JPH11130546A - Jig for baking functional ceramic component and production of the jig - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject jig intended to improve the dimensional accuracy of a to-be-baked material without deteriorating its characteristics, by providing a ceramic substrate surface serving as a platform for a to-be-baked material with a coating layer made of a material inert to the to-be-baked material and by providing the surface of the coating layer with fine lattice-like grooves of a specific area. SOLUTION: This jig has the following scheme: the surface of a coating layer on a substrate is provided with fine grooves having an area accounting for 30-80% of the area of a platform for a to-be-baked material (namely, the surface of the coating layer), it is preferable that each of the grooves is 0.2-3.0 mm in width and 0.2-3.0 mm in depth and they are arranged 0.5-2.5 mm apart from the adjacent groove; for this purpose, the platform of the ceramic substrate is laid with a net of necessary mesh which, in turn, is coated with a slurry comprising materials inert to a to-be- coated material so as to fill in gaps, and after the slurry gets non-fluid, the net is removed and the resultant layer is dried and baked; the material of the substrate consists of a ceramic such as alumina or cordierite, the apparent porosity of the coating layer is set at >=10%, and the material of the coating layer is e.g. high-purity zirconia.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to jigs such as shelves and trays used for firing functional ceramic parts such as electric and electronic parts, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In recent years, functional ceramic parts such as electric and electronic parts to be fired have been reduced in size.
The reactivity with the firing jig is more likely to become a problem than before. In addition, the dimensional accuracy required for functional ceramic parts is becoming stricter year by year, and the difference in firing shrinkage of the object to be fired between the contact part and the non-contact part with the jig, which was not a problem before, may be a problem. More. Conventionally, as a jig for firing a functional ceramic component that solves the above-mentioned problems, an object to be fired on a substrate made of alumina or mullite ceramic is formed in an oblique lattice-like uneven pattern, and the uneven pattern surface is formed. A coating layer made of a zirconia-based coating material formed thereon (see JP-A-6-159950), or a material that is hardly reactive with the material to be fired, There is known a coating layer having a surface having an uneven structure (height: 200 to 1500 μm) (see JP-A-6-281359). The former jig is manufactured by coating a zirconia-based coating material on a surface of a substrate, which is formed into an oblique lattice-like uneven pattern by press working, and the latter jig is coated with a zirconia coating material. A flat coating layer made of a material that is hardly reactive with the object to be fired is formed on the fired object mounting surface, and the coating layer is blasted with an abrasive through a mask, or the coating layer is coated with a mask through the mask. It is manufactured by coating a coating material made of the same material as described above.

[0003]

However, in the former jig for firing a functional ceramic component, the unevenness is formed on the surface of the substrate on which the object is to be fired, and then the surface is coated with an uneven pattern. In the case of a rough uneven surface, it is difficult to coat with a uniform thickness, and in the latter case, a flat coating layer formed on the base is subjected to blasting with a polishing material via a mask or coating treatment of the coating material through a mask. In order to obtain a fine uneven structure, it is difficult to make the window of the mask small, so that the surface of the coating layer cannot be formed into a fine and uniform uneven structure in any case. In addition to the reaction occurring in the contact part of the sintering and the deterioration of the properties of the object to be baked due to the movement of components, the dimensional accuracy decreases due to the difference in firing shrinkage of the object to be baked between the contact part and the non-contact part with the firing jig. Ah . Therefore, an object of the present invention is to provide a firing jig for a functional ceramic component capable of improving the dimensional accuracy without causing deterioration in characteristics of an object to be fired, and a method for manufacturing the same.

[0004]

In order to solve the above-mentioned problems, a jig for firing a functional ceramic component according to the present invention is provided on a surface of a substrate made of ceramics on which an object to be fired is hardly reactive. In a jig for firing a functional ceramic component having a coating layer made of a material, fine grid-shaped grooves having an area of 30 to 80% of the area of the surface on which the object is to be fired are formed on the surface of the coating layer. It is characterized by having been done. The concave groove has a width of 0.2 to 3.0 mm and a depth of 0.2 to 3.0 m.
m, and the interval is preferably 0.5 to 2.5 mm. On the other hand, the first method for manufacturing a jig for firing a functional ceramic component includes a method of laying a mesh of a required mesh on a surface of a substrate made of ceramic on which an object to be fired is placed, and a coating made of a material that is hardly reactive with the object to be fired. The method is characterized in that the material slurry is applied to a mesh, and after the fluidity of the coating material slurry is lost, the mesh is removed, dried and baked. A second method for manufacturing a jig for firing a functional ceramic component includes laying a flammable net of a required mesh on a surface of the base made of ceramics on which the object is to be fired, and forming a material that is difficult to react with the object to be fired. Is coated on a mesh, dried and baked.

On the surface of the coating layer, the area of the surface on which the object to be fired is mounted is
By forming the fine grid-shaped concave grooves having an area of 0 to 80%, the surface of the coating layer exhibits a fine and uniform uneven structure, and the contact area with the object to be fired is reduced, and There are multiple points of support for the fired material, and a passage is provided that has low resistance to the decomposition gas and evaporated water of the binder from the fired material.

The material of the substrate is required to have thermal shock resistance, bend creep resistance, light weight, low heat capacity, and the like. From such a viewpoint, ceramics such as alumina, alumina-mullite, cordierite, magnesia, magnesia-spinel, and silicon carbide are used as the material of the base. In addition, since the substrate is more advantageous in absorbing the moisture of the coating material slurry when forming the coating layer,
The apparent porosity is preferably 10% or more. in addition,
From the viewpoint of light weight and low heat capacity, it is advantageous that the apparent porosity is as large as possible within a range where the strength can be maintained.
When the apparent porosity of the substrate is less than 10%, the decrease in the water content of the coating material slurry is slow, and it takes a long time for the coating material to be fixed on the surface of the substrate on which the object to be fired is placed. In the coating material slurry, the mixed raw material may separate due to the difference in sedimentation speed caused by the specific gravity and particle size difference,
Not preferred.

As the material of the coating layer, high-purity zirconia, alumina, magnesia or the same material as the material to be fired,
Alternatively, a mixture thereof is used. Here, zirconia has low reactivity, but has a high density. Therefore, if the entire jig is made of zirconia, the weight of the zirconia increases and the durability of the jig itself is reduced. Moreover, it is weak to rapid heating and rapid cooling, and the material itself is expensive. For this reason, it is effective to form a zirconia layer only on a part or the entire surface of the jig.

If the area of the groove on the surface of the coating layer is less than 30% of the area of the surface on which the object to be fired is placed, there is no effect of reducing the contact area, and the object to be fired reacts with the jig. The characteristics are deteriorated, and the dimensional accuracy is reduced due to unevenness in firing shrinkage. On the other hand, if it exceeds 80%, the load per unit area received on each contact surface becomes large, and the problem that the contact portions of the object to be fired are dented or the contact portions bend and deform easily occurs.

The width and the interval of the concave groove are made narrower as the size of the object to be fired becomes smaller, and at least 1/4 or less of the length of the short dimension of the contact surface of the object to be fired with the firing jig. Desirably. However, when the width and gap of the concave groove are fine, the difficulty in manufacturing increases and the cost increases, so the width is 0.2 m.
m and an interval of 0.5 mm or more. The groove has a width of 3.0
When the distance exceeds 0.5 mm and the interval is less than 0.5 mm, the area of the concave groove exceeds 80% of the area of the surface on which the object to be fired is placed, while the width of the groove is 0.1 mm.
If the distance is less than 2 mm and the distance exceeds 2.5 mm, the area of the concave groove becomes less than 30% of the area of the surface on which the object to be fired is placed, thus causing the above-mentioned problem. If the depth of the concave groove is less than 0.2 mm, the decomposition gas and evaporated water of the binder of the material to be fired are difficult to escape, while if it exceeds 2.5 mm, the convex portion becomes brittle or difficult to manufacture. The degree goes up. The thickness of the bottom of the concave groove in the coating layer is preferably 0.1 to 2.0 mm.
If the thickness is less than 0.1 mm, the properties of the material to be fired will be degraded by the base component, while if it exceeds 2.0 mm, the thickness of the entire coating layer will be large, and peeling will occur.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to specific examples and comparative examples. Example 1 First, alumina (Al ₂ O ₃ ) and mullite (3Al ₂
O ₃ , 2SiO ₂ ) as a main component, a ceramic sintered body having an Al ₂ O ₃ ratio of 90 wt% and an apparent porosity of 20%, and a shape of 300 mm × 300 mm × 10 mm
Is formed, and a polypropylene mesh (wire diameter:
(0.5 mm, interval: 1.0 mm). Next, yttria (Y ₂ O ₃ ) partially stabilized zirconia (ZrO ₂ ) having an average particle size of 2 μm (ZrO ₂ : 92 wt%, Y
₂ O ₃ : 8 wt%), an external ratio of 30 wt% of water and 2.5 wt% of PVA as a binder were added, and the mixture was mixed by a ball mill for 3 hours to prepare a coating material slurry. Then, it was applied to the mesh of the net laid on the shelf board base. Next, at the stage where the moisture in the coating material slurry was sucked into the pores of the shelf substrate and the fluidity of the coating material slurry was lost and the coating material was fixed on the shelf substrate, the net was removed. On the surface of the coating material on the shelf board base, concave grooves having a width of about 0.5 mm, a depth of about 0.5 mm, and an interval of about 1.0 mm were formed in a lattice shape. Next, the shelf board substrate was dried with hot air at a temperature of 100 ° C. for 5 hours. By this drying, moisture was evaporated, the PVA was cured, and the coating material was solidified. Next, the base material for the shelf board in which the coating material was solidified was held in an air atmosphere at a temperature of 1400 ° C. for 3 hours (elevation and cooling rate: about 200 ° C./hour), and the coating material was baked. 0.5m width as shown
m, a depth of 0.3 mm, an interval of 1.0 mm, and a shelf board having a coating layer of thickness mm in which a lattice-shaped groove having an area of 56% of the area of the mounting surface of the object to be fired was formed on the surface. .

On the obtained shelf plate, 10 rectangular parallelepiped test pieces of 30 mm × 20 mm × 5 mm which become Mn—Zn ferrite are loaded so that the 30 mm × 20 mm surface is in contact with the shelf plate, and the electric furnace is used to air. 1370 ° C in
, And a baking test was performed in which nitrogen gas was purged at this temperature to maintain an atmosphere with an oxygen partial pressure of 0.1 atm and maintained for 4 hours. When the contact surface of the fired test piece with the shelf plate was observed with a magnifying glass, no coloring, adhesion or the like was found on any of the test pieces as shown in Table 1. or,
Longitudinal direction (3) of the contact surface (lower surface) of the test piece with the shelf
The dimension in the direction of 0 mm) and the dimension in the longitudinal direction of the non-contact surface (upper surface) were measured, and the difference in firing shrinkage was calculated according to the following formula. 2%
Was within the product dimensional tolerance. Firing shrinkage difference = ((contact surface dimension-non-contact surface dimension) / non-contact surface dimension) x 100 (%)

Comparative Example 1 First, a shelf board base similar to that of Embodiment 1 was formed, and a coating material slurry similar to that of Embodiment 1 was rolled on one side of the shelf base for mounting a material to be fired. Was applied. Next, after the moisture in the coating material slurry is sucked into the pores of the shelf board base and the coating material is fixed on the shelf base, drying and baking are performed in the same manner as in Example 1 to a thickness of 0.6 mm. Was obtained. Using the obtained shelf, a firing test was performed on a test piece that became Mn-Zn ferrite in the same manner as in Example 1, and as shown in Tables 1 and 2, the contact surface of the test piece with the shelf was measured. , Overall adhesion is seen,
The difference in firing shrinkage between the longitudinal dimension of the contact surface of the test piece with the shelf plate and the longitudinal dimension of the non-contact surface was 2.0% on average, which was a level that deviated the dimensional tolerance of the product.

Comparative Example 2 First, a shelf board base similar to that of Example 1 was formed, and a large number of parallel slits having a width of 2.0 mm were formed on one side of the shelf board base on which the object to be fired was placed. Polypropylene films (thickness: 0.6 mm) provided at 0.6 mm intervals were laid.
Next, the same coating slurry as in Example 1 was applied to the slits of the film laid on the shelf board base using a roller. Next, the film was removed at the stage where the fluidity of the coating material slurry was lost and the coating material was fixed on the shelf board base as in Example 1. A large number of grooves in one direction were formed in the coating material on the shelf board base in a direction of about 0.6 mm and the interval was about 2.0 mm. Next, drying and baking were performed in the same manner as in Example 1, and as shown in Table 1, the width was 0.6 mm, the depth was 0.3 mm, the interval was 2.0 mm, and the area of the surface of the object to be fired was 23%. A shelf plate having a 0.6 mm-thick covering layer in which a large number of concave grooves in one direction in the area were formed was obtained. Using the obtained shelf, a baking test was performed on a test piece to be Mn-Zn ferrite in the same manner as in Example 1, and as shown in Tables 1 and 2, the contact surface with the test piece shelf was Discoloration, adhesion, and abnormal crystal grain growth are partially observed, and the test piece is in contact with the shelf plate in the longitudinal direction (parallel to the groove direction).
The difference in firing shrinkage between the dimensions of
1.10%.

Examples 2 to 5 and Comparative Examples 3 and 4 The same method as in Example 1 was carried out, except that the same shelf board base and coating material slurry were used, and various polypropylene nets having different wire diameters and intervals were used. Table 1 and Table 2
As shown in Table 2, various kinds of shelves having different widths and intervals of the grooves were obtained. Using each of the obtained shelves, Mn-
When a firing test was performed on a test piece made of Zn ferrite, the reaction resistance of the contact surface of the test piece with the shelf and the difference in firing shrinkage in the longitudinal direction between the contact surface and the non-contact surface were as shown in Table 1, respectively. became.

Example 6 First, a shelf board base similar to that of Example 1 was formed, and a polypropylene mesh (wire diameter 1.5 mm, interval 2.0 mm).
Next, alumina having an average particle size of 1 μm (Al ₂ O ₃ : 99 w
30% by weight of water, and 2.5% by weight of PVA as a binder.
The mixture was mixed for a time to prepare a coating material slurry, and the coating material slurry was applied to a mesh of a net laid on the shelf board base using a roller. Next, after removing the net and drying the coating material in the same manner as in Example 1, the coating was performed by holding at a temperature of 1500 ° C. in the air for 3 hours (elevating and cooling rate: about 200 ° C./hour) in an electric furnace. After baking the wood, Table 1,
As shown in Table 2, the thickness 1 in which a lattice-shaped groove having a width of 1.5 mm, a depth of 0.8 mm, an interval of 2.0 mm, and an area of 67% of the area of the surface on which the object to be fired is formed was formed. A shelf with a coating layer of .2 mm was obtained. Fe-Co is put on the obtained shelf board.
Ten rectangular parallelepiped test pieces of 40 mm × 20 mm × 10 mm formed from alloy powder were loaded so that the surface of 40 mm × 20 mm was in contact with the shelf plate, and the temperature was raised to 500 ° C./hour at 500 ° C. in a nitrogen gas atmosphere by an electric furnace. After the temperature is increased at a temperature rate and maintained for 2 hours, the temperature is raised to 1000 ° C. at a rate of 250 ° C./hour and maintained for 2 hours, and then the temperature is lowered to room temperature. Was done. When the contact surface of the pre-sintered test piece with the shelf plate was observed with a magnifying glass, as shown in Tables 1 and 2, no blistering, cracking, etc. due to discoloration, adhesion, and poor degreasing were not observed.

Comparative Example 5 First, a shelf board base similar to that of Embodiment 1 was formed, and the same coating material slurry as that of Embodiment 6 was applied to one side of the shelf base base on which the object to be fired was placed by a roller. Was applied. Next, after the moisture in the coating material slurry was sucked into the pores of the shelf substrate, and the coating material could be fixed on the shelf substrate, Example 6 was performed.
Drying and baking were performed in the same manner as in the above to obtain a shelf board having a coating layer having a thickness of 1.2 mm. Using the obtained shelf plate, a firing test was conducted in which degreasing and temporary sintering of the test piece were performed in the same manner as in Example 6. When the test piece after the preliminary sintering was observed in the same manner as in Example 6, as shown in Tables 1 and 2, blisters and cracks were generated due to poor degreasing.

In each of the above-described embodiments, the case where the number of the coating layers is one has been described. However, the present invention is not limited to this. A lattice-shaped concave groove may be formed. This is effective when the substrate is susceptible to gaseous phase components. Further, the coating is not limited to the case where the roller is used for applying the coating material slurry to the mesh of the mesh, but may be applied by spraying or other methods. Further, the net is not limited to the one made of polypropylene, and the coating material slurry adheres to the slurry so that the fluidity of the coating material slurry is lost and the coating material is easily removed when the coating material is fixed on the shelf board base. It may be made of polyethylene, silicone, Teflon, stainless steel or the like, which has a low content. Furthermore, not only when removing the net,
If the net is flammable, such as polypropylene or polyethylene, it does not need to be removed because it burns out when the coating is baked. The substrate is not limited to a shelf, but may be a tray, a setter or the like.

[0018]

As described above, according to the jig for firing a functional ceramic component of the present invention and the method for manufacturing the same,
The surface of the coating layer has a fine and uniform uneven structure, the contact area with the object to be fired is small, the support site of the object to be fired is multi-point, and the decomposition gas and evaporation water of the binder from the object to be fired A path with low resistance is secured,
The characteristics of the object to be fired are not deteriorated, and the dimensional accuracy can be remarkably improved.

[Table 1]

[Table 2]

Claims (4)

[Claims] 1. A jig for firing a functional ceramic component having a coating layer made of a material that is hardly reactive with an object to be fired on a surface of the substrate made of ceramics on which the object to be fired is mounted. A jig for firing a functional ceramic component, wherein fine grid-shaped concave grooves having an area of 30 to 80% of the area of the fired object mounting surface are formed. 2. The function according to claim 1, wherein the concave groove has a width of 0.2 to 3.0 mm, a depth of 0.2 to 3.0 mm, and a gap of 0.5 to 2.5 mm. Jig for firing ceramic parts. 3. A mesh of a required mesh is laid on the surface of the substrate made of ceramics on which the material to be fired is placed, and a coating material slurry made of a material which is hardly reactive with the material to be fired is applied to the mesh, and the fluidity of the coating material slurry A method for manufacturing a jig for firing a functional ceramic component, comprising removing a net after drying, drying and firing. 4. A flammable net having a required mesh is laid on the surface of the substrate made of ceramics on which the object to be fired is placed, and a coating material slurry made of a material which is hardly reactive with the object to be fired is applied to the mesh and dried. A method for producing a jig for firing a functional ceramic component, characterized by baking.