sintered body while minimizing the shape change of the colored zirconia sintered body. it can. Thereby, a colored zirconia sintered compact and translucent ceramics can be joined firmly.

  If the colored zirconia sintered body satisfies the above relative density, the coloration can be arbitrarily selected. Specific examples of the colored zirconia sintered body include red, yellow, orange, green, blue, purple, gray, and black zirconia sintered bodies. Examples of the colored zirconia sintered body having a higher profound feeling and higher aesthetics include black zirconia sintered bodies.

  The colorant contained in the colored zirconia sintered body varies depending on the intended coloration. Examples of the colorant include various transition metal oxides and lanthanoid rare earth oxides.

  The colored zirconia sintered body to be fired is not particularly limited as long as its relative density falls within the above range. For example, a colored zirconia sintered body can be produced by molding a zirconia powder containing a colorant and sintering the resulting molded body at an arbitrary temperature of 1200 ° C to 1500 ° C. The relative density of the colored zirconia sintered body can be adjusted by the sintering conditions such as the sintering temperature and the sintering time.

  In the production method of the present invention, a ceramic having a linear transmittance greater than 0% can be used as the translucent ceramic. The higher the linear transmittance of the translucent ceramic, the higher the linear transmittance of the translucent ceramic contained in the obtained ceramic joined body. Therefore, the linear transmittance of the translucent ceramic is preferably at least 10%, more preferably at least 25%, and further preferably at least 30%.

  Furthermore, when manufacturing a ceramic joined body including translucent ceramics having the same transparency as transparent ceramics, the linear transmittance of translucent ceramics is preferably at least 50%, and preferably at least 60%. More preferred is at least 70%.

Examples of such translucent ceramics include polycrystalline bodies such as yttria sintered bodies, spinel sintered bodies, yttria-alumina-garnet sintered bodies, translucent alumina sintered bodies, or translucent zirconia sintered bodies. The light-transmitting alumina sintered body or the light-transmitting zirconia sintered body is preferable, and the light-transmitting zirconia sintered body is more preferable. More preferable translucent zirconia sintered bodies include yttria-containing zirconia sintered bodies, titania (TiO ₂ ), and yttria-containing zirconia sintered bodies.

  The manufacturing method is not particularly limited as long as the translucent ceramic has the above-described linear transmittance. As a manufacturing method of translucent ceramics, for example, a manufacturing method in which a raw material powder is molded and subjected to primary sintering and then subjected to HIP treatment.

  In the production method of the present invention, the colored zirconia sintered body and the translucent ceramic are preferably fired at a firing temperature exceeding 1100 ° C. The firing temperature is more preferably 1200 ° C. or higher, and further preferably 1250 ° C. or higher. When the firing temperature is higher than 1100 ° C., sintering shrinkage of the colored zirconia sintered body tends to occur. As a result, the colored zirconia sintered body and the translucent ceramic are easily joined.

  As the firing temperature is higher, sintering shrinkage of the colored zirconia sintered body occurs. Therefore, the colored zirconia sintered body is easily joined firmly by the translucent ceramic. When the firing temperature is 1500 ° C. or lower, preferably 1450 ° C. or lower, more preferably 1400 ° C. or lower, a ceramic joined body in which the colored zirconia sintered body and the translucent ceramic are firmly joined can be obtained.

In addition, when baking temperature is high, the transparency may change with translucent ceramics to be used. When using translucent ceramics whose transparency changes depending on the firing temperature, considering the relationship between the colored zirconia sintered body and translucent ceramics, and the transparency of translucent ceramics, It is preferable to determine the firing temperature within the range. For example, when titania (TiO ₂ ) and yttria-containing zirconia sintered bodies are used as the translucent ceramics, the transparency of the translucent ceramics can be particularly increased by setting the firing temperature to 1300 ° C. or lower. . On the other hand, by performing firing at a temperature exceeding 1300 ° C., the transparency of the translucent ceramic can be suppressed.

  The firing atmosphere is preferably an oxidizing atmosphere or an inert atmosphere. Compared with the case where firing is performed in an atmosphere other than an inert atmosphere or an oxidizing atmosphere, that is, a reducing atmosphere, firing in an oxidizing atmosphere or the like is less likely to cause deterioration or cracking of the colored zirconia sintered body. Moreover, by making the firing atmosphere an oxidizing atmosphere, a ceramic joined body can be manufactured at a higher firing temperature regardless of the type of translucent ceramics.

  The firing method can be performed by any method. Examples of the firing method include normal pressure firing, microwave firing or hot isostatic pressing (hereinafter referred to as “HIP treatment”). The firing method is preferably atmospheric firing or HIP treatment. Moreover, in order to join a colored zirconia sintered compact and translucent ceramics more firmly, it is more preferable to perform baking by HIP processing.

  When firing is performed by HIP treatment, conditions other than temperature can be set as appropriate. For example, the HIP treatment pressure can be 50 MPa or more and 200 MPa or less, and the HIP treatment time can be 0.5 hours or more and 10 hours or less. An inert gas such as argon or nitrogen can be used as the pressure medium.

  The atmosphere of the HIP process is greatly affected by the pressure medium. Therefore, in the HIP process using an inert gas as a pressure medium, the atmosphere becomes an inert atmosphere. However, in the case where a reducing substance is contained in a component for HIP processing such as a carbon heater, the atmosphere of HIP becomes a weak reducing atmosphere even when an inert gas is used as a pressure medium.

  However, in the HIP process, the sample during the HIP process can be placed in a specific atmosphere by appropriately selecting a container in which the sample is placed. For example, by using a container made of oxide ceramics such as alumina, zirconia, or mullite, the sample during the HIP treatment can be placed in an inert atmosphere. On the other hand, by using a carbon container, the sample during the HIP process can be placed in a reducing atmosphere.

  After the heat treatment, an annealing treatment can be performed as necessary. Thereby, the transparency of the translucent ceramics in a ceramic joined body can be mentioned. The conditions for the annealing treatment can be exemplified by a treatment temperature of 1000 ° C. or more and 1200 ° C. or less and a treatment time of 0.5 hours or more and 2 hours or less in an oxygen atmosphere such as air.

  In the production method of the present invention, the colored zirconia sintered body and the translucent ceramic are preferably disposed and fired so that the colored zirconia sintered body sandwiches the translucent ceramic. Furthermore, it is more preferable that the colored zirconia sintered body is sandwiched between the translucent ceramics, and is disposed and fired so that a gap is formed between the colored zirconia sintered body and the translucent ceramics.

  As a method of arranging and firing colored zirconia sintered body and translucent ceramic so that colored zirconia sintered body sandwiches translucent ceramic, formed between translucent ceramic and colored zirconia sintered body And a second gap between the translucent ceramic and the colored zirconia sintered body formed symmetrically with the first gap with the center of the translucent ceramic as a center of symmetry. It is particularly preferable to dispose the colored zirconia sintered body and the translucent ceramic so as to satisfy the formula (1).

L ≦ (1-ρ ^1/3 ) (1)
(L: Ratio of the total length of the first gap and the second gap to the shortest length of the end of the colored zirconia in contact with the second gap from the end of the colored zirconia sintered body in contact with the first gap, ρ: Relative density of colored zirconia sintered body before firing (-))

  By arranging the colored zirconia sintered body and the translucent ceramic in this manner, the bonding between the colored zirconia sintered body and the translucent ceramic becomes stronger due to the sintering shrinkage of the colored zirconia sintered body. . In addition, the colored zirconia sintered body and the translucent ceramic can be more efficiently joined by sintering shrinkage of the colored zirconia sintered body.

  Hereinafter, a preferable arrangement method when firing the colored zirconia sintered body and the translucent ceramic will be described with reference to FIGS.

  The colored zirconia sintered body is preferably disposed so as to sandwich the translucent ceramic. Alternatively, the colored zirconia sintered body may be disposed so as to surround the translucent ceramic, and the colored zirconia sintered body may sandwich the translucent ceramic.

  As such an arrangement, for example, an arrangement as shown in FIGS. 2 (a) and 2 (b), the colored zirconia sintered body is arranged so as to sandwich the translucent ceramic. 2C and 2D, the colored zirconia sintered body is disposed so as to sandwich the translucent ceramic, and the colored zirconia sintered body surrounds the translucent ceramic.

  The colored zirconia sintered body and the translucent ceramic are arranged so that a gap is formed between the colored zirconia sintered body and the translucent ceramic. A gap formed between the colored zirconia sintered body and the translucent ceramic (hereinafter, also simply referred to as “gap”) is a space between the colored zirconia sintered body and the translucent ceramic. In FIGS. 2A to 2D, a portion indicated by 3 is a portion corresponding to the gap. In the arrangements shown in FIGS. 2A and 2B, there is no clear boundary between the gap and a space other than the gap. Therefore, in FIGS. 2A and 2B, the space near the range surrounded by the broken line can be regarded as a gap.

An arbitrary range is defined as the first gap in the gap. Furthermore, a gap formed symmetrically with the first gap with the center of the translucent ceramic as the center of symmetry is defined as a second gap. In Figure 3, the range, for example shown in S ₁ and the first gap. In this case, the range indicated by S ₂ or S ₂ ′ corresponds to the second gap.

The center of the translucent ceramic means the center point of the translucent ceramic, a line passing through the central point of the translucent ceramic (hereinafter referred to as the center line), and a surface passing through the central point of the translucent ceramic (hereinafter referred to as the center). , Center plane). In FIG. 3, S ₂ is a gap formed at a position symmetrical to S ₁ with the center line of the translucent ceramic as the center of symmetry. That is, the straight line passing through the center point of the translucent ceramic as the center of symmetry, the gap formed at the position of S ₁ and symmetry is S _2. On the other hand, S ₂ ′ is a gap formed at a position symmetrical to S ₁ with the center point of the translucent ceramic as the center of symmetry. In other words, a straight line connecting S ₁ and the center point of the translucent ceramic and formed at a position symmetrical to S ₁ with respect to the center point is S ₂ ′.

  When the second gap is defined with the center line or the center plane as the center of symmetry, it is preferable that a straight line connecting the first gap and the second gap passes through the translucent ceramic. As a result, the colored zirconia sintered body sandwiches the translucent ceramic.

  Note that there may be a plurality of gaps corresponding to the second gap as shown in FIG. In this case, any one of the gaps may be set as the second gap so as to satisfy the relationship of the expression (1).

L ≦ (1-ρ ^1/3 ) (1)
(L: Ratio of the total length of the first gap and the second gap to the shortest length of the end of the colored zirconia in contact with the second gap from the end of the colored zirconia sintered body in contact with the first gap, ρ: Relative density of colored zirconia sintered body before firing (-))

Note that when the other transparent gap is not formed at a position symmetrical to one gap with the center of the translucent ceramic as the center of symmetry, the gap cannot be the first gap. For example, in FIG. 3, the gap range shown in S ₃ are not formed gap position where the Symmetrically. Such a gap cannot be the first gap.

  Thus, in the manufacturing method of this invention, it is preferable to arrange | position a colored zirconia sintered compact and translucent ceramic so that a 1st clearance gap and a 2nd clearance gap may be formed in a symmetrical position. This makes it easy for the colored zirconia sintered body to shrink so as to sandwich the translucent ceramic when fired. As a result, the colored zirconia sintered body and the translucent ceramic can be more firmly joined.

  Furthermore, the ratio of the total length of the first gap and the second gap to the shortest length of the end of the colored zirconia in contact with the second gap from the end of the colored zirconia sintered body in contact with the first gap is the above. It is preferable to arrange so as to satisfy the formula (1).

The end of the colored zirconia sintered body in contact with the gap is an arbitrary point of the colored zirconia sintered body in contact with each gap. For example, the points indicated by E ₁ and E ₂ (or E ₂ ′) in FIG. E ₁ is an end of the colored zirconia sintered body in contact with S ₁ , and an end of the colored zirconia sintered body in contact with S ₂ (or S ₂ ′) is E ₂ (or E ₂ ′).

When the second gap is S ₂ , the length connecting two points E ₁ and E ₂ with a straight line is a colored zirconia in contact with the second gap from the end of the colored zirconia sintered body in contact with the first gap. Is the shortest length (L _total ). Note that L _total needs to be a straight line passing through the translucent ceramic.

The total length of the first gap and the second gap is the total length from the end of the colored zirconia sintered body in contact with each gap to the translucent ceramic in L _total . For example, in FIG. 3, if the second gap was S _2, L ₁ corresponds to the length of the first gap, also, L ₂ corresponds to the length of the second gap. The sum of these (L ₁ + L ₂ ) is the total length of the first gap and the second gap.

The ratio of the total length (L ₁ + L ₂ ) of the first gap and the second gap to L _total is L in the expression (1). When L satisfies the relationship of the formula (1), the bonding between the colored zirconia sintered body and the translucent ceramic tends to become stronger due to the shrinkage of the colored zirconia sintered body by firing.

  The ceramic joined body of the present invention is a joined body composed of a translucent zirconia sintered body having high transparency and a colored zirconia sintered body. Therefore, the ceramic joined body of the present invention has not only high designability but also excellent aesthetics. Further, the ceramics are directly and firmly bonded without using a bonding material. Therefore, it is suitable for a window member of a timepiece that requires high strength, a display unit of an electronic device, and the like. The joined body of the present invention can be suitably used as various members including exterior parts of electronic devices in addition to the use of jewelry and watch members because of high aesthetics and design.

  Furthermore, the method for producing a ceramic joined body of the present invention can also be applied as a novel ceramic joining method.

Shape example of ceramic joined body of the present invention The figure which showed an example of the preferable arrangement | positioning in the manufacturing method of this invention The figure which showed the example of the positional relationship of a colored zirconia sintered compact and translucent ceramics in the preferable arrangement | positioning in the manufacturing method of this invention. Schematic diagram of black zirconia sintered body used in Example 1 External appearance of the ceramic joined body obtained in Example 1 EPMA measurement results at the interface of Example 2 (scale in the figure is 200 μm) SEM observation drawing of the ceramic joined body of Example 2 (scale in the figure is 1 μm) X-ray diffraction pattern of the black zirconia sintered body of Comparative Example 2

  Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples.

(Relative density)
The density of the sample was measured using the Archimedes method. The obtained density was determined as a relative density with respect to the true density. The true density of the black zirconia sintered body is 6.06 g / cm ³ , the true density of the yttria-containing translucent zirconia sintered body is 6.01 g / cm ³ , and the yttria- and titania-containing translucent zirconia sintered body is used. The true density of the body was 5.83 g / cm ³ .

(Joint strength)
The joint strength was measured according to the biaxial bending strength measurement (ISO / DIS6872). In the biaxial bending strength measurement, the support radius was 22 mm in diameter. Further, a support was installed at the joint of the colored zirconia sintered body, and the measurement was performed so that a load was applied to the center of the translucent ceramic.

The measurement sample used was a mirror polished on both sides with a surface roughness Ra = 0.02 μm or less.
(Linear transmittance)
A ceramic joined body that was mirror-polished to a surface roughness Ra = 0.02 μm or less was used as a measurement sample. The linear transmittance was measured using a haze meter (Nippon Denshoku, NDH5000). The light source used was D65 light.
(Measurement of L)
L was measured by microscopic observation with a measuring microscope (Nikon, MM-800). As shown in FIG. 2 (c) or (d), translucent ceramics were placed inside the colored zirconia sintered body processed into a frame shape. The sample after placement was observed with an electron microscope.

Any gap between the colored zirconia sintered body and the translucent ceramics were considered first gap (corresponding to S ₁ in FIG. 3). End of the colored zirconia sintered body in contact with the gap located on a straight line passing through (equivalent to E ₁ in FIG. 3) and the center point of the translucent ceramics, a gap a second which is yet formed in the gap and the target It was set as a gap (corresponding to S ₂ ′ in FIG. 3). The linear distance between the end of the colored zirconia sintered body in contact with the first gap and the end of the colored zirconia sintered body in contact with the second gap (corresponding to E ₂ ′ in FIG. 3) is determined, and this is _expressed as L _total did.

Further, in the straight line, and it obtains distances between the end and the translucent ceramic colored zirconia sintered body in contact with the first gap, which was used as a L _1. Also, determine the distance between the end and the translucent ceramic colored zirconia sintered body in contact with the second gap, which was used as a L _2.

L in the formula (1) was determined from the obtained L _total , L ₁ and L ₂ .

Example 1
(Production of black zirconia sintered body)
Black zirconia powder (manufactured by Tosoh Corporation, TZ-Black) was molded at a pressure of 50 MPa by a mold press. The black zirconia powder after molding was molded by a cold isostatic press (CIP) with a pressure of 200 MPa to obtain a plate-shaped molded body having a length of 30 mm and a width of 40 mm. The obtained molded body was sintered under normal pressure to obtain a black zirconia sintered body having a relative density of 98.7%.

  This black zirconia sintered body was machined to have a rectangular hollow portion having a length of 14 mm, a width of 22 mm, and a thickness of 1.15 mm, and a frame-shaped black zirconia sintered body having a length of 28 mm, a width of 36 mm, and a thickness of 1.15 mm. Obtained. The schematic diagram of the obtained black zirconia sintered compact is shown in FIG.

(Production of translucent zirconia sintered body)
10 mol% yttria-containing zirconia powder (manufactured by Tosoh, TZ-10YS) and high-purity titania powder were added at 10 mol% with respect to zirconia, followed by ball mill mixing for 72 hours with zirconia balls having a diameter of 10 mm in an ethanol solvent, and then dried. The raw material powder was used.

  The raw material powder was molded at a pressure of 50 MPa by a die press and then molded at a pressure of 200 MPa by a cold isostatic press to obtain a plate-like molded body having a length of 50 mm, a width of 40 mm, and a thickness of 2 mm.

  The obtained plate-like molded body was primarily sintered in the atmosphere at a temperature rising rate of 100 ° C./h, a sintering temperature of 1350 ° C., and a sintering time of 2 hours to obtain a primary sintered body. The obtained primary sintered body had a relative density of 94%, an average particle size of 3 μm or less, and the crystal phase was a cubic phase and a tetragonal phase.

  Next, the primary sintered body was subjected to HIP treatment at a temperature of 1650 ° C., a pressure of 150 MPa, and a holding time of 1 hour to obtain a translucent zirconia sintered body. Note that argon gas having a purity of 99.9% was used as the pressure medium, and the temporary sintered body was placed in a carbon container with a lid to perform HIP treatment.

  The crystal phase of the obtained translucent zirconia sintered body was a single phase having a cubic fluorite structure.

(Production of ceramic joined body)
A black zirconia sintered body and a translucent zirconia sintered body were arranged. The L and ρ at this time are shown in Table 1.
This was subjected to HIP treatment and fired to obtain a ceramic joined body.

  The HIP treatment was performed at a temperature of 1200 ° C., a pressure of 150 MPa, and a holding time of 1 hour. Note that argon (Ar) gas having a purity of 99.9% was used as the pressure medium for the HIP treatment. In the HIP process, the sample was placed in an alumina container. After the HIP treatment, the HIP-treated body obtained at 1000 ° C. for 1 hour in the atmosphere was annealed. The results are shown in Table 1, and the obtained ceramic joined body is shown in FIG.

  It was found that due to the sintering shrinkage of the black zirconia sintered body, the black zirconia sintered body and the translucent ceramic were joined, and the obtained ceramic joined body provided high joint strength. Moreover, the linear transmittance | permeability of the translucent zirconia sintered compact is 70% or more, and it turned out that it has high transparency.

Example 2
A black zirconia sintered body was obtained in the same manner as in Example 1 except that the relative density of the black zirconia sintered body was 99.0%. Further, a translucent zirconia sintered body was obtained in the same manner as in Example 1.

  The obtained black zirconia sintered body and translucent zirconia sintered body were fired in the same manner as in Example 1 except that L was arranged so as to have the value shown in Table 1 to obtain a ceramic joined body. It was.

  The composition analysis by EPMA was implemented about the joining interface of the obtained ceramic joined body. The results are shown in FIG. It was found that there was no bonding phase at the interface between the black zirconia sintered body and the translucent zirconia sintered body, and there was no element diffusion at the interface between the two.

  Further, the obtained ceramic joined body was etched at 1300 ° C. for 1 hour and then observed with an electron microscope. The results are shown in FIG.

  From FIG. 7, it can be confirmed that the ceramic joined body of the present invention comprises a translucent zirconia sintered body having crystal particles having a particle diameter of 1 μm or more and a black zirconia sintered body having crystal particles having a particle diameter of less than 1 μm. . Further, it was found that the translucent zirconia sintered body and the black zirconia sintered body did not contain particles other than these, and both were directly joined.

Example 3
(Production of black zirconia sintered body)
Black zirconia powder was molded by a mold press at a pressure of 50 MPa. Thereafter, the black zirconia powder after molding was molded by a cold isostatic press (CIP) with a pressure of 200 MPa to obtain a disk-shaped molded body having a diameter of 40 mm. The obtained molded body was sintered under normal pressure to obtain a black zirconia sintered body having a relative density of 99.1%.

  This black zirconia sintered body was machined to obtain a frame-shaped sintered body having a diameter of 25 mm and a thickness of 1 mm having a circular hollow portion having a diameter of 15 mm and a thickness of 1 mm.

(Production of translucent zirconia sintered body)
As the zirconia powder, 8 mol% yttria-containing zirconia powder (manufactured by Tosoh, TZ-8Y) produced by the hydrolysis method was used, the shape of the molded body was a disk shape with a diameter of 30 mm, and the processing temperature was A translucent zirconia sintered body was obtained in the same manner as in Example 1 except that the HIP treatment was performed at 1650 ° C.

(Production of ceramic joined body)
Similar to Example 1 except that the obtained black zirconia sintered body and translucent zirconia sintered body were arranged so as to have the value of L shown in Table 2, and the HIP treatment temperature was 1400 ° C. The ceramic joined body was obtained by firing by various methods.

  Table 3 shows the results of the joint study. It turned out that the ceramic joined body which has a 8 mol% yttria containing zirconia sintered compact as translucent ceramic becomes a highly transparent ceramic joined body.

Example 4
A black zirconia sintered body was obtained in the same manner as in Example 3 except that the relative density of the black zirconia sintered body was 96.6%. Moreover, the translucent zirconia sintered compact was obtained by the same method as Example 3.

  The obtained black zirconia sintered body and translucent zirconia sintered body were arranged so as to have the value of L shown in Table 2, and were sintered at normal pressure in the atmosphere at 1400 ° C. for 1 hour. Except for the above, a ceramic joined body was obtained in the same manner as in Example 3.

Example 5
A black zirconia sintered body and a translucent zirconia sintered body were obtained in the same manner as in Example 1.

  Similar to Example 1 except that the obtained black zirconia sintered body and translucent zirconia sintered body were arranged so as to have the value of L shown in Table 2 and were subjected to HIP treatment at 1250 ° C. A ceramic joined body was obtained by various methods.

Example 6
A black zirconia sintered body and a translucent zirconia sintered body were obtained in the same manner as in Example 1.

  Similar to Example 1 except that the obtained black zirconia sintered body and translucent zirconia sintered body were arranged so as to have the value of L shown in Table 3 and were subjected to HIP treatment at 1300 ° C. A ceramic joined body was obtained by various methods.

Example 7
A black zirconia sintered body was obtained in the same manner as in Example 1 except that the relative density of the black zirconia sintered body was 97.4%. Moreover, the translucent zirconia sintered compact was obtained by the method similar to Example 1. FIG.

  Similar to Example 1 except that the obtained black zirconia sintered body and translucent zirconia sintered body were arranged so as to have the value of L shown in Table 3 and were subjected to HIP treatment at 1300 ° C. A ceramic joined body was obtained by various methods.

Example 8
A black zirconia sintered body was obtained in the same manner as in Example 1 except that the relative density of the black zirconia sintered body was 96.6%. Moreover, the translucent zirconia sintered compact was obtained by the method similar to Example 1. FIG.

  Similar to Example 1 except that the obtained black zirconia sintered body and translucent zirconia sintered body were arranged so as to have the value of L shown in Table 3 and were subjected to HIP treatment at 1300 ° C. A ceramic joined body was obtained by various methods.

Example 9
A black zirconia sintered body was obtained in the same manner as in Example 34 except that the relative density of the black zirconia sintered body was 98.6%. Moreover, the translucent zirconia sintered compact was obtained by the method similar to Example 1. FIG.

  Similar to Example 3 except that the obtained black zirconia sintered body and translucent zirconia sintered body were arranged so as to have the value of L shown in Table 3 and were subjected to HIP treatment at 1350 ° C. A ceramic joined body was obtained by various methods.

Example 10
A black zirconia sintered body and a translucent zirconia sintered body were obtained in the same manner as in Example 1.

  Except that the obtained black zirconia sintered body and translucent zirconia sintered body were arranged so as to have the value of L shown in Table 3, and HIP-treated at 1450 ° C., the same as in Example 1. A ceramic joined body was obtained by various methods.

Example 11
A black zirconia sintered body and a translucent zirconia sintered body were obtained in the same manner as in Example 1.

  Similar to Example 1 except that the obtained black zirconia sintered body and translucent zirconia sintered body were arranged so as to have the value of L shown in Table 3 and were subjected to HIP treatment at 1500 ° C. A ceramic joined body was obtained by various methods.

Comparative Example 1
A black zirconia sintered body was obtained in the same manner as in Example 1 except that the relative density of the black zirconia sintered body was 98.6%. Moreover, the translucent zirconia sintered compact was obtained by the method similar to Example 1. FIG.

  The obtained black zirconia sintered body and translucent zirconia sintered body were arranged so as to have a value of L shown in Table 4, and the sample was placed in a carbon container and HIP was obtained at 1400 ° C. A ceramic joined body was obtained in the same manner as in Example 1 except for the treatment.

  After the HIP treatment, the black zirconia sintered body was cracked and a ceramic joined body was not obtained. Furthermore, the black zirconia sintered body became brittle.

Comparative Example 2
A black zirconia sintered body was obtained in the same manner as in Example 3 except that the relative density of the black zirconia sintered body was 98.5%. Moreover, the translucent zirconia sintered compact was obtained by the same method as Example 3.

  A ceramic joined body was obtained by the same method as in Comparative Example 1 except that the obtained black zirconia sintered body and translucent zirconia sintered body were arranged so as to have the values of L shown in Table 4. .

  After the HIP treatment, the black zirconia sintered body was cracked and a ceramic joined body was not obtained.

  The result of the XRD measurement of this comparative example is shown in FIG. As is clear from FIG. 8, in the sintered body of this comparative example, a peak derived from an impurity other than the black zirconia peak (◎ in FIG. 8) (▲ in FIG. 8) was confirmed.

  From this, it was found that in this comparative example, not only a ceramic joined body was not obtained but also an impurity layer was formed.

Comparative Example 3
A black zirconia sintered body and a translucent zirconia sintered body were obtained in the same manner as in Example 1.

  Similar to Comparative Example 1 except that the obtained black zirconia sintered body and translucent zirconia sintered body were arranged so as to have the values of L shown in Table 5 and HIP-treated at 1200 ° C. A ceramic joined body was obtained by various methods.

  After the HIP treatment, the black zirconia sintered body was cracked and a ceramic joined body was not obtained. Further, as a result of the XRD measurement, peaks other than the black zirconia sintered body were confirmed.

Comparative Example 4
A black zirconia sintered body was obtained in the same manner as in Example 3 except that the relative density of the black zirconia sintered body was 98.7%. Moreover, the translucent zirconia sintered compact was obtained by the same method as Example 3.

  Example 3 except that the obtained black zirconia sintered body and translucent zirconia sintered body were arranged so as to have the value of L shown in Table 5 and that the HIP treatment temperature was 1200 ° C. A ceramic joined body was obtained by the same method as above.

  It turned out that a black zirconia sintered compact and a translucent zirconia sintered compact do not join, and a ceramic joined body cannot be obtained. The results are shown in Table 5.

Comparative Example 5
A black zirconia sintered body and a translucent zirconia sintered body were obtained in the same manner as in Example 1.

  A ceramic joined body was obtained by the same method as in Example 1 except that the obtained black zirconia sintered body and translucent zirconia sintered body were arranged so as to have the values of L shown in Table 5.

  It turned out that a black zirconia sintered compact and a translucent zirconia sintered compact do not join, and a ceramic joined body cannot be obtained. The results are shown in Table 5.

Comparative Example 6
A black zirconia sintered body was obtained in the same manner as in Example 3 except that the relative density of the black zirconia sintered body was 98.5%. Moreover, the translucent zirconia sintered compact was obtained by the same method as Example 3.

  Example 3 except that the obtained black zirconia sintered body and translucent zirconia sintered body were arranged so as to have the value of L shown in Table 5 and that the HIP treatment temperature was 1100 ° C. A ceramic joined body was obtained by the same method as above.

  It turned out that a black zirconia sintered compact and a translucent zirconia sintered compact do not join, and a ceramic joined body cannot be obtained. The results are shown in Table 5.

  The ceramic joined body of the present invention can be used as various members and ornaments.

1: colored zirconia sintered body 2: translucent ceramics 3: gap formed between colored zirconia sintered body and translucent ceramics ◎: zirconia peak ▲: peak derived from impurities

Claims (15)

  A ceramic joined body comprising a colored zirconia sintered body and a translucent ceramic.   2. The ceramic joined body according to claim 1, wherein the colored zirconia sintered body is joined to the translucent ceramic without using a joining material.   3. The ceramic joined body according to claim 1, wherein the translucent ceramic has a sample thickness of 1 mm and a linear transmittance of D65 light of at least 50%.   4. The ceramic joined body according to claim 1, wherein the translucent ceramic is a translucent zirconia sintered body.   The ceramic joined body according to any one of claims 1 to 4, wherein the colored zirconia sintered body is a black zirconia sintered body.   A method for producing a ceramic joined body for firing a translucent ceramic and a colored zirconia sintered body, wherein the colored zirconia sintered body is contracted to join the translucent ceramic and the colored zirconia sintered body. The joining method of the ceramic joined body of Claim 1 thru | or 5.   The manufacturing method according to claim 6, wherein firing is performed in an inert atmosphere or an oxidizing atmosphere at a temperature exceeding 1100 ° C.   The method according to claim 6 or 7, wherein the colored zirconia sintered body and the translucent ceramic are disposed and fired so that the colored zirconia sintered body sandwiches the translucent ceramic.   The manufacturing method according to claim 6, wherein the relative density of the colored zirconia sintered body is 90% or more and 99.9% or less.   The manufacturing method according to claim 6 or 7, wherein the baking is performed by HIP treatment. A member using the ceramic joined body according to claim 1. A jewelery using the member of claim 11.   A method for joining a colored zirconia sintered body and a translucent ceramic, comprising shrinking the colored zirconia sintered body to join the translucent ceramic and the colored zirconia sintered body.   The joining method according to claim 13, wherein firing is performed in an inert atmosphere or an oxidizing atmosphere at a temperature exceeding 1100 ° C.   The joining method according to claim 13 or 14, wherein the colored zirconia sintered body and the translucent ceramic are disposed and fired so that the colored zirconia sintered body sandwiches the translucent ceramic.

Images