JP2006225186A - Firing setter and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manufacture and provide a firing setter with which a body to be fired is fired with high accuracy. <P>SOLUTION: The firing setter used in contact with the body to be fired is manufactured through a sintering process, a placing surface in contact with the body to be fired is a firing surface where mechanical work is not applied and projecting and recessed parts integrated with the base material are formed on the surface of the placing surface. The firing setter has the surface on which the body to be fired is hardly stuck, easily carries a product, is easily recovered and is suitably used for the manufacture of a high precision ceramic component small in the deformation in the firing. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a firing setter and a method for producing the same, and more specifically, precision processing that is suitably used in the firing step of a process for producing fine ceramic materials such as small and precise ceramic parts. The present invention relates to a new fired setter imparting characteristics not found in conventional products and a method for producing the same.

  In the present invention, for example, ceramic electronic parts used in AV equipment, OA equipment, home appliances, and the like are rapidly trending toward miniaturization and precision as electronic equipment becomes smaller and lighter. In order to manufacture products with high dimensional accuracy and quality variations, process control in the manufacturing process is important, and the firing setters used in the past have become small and precise ceramic electronic components. The present invention has been developed in view of the fact that it has not been adequately addressed, and the present invention, for example, in the technical field of fine ceramic products such as ceramic electronic components, is small and precise ceramic parts and high dimensions A new high-precision firing setter is provided for use in the process of manufacturing ceramic parts with high precision and high yield.

  Conventionally, various types of firing setters are known as firing setters for mounting and firing a body to be fired on the surface used in the process of firing ceramic materials, etc., but in these conventional products, The reaction or fusion between the firing setter and the object to be fired has been a problem. In particular, in recent years, there has been a strong demand for reliably solving the problem of reaction and fusion between a fired setter and a body to be fired in a process for producing a small and precise ceramic electronic component by firing. For ceramic electronic parts, such as ceramic capacitors, ceramic piezoelectric materials, microwave dielectrics, high frequency filters, semiconductor capacitors, thermistors, ceramic varistors, ceramic sensors, etc., as raw materials, for example, barium titanate, zirconate titanate Ceramic materials such as lead, strontium titanate, zinc oxide, zirconium oxide, rare earth oxides, or composites thereof are often used.

  In general, these ceramic electronic components are prepared as ceramic fired bodies by preparing and molding raw materials, mounting them on a mounting surface of a firing setter for firing, and firing them at a high temperature in a furnace. It is manufactured by finally assembling it after processing such as forming an electrode. In the process of firing electronic components such as various capacitors and sensors, inexpensive and lightweight oxide-based firing setters such as alumina and mullite are often used. For example, titanium, which is the main raw material of capacitors, is used. Barium oxide barium and lead titanate lead easily react with alumina, which inevitably caused problems such as contamination, deterioration of electrical characteristics, reaction between the setter and the object to be fired or fusion. .

  In recent years, AV equipment, OA equipment, home appliances, etc. have been rapidly reduced in size and weight, and along with this, the downsizing and precision of ceramic electronic parts are being used. Since it is small and precise, it tends to cause contamination of the object to be fired or generation of defective products due to reaction or fusion. These are major problems in producing small and precise parts. Conventionally, a method of preventing reaction or fusion between a firing setter and a body to be fired by spreading ceramic powder that does not react with the body to be fired as a bed powder and firing on the firing setter is employed. However, in this method, since the ceramic powder adheres to the surface of the body to be fired, it is necessary to remove the powder, and when the firing temperature is high, the powders are aggregated and fused, There was a problem that it was difficult to reuse as a flooring powder and it was necessary to treat it as industrial waste.

On the other hand, the proposal which solves the above problems is made | formed by changing the shape and structure of baking setter itself. For example, a porous firing setter (see Patent Document 1) having a large number of air holes having a diameter of 0.2 to 5 mm penetrating the front and back surfaces of the porous ceramic plate has been proposed, but the thickness of the firing setter is thin. There is a problem that the strength becomes weaker and chipping occurs. In addition, the thickness of the firing setter is in the range of 0.5 to 5 mm, a large number of independent depressions are formed on the contact surface with the object to be fired, and the area of one depression is in the range of 0.07 to 36 mm ² A firing setter for firing (see Patent Document 2) has been proposed.

  In addition, as the firing setter having grooves formed on the surface, for example, a groove having a width of 0.2 to 1.5 mm and a depth of 10 to 30% of the thickness of the firing setter is formed to deform the body to be fired. A method for preventing fusion or the like (see Patent Document 3) has been proposed. In addition, as a firing setter having unevenness formed on the surface, for example, an uneven structure having a height of 200 to 1500 μm is formed on the surface of a ceramic substrate in contact with the body to be fired by blasting using a pattern mask, coating treatment, or the like. A fired setter for ceramic firing (see Patent Document 4), and an uneven sheet composed of a material that disappears during firing is interposed, and a green sheet is press-formed to form unevenness on the sheet, By manufacturing a firing setter for transferring the uneven shape (see Patent Document 5), and further printing a ceramic raw material paste using a masking plate having pattern-shaped holes, 0.2 to 2.0 mm A firing setter (see Patent Document 6) made of a plate-like refractory having a convex portion has been proposed.

  However, with these methods or firing setters, it is difficult to form irregularities having a high aspect ratio over a wide area, and to precisely place and provide fine shapes with high precision. Therefore, there has been a demand for the development of a new technology suitable for firing the above precision parts that enables them. In addition, in this type of method, it is necessary to incinerate and remove the uneven sheet used at the time of molding, and because special tools such as patterns are used, etc., from the viewpoint of economic and environmental impact reduction. There was a strong demand for improvement.

JP 2002-265281 A JP 11-79852 A Japanese Patent Laid-Open No. 2004-250241 JP-A-6-281359 JP 11-335179 A JP 2000-109370 A

  Under such circumstances, the present inventors can solve the problems of the prior art in view of the prior art, and, for example, in the manufacture of a small and precise fine ceramic material, We have earnestly researched with the goal of developing a new technology that makes it possible to provide a calcined setter with less deformation, no contamination of the calcined body, and no reaction or fusion with the sintered body. As a result, the mounting surface that comes into contact with the body to be fired is a fired surface that has not been subjected to machining, and the surface of the mounting surface is formed by a firing setter in which an uneven portion integrated with the substrate is formed, The present inventors have found that the above problems can be solved and the intended purpose can be achieved, and the present invention has been completed.

  That is, an object of the present invention is to provide a fired setter suitably used for producing a ceramic fired body with high dimensional accuracy and little quality variation. In addition, the present invention reduces the contact area with the body to be fired and the friction coefficient, prevents the body to be fired from reacting or fusing with the fired setter, has less deformation / warping, and the like. It aims at providing the calcination setter which implement | achieves enabling it to manufacture a baked body. In addition, the present invention makes it possible to form precise unevenness regularly over a wide area by integrally forming the uneven portion on the surface of the firing setter and the main body, and wear resistance due to wear during use. An object of the present invention is to provide a fired setter that imparts properties and enables production of fired bodies with good product yield. Another object of the present invention is to provide a fired setter that is free from contamination and can be easily recovered even when used repeatedly. Furthermore, an object of the present invention is to provide a fired setter that requires high dimensional accuracy, electrical characteristics, and the like, and can be suitably used for manufacturing, for example, small and precise ceramic electronic components. Is.

The present invention for solving the above-described problems comprises the following technical means.
(1) In a firing setter used in contact with a body to be fired, the surface to be mounted that comes into contact with the body to be fired is a fired surface that has not been subjected to machining, and the surface of the mounting surface has a base A fired setter characterized in that a concavo-convex portion integrated with a material is formed.
(2) The firing setter according to the above (1), wherein irregularities having regularity in shape, arrangement, and size are formed on the surface of the mounting surface.
(3) The firing setter according to (1), wherein the uneven portion is a hemispherical, regular square, regular triangle, or regular hexagonal protrusion group formed on the surface.
(4) The firing setter according to (1), wherein the concavo-convex portions are arranged so as to form lattice points of a lattice network.
(5) The firing according to any one of (1) to (4), wherein the size of the uneven portion formed on the mounted surface is 1 mm or less, and the distance between the bottom surfaces of adjacent uneven portions is 0.5 mm or less. Setter.
(6) The firing setter according to any one of (1) to (5), wherein the height of the uneven portion formed on the mounted surface is 0.2 mm or more.
(7) The firing setter according to any one of (1) to (6), wherein the base material of the firing setter is alumina, zirconia, mullite, silicon nitride, silicon carbide, or a composite material thereof.
(8) The firing setter according to (7), wherein the silicon nitride is reaction-sintered silicon nitride.
(9) The firing setter according to any one of (1) to (8), wherein a solid lubricant is disposed on the outermost surface layer of the uneven portion on the surface and is integrally fired.
(10) The firing setter according to (9), wherein the solid lubricant is boron nitride, mica, and / or a monazite structure compound.
(11) The firing setter according to (10), wherein the monazite structure compound is lanthanum phosphate.
(12) A step of slurrying the raw material, a step of injecting the slurry into a porous mold having irregularities on the inner wall surface, and after injection, the porous pores absorb the moisture of the slurry. From the step of solidifying and transferring the irregularities formed on the inner wall surface of the mold to the solidified portion, and the step of taking out the molded body, drying it, firing it at a predetermined temperature, and sintering and densifying it The manufacturing method of the baking setter characterized by becoming.
(13) After the step of transferring the irregularities to the solidified portion, the solid lubricant component is fused with the irregular surface of the molded body as the base material, and then the base material and the solid lubricant are simultaneously sintered and densified. The manufacturing method of the baking setter as described in said (12) which has the process of baking an ingredient integrally.

Next, the present invention will be described in more detail.
In the firing setter of the present invention, the mounting surface that comes into contact with the body to be fired is a firing surface that has not been machined, and an uneven portion integrated with the substrate is formed on the surface of the mounting surface. And, preferably, a large number of fine irregularities whose shape, size, arrangement, and spacing are controlled are regularly formed in a large area on the surface. Thereby, the frictional resistance with the body to be fired is reduced, the flow of the hot gas around the body to be fired in the furnace is adjusted to achieve a uniform temperature distribution, and the surface mounted on the surface. The fired body can be fired with high dimensional accuracy, high purity without being contaminated, and without causing uneven burning due to a temperature difference. In this invention, a to-be-fired body means the target object mounted and baked on a firing setter, and a to-be-mounted surface means the plane part for mounting this target object. The firing setter of the present invention is particularly suitable for use in the firing step in the manufacturing process of small and precise ceramic parts such as precision ceramic electronic parts.

  Concavities and convexities formed on the surface of the firing setter of the present invention, for example, the size and arrangement of the protrusions are basically such that the protrusions controlled to have a fixed shape are uniformly and highly accurate on the surface of the fired body. The shape, arrangement, etc. are not particularly limited as long as they are formed. The irregularities are preferably projections such as hemisphere, quadrangle, triangle, hexagon, etc., for example, hemisphere, cylinder, cone, quadrangular prism, quadrangular pyramid, triangular prism, triangular pyramid, hexagonal prism, six It is possible to select from projections having a shape such as a pyramid. Among them, the projections and depressions in a shape that allows each projection to make point contact with the object to be fired are preferable, for example, a hemisphere, a quadrangular pyramid, a triangular pyramid, and the like are suitable. It is most suitable because it is easy to manufacture and has less damage, wear, etc. during use.

  The protrusions on the surface of the firing setter are preferably arranged regularly, for example, so as to form lattice points of the lattice network, whereby the bottom surface of the object to be fired is more uniform than the protrusions of the firing setter. The heating by the heated gas is homogenized. The size of the bottom of the protrusion is 1 mm or less, preferably 0.4 to 0.8 mm, and the distance between the bottom surfaces of the protrusion is 0.5 mm or less, preferably 0.1 to 0.4 mm. is there. Moreover, the height of the protrusion is 0.2 mm or more, preferably 0.4 to 1.0 mm. If the structure of the protrusions is within this range, the contact surface between the object to be fired and the fired setter is reduced, reacting or fusing, reducing the arrangement and spacing, and based on the heat shrinkage of the object to be fired. It is less likely to cause deformation and warpage, the flow of atmospheric gas in the furnace is controlled, the temperature distribution becomes uniform, and the fired body becomes slippery and easy to recover. can get.

  The firing setter of the present invention is manufactured through a firing process, and the mounting surface that comes into contact with the body to be fired is in a state where no machining is performed. That is, the mounting surface of the fired setter manufactured by firing once consists of a fired surface that is not subjected to machining by a machining means, for example, blasting or cutting. It is not easy to provide regular and uniform fine irregularities on the surface of a ceramic firing setter by mechanical treatment. For example, irregularities and depths formed by blasting have irregular shapes and depths, and are desired. Although it is extremely difficult to form unevenness having a shape and structure, the present invention does not have such a problem.

  In the fired setter of the present invention, the base material and the protrusion are integrated to form an uneven portion. That is, different materials, for example, an adhesive layer is interposed between the fired setter base material and the protrusions, and the two are not joined. For example, the fired setter base material and the protrusions are made of the same material. And integrated by sintering. Thus, by integrating the two, it becomes possible to manufacture a fired setter having excellent friction resistance, strength, heat distribution, thermal conductivity and the like. A fired setter in which the base material and the protrusions are separately manufactured and bonded with an adhesive or the like cannot obtain the excellent characteristics as in the present invention.

  The firing setter of the present invention is manufactured through a firing step, and the firing step is sufficient if the firing setter exhibits sufficient strength, wear resistance, lubricity, and the like by firing. It is determined appropriately according to the material of the raw material. In the firing step, a sintered body can be formed by reaction sintering. For example, a molded body made of silicon is heated to a high temperature in a nitrogen atmosphere to convert silicon into silicon nitride and sinter. However, the firing temperature, time, and the like are appropriately determined according to the material used.

  Examples of the material constituting the fired setter of the present invention include ceramic materials such as alumina, zirconia, mullite, silicon nitride, silicon carbide, silica, zirconia, or composite materials mainly composed of these materials. However, any suitable material can be used as long as it has the same effect as these.

  Since the mounted surface of the firing setter of the present invention has a low surface frictional resistance, even if the fired body is thermally contracted, the fired body is fired without being constrained by the mounted surface of the firing setter, No deformation or distortion occurs in the fired body. Thus, in the present invention, since there is nothing to constrain the thermal contraction of the object to be fired in the firing process, the ceramic material mounted on the fired setter is fired by achieving, for example, a non-defective product yield of 94% or more. can do. In the present invention, it is possible to integrally form a solid lubricant on the outermost surface of the uneven portion on the surface of the firing setter, thereby further reducing the frictional resistance on the surface of the uneven portion. In this case, as the solid lubricant, boron nitride, mica, a compound having a monazite structure, such as lanthanum phosphate, is preferably used. By providing these lubricant layers, the yield of good products can be improved to 100% (see FIG. 3C).

  Next, an example of a method for producing a fired setter according to the present invention will be described. The method for producing a fired setter according to the present invention basically comprises mixing raw material powder made of ceramic powder, an auxiliary agent and the like with water, and slurry. The process of injecting the slurry into the porous mold having irregularities on the inner wall surface, and absorbing the moisture of the slurry into the pores of the porous mold, the raw material powder is attached to the inner wall surface of the mold It consists of a step of solidifying and transferring the irregularities formed on the inner wall surface of the mold to the inking solid part, a step of taking out the molded body from the mold, drying it, firing it at a predetermined temperature, and sintering it. The Further, in the above manufacturing method, the solid lubricant component is sprayed as slurry on the surface of the molded body taken out from the mold, or fused with the uneven surface of the molded body as a base material, dried, and then given At the same time, sintering and densification can be performed, and at the same time, the base material and the solid lubricant component can be sintered together, thereby reducing the surface frictional resistance.

  The raw material slurry for producing the fired setter of the present invention includes, for example, a powder of a heat-resistant substance made of ceramic such as alumina and zirconia, a water-soluble binder such as PVA and an acrylic binder, and a predetermined amount of water. Mixed and made. At this time, the raw material powder preferably has an average particle size of 0.1 to 20 μm, and the particle size is determined by the transfer accuracy of the irregularities formed on the surface of the fired setter after firing, the smoothness of the surface, and the firing. In consideration of cohesiveness and the like, it is appropriately selected from this range.

  The mold for molding the fired setter of the present invention is preferably a porous body, for example, a gypsum mold. In molding using this mold, for example, when a raw material slurry is injected into a mold made of a porous material having irregularities on the inner wall surface, moisture contained in the slurry is absorbed from the porous mold wall surface, The powder adheres to the inner wall surface together with the bonding material and becomes a solid solid. At this time, the concavo-convex shape formed on the inner wall surface of the mold is transferred to the inking solid portion, and a molded body having predetermined concavo-convex is obtained. There is no limitation on the method of forming the predetermined unevenness on the inner wall surface of the mold. Examples of the forming method and the method of cutting the inner surface of the mold to form the recesses. Moreover, the method of producing the sheet | seat and tapes which formed depression in the surface, such as a thermoplastic resin sheet, by press molding, thermoforming, etc., and installing this on the inner wall surface of a type | mold is illustrated. In order to install the sheets in the mold, the sheets must not be displaced or peeled off due to the pressure of the slurry to be injected.

  The molded body taken out from the mold is dried and then fired. In the firing step, the firing conditions are determined according to the characteristics of the used raw material. For example, a raw material mainly composed of silicon nitride powder is sintered by firing at 1800 ° C. In addition, a raw material mainly composed of silicon powder uses a reactive sintering method in which a sintered body is manufactured by sintering at 1800 ° C. after reaction sintering at 1400 ° C. in a nitrogen stream. The reaction-sintered silicon nitride manufacturing method using silicon as a raw material is suitable for manufacturing a fired setter because there is no shrinkage due to sintering and the state at the time of molding can be maintained as it is after sintering. The sintered body produced in this way is formed of a fired setter base and an uneven part, so that it has excellent strength and wear resistance, and its surface has a low frictional resistance. Therefore, it can be suitably used as a firing setter for firing high-quality ceramic parts and the like with high dimensional accuracy.

  In the present invention, it is possible to further improve the yield of non-defective products of the fired ceramic parts by further reducing the surface friction resistance of the fired setter. The frictional resistance can be reduced by forming a lubricant layer made of, for example, boron nitride, mica, or a monazite structure compound on the uneven portion on the surface of the fired setter. For example, the lubricant layer is prepared by applying a powder of lubricant to a slurry with an auxiliary agent such as a binder, and applying it to an uneven surface by coating, spraying, etc., and then firing the formed body on which the lubricant layer is formed. Or it forms by carrying out reaction baking. In addition, the yield of non-defective products can be further improved by forming the lubricant layer (see FIG. 3C). In this way, for example, a fired setter in which irregularities such as hemispheres and a lubricant layer are formed on the surface of the mounting surface is manufactured.

  Various conventional products have been developed in which irregularities are formed on the surface of the firing setter by, for example, blasting, coating, or printing, and the irregularities are formed on the surface of the firing setter by the above processing means. However, due to the limitation of the processing accuracy of these processing means, for example, hemispherical protrusions controlled to a fixed shape are formed uniformly and highly accurately on the surface of the sintered body. It has been difficult to produce a fired setter, and there has been no such product so far, and there has been no fired setter that can be suitably used for the production of miniaturized and refined ceramic parts. It is. On the other hand, the firing setter of the present invention 1) Since the contact area with the body to be fired can be reduced, reaction or fusion with the body to be fired does not occur. 2) The mounting surface of the firing setter Since the material is slippery, deformation and warpage are less likely to occur due to shrinkage when the fired body is fired. 3) The contact area with the fired body is small, and by having a solid lubricating layer, It is easy to transport and collect. 4) Since the base material and the uneven part of the firing setter are integrally formed by the firing process, it is excellent in mechanical strength and wear resistance. Since the gas is heated uniformly by flowing, it has an excellent characteristic not found in conventional products that the atmosphere and temperature distribution are likely to be uniform. The fired setter of the present invention has such characteristics, so that a small and precise ceramic electronic component or the like can be manufactured with high accuracy and high efficiency.

  Furthermore, the present invention provides a firing setter production technique that makes it possible to produce the above-mentioned firing setter in which an uneven portion integrated with the base material is formed on the surface of the mounting surface without performing machining. Is to provide. The method of the present invention makes it possible to form a large number of fine irregularities having a controlled area, shape, size, arrangement, and spacing uniformly and with high accuracy by a simple and efficient method. Thereby, it becomes possible to produce a fired setter having the above-described excellent characteristics.

  According to the present invention, (1) it is possible to manufacture and provide a firing setter useful for firing precision ceramic materials with high dimensional accuracy and little variation in quality. (2) The body to be fired reacts with the firing setter. Alternatively, it is possible to provide a firing setter that is difficult to fuse and that is free from deformation and warpage of the body to be fired due to shrinkage caused by firing. (3) By forming the irregularities on the surface of the firing setter and the substrate together, Can provide a fired setter that secures high mechanical strength and provides resistance to wear and tear due to wear and depression of uneven parts during use. (4) Mount the fired setter on its surface with a slight tilt. (5) A regular uneven portion of the firing setter makes the ambient temperature and product temperature distribution uniform, and (6) a large area of the product. (7) Small and precise ceramic electronic parts such as ceramic capacitors, piezoelectric ceramics, semiconductor ceramics, etc. Can be produced and provided.

  EXAMPLES Next, although this invention is demonstrated concretely based on an Example, this invention is not limited at all by the following Examples.

  In this example, a plate with protrusions in which hemispherical protrusions controlled to have a constant shape were formed on the surface of the sintered body uniformly and with high accuracy was manufactured. Silicon nitride powder having an average particle size of about 1 micron, alumina, and yttria were weighed so as to have a weight ratio of 90: 3: 5, respectively, and 140 wt% of the predetermined amount of PVA and the total weight of the powder. Water was blended and mixed by a ball mill to prepare a raw slurry. On the other hand, a gypsum mold having a hemispherical convex part with a diameter of 0.8 mm formed on the surface and a flat plate with a side of about 60 mm on the inner wall was produced, and the slurry was poured into this mold. After a predetermined time had passed, the molded body was taken out from the mold and further left to improve the green strength. After drying this molded body, it was fired at a maximum of 1800 ° C. in a nitrogen atmosphere of 0.93 MPa to be densified. On the surface of the obtained sintered body, a hemispherical protrusion having a diameter D: 0.7 mm, a distance d: 0.5 mm at the bottom of the protrusion, and a height h: 0.4 mm, controlled to have a fixed shape. However, it confirmed that it was formed in the shape of a regular square lattice uniformly and with high accuracy. FIG. 1 shows a state diagram of the manufactured plate with projections.

  The silicon powder was mixed with 1 wt% of an acrylic binder and 140 wt% of water with respect to the total weight of the powder, and mixed by a ball mill. On the other hand, by the same process as in Example 1, using a gypsum mold having a different size, the diameter D of the protrusion was 0.8 mm, the distance d of the bottom of the protrusion was 0.2 mm, and the height h was 0.5 mm. A plate of the molded body was produced. After drying these molded bodies, they were heated to a maximum of 1400 ° C. in a nitrogen atmosphere and nitrided to produce sintered bodies made of reactively sintered silicon nitride. Produces a plate with protrusions with uniform and high-precision hemispherical protrusions controlled to a fixed shape on the surface of the sintered body with little dimensional shrinkage and warpage during the sintering process. We were able to.

  Zirconia, alumina, and mullite were used as raw material powders, and after molding, as in Example 1, firing was performed in the air to produce a plate with protrusions.

  After forming using silicon carbide as a raw material powder in the same manner as in Example 1, firing was performed in an argon atmosphere to produce a plate with protrusions.

  A slurry containing BN was sprayed onto the surface of the molded body molded in Example 1, dried, and then integrally fired to produce a fired setter. It was confirmed by XRD and observation that a BN layer was formed on the surface of the sintered body.

  In Example 2, a slurry containing BN was sprayed on the surface of the molded body, dried, and then fired integrally to produce a fired setter. It was confirmed by XRD and observation that a BN layer was formed on the surface of the fired body. FIG. 2 shows a fired setter having a solid lubricant layer on the surface of the protrusion formed on the surface of the substrate.

  In Example 3, a slurry containing mica and lanthanum phosphate, which is a monazite compound, was sprayed onto the surface of the molded body, dried, and then fired integrally. It was confirmed by XRD and observation that a layer made of a mixture of lanthanum phosphate / mica was formed on the surface of the sintered body.

(Solid friction coefficient)
In this example, the characteristics of the firing setter of the present invention and the conventional firing setter were compared. The friction coefficient of silicon nitride with respect to the firing setter manufactured in Example 6 and the firing setter (comparative example) made of the same material as in Example 6 and provided with irregularities by shot blasting was measured. As a result, it was found that the fired setter of the present invention has a friction coefficient of about 0.2, which is smaller than the friction coefficient 0.8 of the comparative example (conventional example). This is because the surface contact area with the fired body is small, and the semi-spherical protrusions controlled to a certain shape are formed on the surface of the sintered body uniformly and with high precision. It was inferred that On the surface of the fired setter manufactured in Example 6, a hemispherical protrusion having a diameter D of about 0.8 mm, a distance d between the bottoms of the protrusions of 0.2 mm, and a height h of 0.4 mm is provided. It was formed in a regular square lattice. Further, even in a fired setter without spraying a solid lubricant, the friction coefficient was 0.4, and an effect of reducing the friction coefficient was recognized (see FIG. 3A).

(Transportability)
In this example, a large number of 5 mm square molded body (sintered body) chips were arranged on a firing setter and fired using the firing setters of the present invention and the conventional example. The molded body used was obtained by solidifying granulated powder of silicon, alumina, and yttria in this order at 85: 6: 9 (weight ratio). In the firing step, the reaction was first performed in a nitrogen stream at 1400 ° C. After sintering, it was heated at 1850 ° C. to obtain a sintered body. The molded body was a pipe having an outer diameter of Φ40 mm, an inner diameter of Φ30 mm, and a height of 20 mm, and was a product that required a variation in dimensions after sintering to be within 0.5%. After firing, the sintered setter mounted with the sintered body was tilted at an angle of about 45 degrees and the surface sintered body was slid and conveyed. In the firing setter of the present invention formed on the surface of the surface uniformly and with high accuracy, the sliding was good and all could be recovered. However, in the conventional firing setter, the unevenness height and distribution of the surface were not uniform. As a result, it was found that partial catching occurred and it was difficult to recover the sintered body (see FIG. 3B).

(Good product yield)
In the same manner as in Example 9, a compact shaped body having a height of about 40 mm was fired using the firing setter of the present invention and the conventional example. This molded body was formed by solidifying the above granulated powder. In the firing step, first, reaction sintering was performed in a nitrogen stream at 1400 ° C., and then heated and sintered at 1850 ° C. The molded body was a pipe having an outer diameter of Φ40 mm, an inner diameter of Φ30 mm, and a height of 20 mm, and was a product that required a variation in dimensions after sintering to be within 0.5%. Due to the shrinkage of the molded body due to the firing, in the fired setter of the conventional example, the friction between the fired setter and the molded body is large and restrained at the bottom, so that the sintered body is deformed and warped. On the other hand, the firing setter of the present invention is slippery and has no constraint on the bottom surface, so it shrinks uniformly, hardly deforms or warps, and the dimensional variation is within 0.5%, improving the yield. (See FIG. 3C). This is because when the molded body shrinks during sintering in the firing setter of the present invention in which the hemispherical protrusions controlled to a certain shape are formed uniformly and with high precision on the surface of the sintered body. This is probably because the frictional force with the firing setter is small and the deformation resistance is small, and the gas flow and the accompanying temperature distribution are made uniform by the irregularities provided regularly.

  In this example, a fired setter was manufactured using a mullite raw material. On the surface of the firing setter, a hemispherical protrusion having a diameter D of about 0.8 mm, a distance d between the bottoms of the protrusions of d: 0.15 mm, and a height h of 0.5 mm, controlled to a fixed shape, It was confirmed that it was formed in a regular square lattice shape with uniformity and high precision. 100 compacts of 10 × 10 × 1 mm barium titanate were placed on the firing setter and fired at 1350 ° C. in the atmosphere. About 100 sintered bodies, the degree of deformation was compared with the case of using the firing setter of the conventional example, whereas the standard deviation when using the firing setter of the conventional example was 0.36 It was found that the standard deviation when using the calcining setter of the present invention was improved to 1/3, 0.13. Further, when the firing setter was tilted at about 45 degrees, all the fired bodies could be smoothly conveyed and collected without being caught.

  As described above in detail, the present invention relates to a firing setter and a method for manufacturing the same, and according to the present invention, in a firing setter that is used in contact with a body to be fired, a mounting surface that comes into contact with the body to be fired However, it is a fired surface that has not been subjected to machining, and the surface of the mounting surface is provided with a fired setter in which a concavo-convex portion integrated with a base material is formed, and a method for manufacturing the same. . In addition, the present invention makes it possible to manufacture and provide a fired setter useful for obtaining a fired body with high dimensional accuracy and less variation in quality.

  Conventionally, for example, electronic parts used in AV equipment, OA equipment, home appliances, etc. have been downsized and refined as electronic equipment has become smaller and lighter, and ceramic electronic parts also have high dimensional accuracy and quality. There is a need for small and precise products that do not vary. The present invention, for example, in a firing setter used in the production technology of fine ceramics such as small and precise ceramic electronic components, on the surface of the firing setter, for example, a fine convex portion such as a hemisphere is a large area, It is characterized by being uniformly and regularly formed, thereby reducing the contact area between the firing setter and the body to be fired, reducing the coefficient of friction with the body to be fired, Firing that makes it difficult to adhere the fired body to the fired setter and reduces deformation, warpage, etc. accompanying firing, and imparts resistance to wear due to wear of uneven parts during use. It is possible to provide a setter. Furthermore, the present invention can be used for firing precision ceramic materials that are useful as materials for ceramic electronic components that require high dimensional accuracy, electrical characteristics, etc., such as ceramic capacitors, piezoelectric ceramics, and semiconductor ceramics. It is useful for providing a simple firing setter.

The structure of the baking setter with a protrusion of this invention manufactured by casting molding is shown. The cross-sectional structure of the calcination setter of this invention which distribute | arranged the solid lubricant to the outermost layer is shown. The surface friction coefficient, transportability, and non-defective product yield values of the present invention and the conventional fired setter are compared and shown.

Claims (13)

  In a firing setter that is used in contact with a body to be fired, the mounting surface that comes into contact with the body to be fired is a fired surface that is not machined, and the surface of the mounting surface is integrated with the substrate. A fired setter characterized in that an uneven portion is formed.   The firing setter according to claim 1, wherein irregularities having regularity in shape, arrangement, and size are formed on the surface of the mounting surface.   The firing setter according to claim 1, wherein the uneven portion is a hemispherical, regular square, regular triangular, or regular hexagonal projection group formed on the surface.   The firing setter according to claim 1, wherein the uneven portions are arranged so as to form lattice points of a lattice network.   The firing setter according to any one of claims 1 to 4, wherein the uneven portion formed on the mounting surface has a size of 1 mm or less, and the distance between the bottom surfaces of adjacent uneven portions is 0.5 mm or less.   The firing setter according to any one of claims 1 to 5, wherein the height of the concavo-convex portion formed on the mounting surface is 0.2 mm or more.   The firing setter according to any one of claims 1 to 6, wherein the base material of the firing setter is alumina, zirconia, mullite, silicon nitride, silicon carbide, or a composite material thereof.   The firing setter according to claim 7, wherein the silicon nitride is reactively sintered silicon nitride.   The firing setter according to any one of claims 1 to 8, wherein a solid lubricant is disposed on the outermost surface layer of the concavo-convex portion on the surface and is integrally fired.   The fired setter according to claim 9, wherein the solid lubricant is boron nitride, mica, and / or a monazite structure compound.   The fired setter according to claim 10, wherein the monazite structure compound is lanthanum phosphate.   Slurry the raw material, the step of injecting the slurry into a porous mold having irregularities on the inner wall surface, and after injection, the porous pores absorb the moisture of the slurry to solidify and solidify And transferring the irregularities formed on the inner wall surface of the mold to the solidified portion, and taking out the molded body, drying it, firing it at a predetermined temperature, and sintering and densifying it. A method for producing a calcined setter.   After transferring the unevenness to the solidified part, the solid lubricant component is fused with the uneven surface of the molded body as the base material, and then the base material and solid lubricant component are integrated simultaneously with sintering and densification The manufacturing method of the baking setter of Claim 12 which has the process to bake.

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