JPWO2012014835A1 - Rack for baking - Google Patents

Abstract

This is a firing rack for firing a plurality of stages of an electronic ceramic element by holding a plurality of flat setters in multiple stages in the vertical direction by a setter holding means. The setter holding means is made of any material of Si-SiC containing 0.01 to 30% Si, recrystallized SiC, Si3N4-SiC, and the setter holding means attaches each flat plate-like setter to the outer peripheral side surface. Hold 70 to 100% exposed. Thereby, it becomes a rack for baking excellent in energy efficiency and mass production efficiency, and excellent in the soaking | uniform-heating property of each step | level in multistage baking.

Description

  The present invention mainly relates to a firing rack suitable for multi-stage firing of electronic ceramic elements.

  In general, an electronic ceramic element is obtained by adding a sintering aid and a molding aid to a ceramic fine powder as a main raw material and mixing them, and then forming an unfired element by molding. The unfired element is formed into a ceramic plate called a setter. It is mounted and placed in a firing furnace, and is fired and manufactured while controlling the interior of the furnace at a predetermined temperature and atmospheric conditions.

  The setter is usually used by being stacked in a plurality of stages, and as a structure for forming a space between the setters stacked in a plurality of stages, for example, as shown in FIG. A structure (Patent Document 1) is disclosed in which a flat plate-like setter is stacked on a tray. In addition, a structure is also known in which a peripheral wall portion formed so as to ensure strength enough to withstand stacking is formed on the upper surface periphery of the setter itself to form a dish shape, and this dish-like setter is laminated (Patent Document 2). ).

  However, in the structure in which the setter is completely fitted into the tray as shown in FIG. 9, the outer peripheral side surface of the setter is covered with the tray. Moreover, when stacking the setters, the flow of the gas in the furnace is obstructed by the protrusions 8, and the entire lower surface of the lowermost setter is in contact with the furnace body directly or via a tray. It is difficult to equalize heat at each stage because it is greatly affected by the heat conduction of, for example, an electro-ceramic element that has been heat-treated at the lowermost setter compared to an electro-ceramic element that has been heat-treated at the upper stage. There was a problem that the yield of the product was bad.

  Further, when stacking a plate-like setter around the periphery as in Patent Document 2, the peripheral wall is formed so that the flow of the gas in the furnace is inhibited by the peripheral wall and the strength to withstand the stacking is ensured. There is a problem that the weight and volume that the part occupies with respect to the entire setter hinders high efficiency in energy efficiency and mass production efficiency.

JP 2000-74571 A JP 2009-227527 A

  Accordingly, an object of the present invention is to solve the above-mentioned conventional problems, and to provide a firing rack that is excellent in energy efficiency and mass production efficiency when multi-stage firing of an electronic ceramic element and excellent in heat uniformity of each stage in multi-stage firing. Is to provide.

The firing rack of the present invention made to solve the above-mentioned problems is a firing rack that holds a plurality of flat plate setters in multiple stages in the vertical direction by setter holding means, and the setter holding means has a structure of 0. It is made of any material of Si-SiC containing 01-30% Si, recrystallized SiC, Si ₃ N ₄ -SiC, and the setter holding means sets each flat plate-like setter to 70-100% of its outer peripheral side surface. Is held in an exposed state.

  The invention according to claim 2 is the firing rack according to claim 1, wherein the setter holding means includes a plurality of vertical columns provided with a setter holding mechanism, and a lower end support frame that supports a lower end of the vertical column. A vertical support that has an upper end support frame that supports the upper end of the vertical support, and the setter holding mechanism faces a plurality of recesses or protrusions formed on the inner surface of the vertical support, or a flat setter It is characterized in that it consists of at least one of the beams passed between, the vertical struts as claimed in claim 3, corner vertical struts constituting the vertical sides of the four corners, and You may make it consist of the intermediate | middle vertical support | pillar arrange | positioned perpendicularly between this corner | angular part vertical support | pillar.

  According to a fourth aspect of the present invention, in the firing rack according to the first aspect, the setter holding means comprises a frame-shaped flat plate member having a plurality of stacking protrusions in the peripheral portion, and holds the flat setter. It is characterized in that it is laminated in multiple stages.

  According to a fifth aspect of the present invention, in the firing rack according to the first aspect, the setter holding means includes a pair of linear members arranged to face each other with a plurality of stacking protrusions, and upper portions of the stacking protrusions. It consists of beams spanned between concave surfaces, and is laminated in multiple stages in a state where a flat plate-like setter is held on these beams.

  In addition, when the member which comprises a setter holding means consists of Si-SiC containing 0.01-30% Si, the chemical composition is SiC: 70-99%, Si: 1-30%, It is preferable that SiC + Si is 100% and further contains Al: 0.01 to 0.2%, Fe: 0.01 to 0.2%, and Ca: 0.01 to 0.2%. As described in claim 11, it is preferable that the material of the flat setter is also Si—SiC containing 0.01 to 30% of Si.

  Further, when the member constituting the setter holding means is made of recrystallized SiC, the chemical composition is SiC: 99 to 100%, SiC is set to 100%, Al: 0.01 to 0.2%, Fe: It is preferable to contain 0.01 to 0.2% and Ca: 0.01 to 0.2%.

Also when the members constituting the setter holding means comprises a _Si 3 _N 4 -SiC, the chemical composition _{SiC: 70~80%, Si 3 N} 4: is _{20~30%, SiC + Si 3 N} 4 100 It is preferable to further contain Al: 0.1 to 0.5%, Fe: 0.1 to 0.5%, and Ca: 0.01 to 0.2%.

Firing rack of the present invention, Si-SiC containing 0.01 to 30% Si, recrystallization _SiC, by setter holding means composed of any of the material of the _Si 3 N 4 -SiC, a plurality of plate-shaped The setter is held in a state where 70 to 100% of the outer peripheral side surface is exposed. The setter holding means made of these materials has a higher heat emissivity than the generally used alumina and the like, and 70 to 100% of the outer peripheral side surface of the flat plate setter is exposed. The atmosphere temperature in the furnace can be quickly transmitted to the upper electronic ceramic element. Therefore, it is excellent in the soaking | uniform-heating property of each stage in multistage baking.

  Further, the setter holding means made of these materials has a higher strength under high-temperature conditions than that of generally used alumina or the like, and the size and weight can be reduced accordingly. Therefore, it is excellent in energy efficiency and mass production efficiency when the electronic ceramic element is fired in multiple stages.

  Conventionally, when the setters are stacked in multiple stages while forming spaces between the setters, the weight and volume occupied by the protrusions formed to ensure the strength to withstand the stacking are However, the firing rack according to the invention of claim 2 has a plurality of vertical struts and a lower end support frame that supports the lower end portions of the vertical struts. And a structure including a setter holding mechanism for holding a plurality of flat plate-like setters in multiple stages in the vertical direction, and having an upper end support frame that supports the upper end portion of the vertical column, and ensuring strength that can withstand stacking. Thus, the projecting portion formed as described above becomes unnecessary, and energy efficiency and mass production efficiency can be improved as compared with the conventional case.

  Conventionally, when the setters are stacked in multiple stages while forming spaces between the setters with protrusions, the entire lower surface of the lowermost setter contacts the furnace body directly or via a tray. In order to be greatly affected by the heat conduction from the furnace body, for example, an electronic ceramic element subjected to heat treatment with the lowermost setter has a lower product yield than an electronic ceramic element subjected to heat treatment at the upper stage, etc. In addition, there was a problem that it is difficult to perform soaking at each stage, but according to the rack for firing of the invention of claim 2, a space is also formed between the lower surface of the lowermost setter and the furnace body, While reducing the influence of heat conduction from the furnace body, the setter holding mechanism exposes 70 to 100% of the outer peripheral side surface of each flat plate-like setter from between each vertical column. This makes it difficult for the flow of gas in the furnace, such as the discharge of binder decomposition gas harmful to sintering, to be disturbed, and the heat transfer to the setters that make up each stage becomes more uniform. Can be planned.

  According to invention of Claim 3, a setter can be hold | maintained more stably. Further, in particular, according to the configuration in which the beam is passed between the intermediate vertical columns, heat conduction is performed to the center portion of the setter at each stage through the beam, and therefore, it is affected by the heat conduction from the corner vertical column. It is possible to achieve soaking with the setter edge.

  According to the invention of claim 4, the setter holding means is composed of a frame-like flat plate member provided with a plurality of stacking projections in the peripheral portion, and is configured to be laminated in multiple stages while holding the flat plate setter. The heat capacity of the setter holding means can be reduced to increase the energy efficiency and mass production efficiency when firing the electronic ceramic element in multiple stages. Moreover, it is excellent in the contact property with the gas in a furnace, and is excellent in the soaking | uniform-heating property of each step | level in multistage baking.

  According to the invention described in claim 5, the setter holding means comprises a pair of linear members provided with a plurality of stacking protrusions and arranged opposite to each other, and a beam spanned between the upper concave surfaces of the stacking protrusions. Since the multi-layered structure in which the flat setter is held on these beams is used, the same effect as that of the invention of claim 4 can be obtained.

It is a whole perspective view which shows the rack for baking of 1st Embodiment. It is a perspective view which shows the state which inserted the flat setter in the rack for baking. It is a whole perspective view which shows the modification of 1st Embodiment. It is a graph of the thermal emissivity of Si-SiC which comprises the setter holding means of this invention. It is a whole perspective view which shows the rack for baking of 2nd Embodiment. It is a side view which shows the state which inserted the flat setter in the rack for baking. It is a whole perspective view which shows the rack for baking of 3rd Embodiment. It is a side view which shows the state which inserted the flat setter in the rack for baking. It is explanatory drawing of the state which piled up the conventional setter in the multistage.

(First embodiment)
1 and 2 show a first embodiment of the present invention. The firing rack 1 of the present embodiment has a substantially cubic shape, and the setter holding means includes four corner vertical struts 2 constituting the vertical sides of the four corners, and the four corner vertical struts 2 (2a 2b, 2c, 2d), and a substantially lower-shaped lower end support frame 4 that supports the lower end portions of the four vertical support columns 2, and a substantially lower-shaped upper end support frame 3 that supports the upper end portions of the four vertical columns 2. Yes. As shown in FIG. 1, the firing rack 1 is used by inserting a flat setter 7.

  A horizontal groove portion 21 is formed on the inner side surface of each corner vertical support 2 in parallel to the insertion direction of the flat plate-like setter 7 to constitute a setter holding mechanism. The flat setter 7 is inserted and held at the position of the horizontal groove 21. A plurality of the horizontal groove portions 21 are formed, and by holding a plurality of flat plate-like setters 7 in each horizontal groove portion 21, a multistage firing firing jig as shown in FIG. 2 can be configured. In this way, by constructing a firing jig for multi-stage firing by inserting a flat setter into the rack, compared to the conventional configuration in which the setters are stacked while forming a space at the protruding portion between each setter Therefore, energy efficiency and mass production efficiency can be improved. The form of the setter holding mechanism is not limited to the horizontal groove portion 21. In addition, a plurality of concave portions or convex portions formed on the inner surface of the corner vertical column 2, or a corner vertical column facing each other with a flat setter interposed therebetween You may employ | adopt the shape of the beam etc. which passed between two.

  The firing rack 1 according to the present embodiment includes intermediate vertical struts 5 (5a and 5b) arranged vertically between adjacent corner vertical struts (between 2a and 2b and between 2c and 2d), and a flat setter 7 It is provided in a pair at the facing position across. The pair of intermediate vertical struts (5a and 5b) has a plurality of horizontal hole portions 51 on each inner surface, and a beam 6 is formed between the horizontal hole portions 51 that form a pair at a facing position across the flat plate-like setter 7. Has been passed. The height of the beam 6 is arranged so as to support the central portion of the flat plate-like setter 7 held in each horizontal groove portion 21 from the lower surface. Thereby, since a setter can be hold | maintained more stably, thickness reduction of a setter can be achieved. In addition, since heat conduction is performed to the center of the setter at each stage through the beam, it is possible to achieve a uniform temperature with the edge of the setter that is affected by heat conduction from the corner vertical column 2. it can. However, for example, as shown in FIG. 3, a baking rack 1 that does not include the intermediate vertical column 5 may be used.

  If the outer peripheral side surface length of the flat plate-like setter 4 held in the horizontal groove portion 21 formed on the inner side surface of each corner vertical support 2 is, for example, as shown in FIG. 2, (L1 + L2) × 2, this embodiment Then, the ratio of the outer peripheral side surface covered by the width s of the corner vertical column 2 and the width t of the intermediate vertical column 5 is {(s + t) × 4} / {(L1 + L2) × 2} × 100 = 5-30. %, And 70 to 95% of the outer peripheral side surface of the flat setter 4 has a structure exposed in the firing furnace. Thereby, the favorable in-furnace gas flow can be ensured on the entire setter surface of each stage.

  Further, as in the conventional example shown in FIG. 9, when the setters are stacked in a plurality of stages while forming spaces between the setters with the protrusions 8, the entire lower surface of the lowermost setter is the firing furnace. To contact the furnace body directly or via a tray and be greatly affected by heat conduction from the furnace body, for example, an electroceramic element that has been heat-treated in the lowermost setter has been heat-treated in the upper stage There is a problem that it is difficult to equalize heat at each stage, such as a product yield lower than that of an electronic ceramic element. However, in the present invention, a plurality of corner vertical struts 2 and intermediate vertical struts 5 (hereinafter referred to as vertical struts). A lower end support frame 4 that supports the lower end portion of the vertical column, and an upper end support frame 3 that supports the upper end portion of the vertical column. The setter holding mechanism is provided on the inner surface of the vertical column. Consists of a plurality of horizontal grooves 21 formed By employing the formed space in between the lower surface and the furnace of the lowermost setter is formed, it is possible to reduce the influence of heat conduction from the furnace body.

  From the viewpoint of stably holding the setter even when the firing rack itself is tilted, the lower ends and the upper ends of the vertical support columns 2 and 5 are formed on the lower support frame 4 and the upper support frame 3, respectively. When the entire firing rack is inclined by 30 degrees with respect to the horizontal floor surface by being fitted and fixed to the fitting portion, the inclination angle of the vertical column with respect to the lower end support frame is preferably 2 ° or less. When the inclination angle is 2 ° or more, vibration during use increases, and there is a risk that the secret fired product may be damaged due to vibration accompanying conveyance in the furnace during firing. The problem can be effectively avoided.

  As described above, according to the configuration of the present invention, since the influence of heat conduction from the furnace body of the firing furnace is reduced and a good air flow is ensured, the heat to the setter constituting each stage Transmission becomes more uniform, and soaking can be achieved at each stage.

(Material of setter holding means)
The firing rack of the present invention is usually used under a high temperature condition of about 1300 to 1450 ° C. in an inert gas atmosphere. Therefore, in the present invention, Si-SiC setter holding means contains 0.01 to 30% Si, recrystallization _{SiC, Si} 3 N 4 consisting of any of the material of the -SiC.

  Si-SiC is a material called Si-impregnated SiC in which Si is impregnated between SiC particles. As its chemical composition, SiC is 70 to 99%, Si is 1 to 30%, Al is 0.01 to 0.2%, Fe is 0.1 to 0.2%, and Fe is 0.1 to 0.2% as a trace component (with SiC + Si as 100%). It is preferable to contain 01 to 0.2% and Ca to 0.01 to 0.2%. If the Si content exceeds 30%, the strength and the heat radiation rate are lowered, which is not preferable.

  In addition, the arithmetic average surface roughness is Ra = 0.1-30 μm, the elastic modulus is 200-400 GPa, the strength is 100-400 MPa, the thermal conductivity at room temperature is 150-240 W / m · k, and the porosity is 1%. The following is preferable. By using a material having such a chemical composition and physical properties, it is possible to reduce the weight, increase the strength, and extend the life of the firing rack 1.

  As shown by the solid line in the graph of FIG. 4, the thermal emissivity of the setter holding means made of Si—SiC is 80 to 100% at a wavelength of 8 μm, 20 to 40% at a wavelength of 12 μm, and 60 to 80% at a wavelength of 19 μm. It is preferable that The thermal emissivity can be defined by the chemical composition and the surface roughness. In the present invention, as described above, as the chemical composition, SiC is 70 to 99%, Si is 1 to 30%, and the trace component is external. The composition containing 0.01 to 0.2% Al, 0.01 to 0.2% Fe, and 0.01 to 0.2% Ca is adopted, and the surface roughness is Ra = 0.1. The thermal radiation rate is realized by adopting a configuration of Ra = 10-30 μm, more preferably Ra = 10-30 μm. In addition, the broken line of FIG. 4 is a heat radiation rate at the time of employ | adopting the alumina generally used as a main component of the conventional setter as a chemical composition. As shown in FIG. 4, the heat emissivity of each component (2, 5, 3, 4) is increased by using Si-SiC instead of alumina which is generally used as a main component of a conventional setter. The radiant heat from each constituent member (2, 3, 4) in the furnace is effectively used to enable firing with high energy efficiency.

It is preferable that the surface layer of each constituent member (2, 5, 3, 4) constituting the setter holding means is provided with a coating having a thickness of 1 to 10 μm containing 90% or more of SiO ₂ as a chemical composition. With this coating, reaction deterioration of each component (2, 5, 3, 4) due to the atmospheric gas can be suppressed, and the lifetime of the firing rack can be extended.

In addition to the Si—SiC described above, recrystallized SiC or Si ₃ N ₄ —SiC can also be used. Recrystallized SiC is obtained by fusing and densifying SiC particles by a recrystallization operation, and its chemical composition is SiC: 99 to 100%. However, SiC is 100% and further contains Al: 0.01 to 0.2%, Fe: 0.01 to 0.2%, and Ca: 0.1 to 0.2% as trace components.

Si ₃ N ₄ —SiC is SiC having Si ₃ N ₄ as a bond, and is more suitable for use in a higher temperature region than Si—SiC. Its chemical composition _{SiC: 70~80%, Si 3 N} 4: 20 to 30%, even Al and SiC + _Si 3 _{N 4} as 100%: 0.1~0.5%, Fe: 0.1~0 0.5%, Ca: 0.01-0.2% is contained. These three types of materials are similarly adopted in the second and third embodiments described below.

  The material of the flat setter 7 is not particularly limited, but is preferably the same material as the setter holding means in order to withstand the operating temperature, and in particular Si containing 0.01 to 30% Si. -SiC is preferred. This is because this material has high strength at high temperatures, so that the setter can be thinned. The shape of the flat plate-like setter 7 is not necessarily a flat plate, and may be, for example, a honeycomb shape or a mesh shape. If it is set as these shapes, since the gas in a furnace will flow through the flat plate-shaped setter 7, a more uniform temperature can be achieved. When the firing temperature is relatively low, a mesh made of a heat-resistant metal such as titanium can be used.

(Second Embodiment)
5 and 6 show a second embodiment of the present invention. In the firing rack 1 of the present embodiment, the setter holding means is composed of a frame-shaped flat plate member 10 provided with a plurality of stacking protrusions 11 on the periphery. In the embodiment of FIG. 5, the rectangular flat plate member 10 includes square holes 12 on both the left and right sides, and the flat plate-like setter 7 is placed on this portion. A stacking protrusion 11 protrudes from the center of the side of the flat plate member 10 facing the left and right ends, and a positioning protrusion 13 lower than the stacking protrusion 11 protrudes from a position surrounding the hole 12. ing.

FIG. 6 is a side view showing a state in which the setter holding means holds the flat setter 7 and is laminated in multiple stages, and the flat setter 7 is indicated by a dotted line. Thus, also in this embodiment, 70% or more of the outer peripheral side surface of the flat setter 7 is exposed in the firing furnace. In addition, since the material is any one of Si—SiC, recrystallized SiC, and Si ₃ N ₄ —SiC having a high heat radiation rate, excellent heat uniformity can be ensured as in the first embodiment. Further, since the setter holding means can hold the flat setter 7 and stack them, there is an advantage that the handleability is excellent as compared with the first embodiment.

(Third embodiment)
7 and 8 show a third embodiment of the present invention. In the firing rack 1 of the present embodiment, the setter holding means is spanned between a pair of linear members 16 provided with a plurality of stacking projections 15 and facing each other, and the upper concave surface 17 of each stacking projection 15. The beam 18 is made up of. The stacking protrusion 15 is a mountain-shaped protrusion, and a recess 19 is formed below the protrusion. The beam 18 is a rod-shaped body having a square cross section, and both ends thereof are fitted into the upper concave surface 17 of the stacking projection 15, and the flat plate-like setter 7 is placed thereon.

  FIG. 8 is a side view showing a state in which the flat plate-like setters 7 are held on these beams 18 and stacked in multiple stages, and the flat plate-like setters 7 are indicated by dotted lines. As shown in FIG. 8, the lower concave portion 19 is fitted on the upper side of the beam 18 to stabilize the laminated state.

As shown in FIG. 8, in this embodiment, about 100% of the outer peripheral side surface of the flat setter 7 can be exposed in the firing furnace. In addition, since the material is any one of Si—SiC, recrystallized SiC, and Si ₃ N ₄ —SiC having a high heat radiation rate, excellent heat uniformity can be ensured as in the first embodiment. Since the setter holding means can hold the flat plate-like setter 7 in the third embodiment, it can be stacked, so that there is an advantage that the handleability is excellent as compared with the first embodiment.

  A plate setter of 150 mm × 150 mm × 2 mm was inserted into the baking rack of the present invention to form a baking jig having a 15-layer structure (Example 1), and a setter of 150 mm × 150 mm × 5 mm A ceramic capacitor was fired (1300 ° C., 10 hours) under the same firing conditions using a structure (Comparative Example 1) in which 15 mm protrusions on the periphery were stacked in 15 steps. Table 1 shows the results of examining the product yield at each stage (“Product Yield (%)”), and the results of measuring the temperature difference between the end and the center of the setter constituting each stage (“Setter temperature difference (° C. ) "), The temperature of the center of the uppermost setter and the temperature difference of the center of the setter constituting each stage (" setter central temperature difference (° C) ".

  As shown in Table 1, by using the firing rack of the present invention, it is possible to achieve a uniform temperature at each stage and improve the product yield.

  In order to investigate the influence of the material, the racks for firing according to claim 1 of the present invention were configured with each component ratio shown in Table 2 (Examples 2 to 6, Comparative Examples 2 to 4), and the dimensions were 150 mm × 150 mm × 2 mm. A flat setter was inserted to form a baking jig having a 15-layer structure. Using this, the ceramic capacitor was fired (1300 ° C., 10 hours) under the same firing conditions. Table 2 shows the results of measuring the yield of suspended products as a result of measuring the physical properties (elastic modulus, bending strength, thermal conductivity, porosity, emissivity) of the racks for firing according to Examples 2-6 and Comparative Examples 2-4. As a result, the lifetimes of the firing racks themselves (“lifetime of the multistage shelf assembly (times)”) are shown.

Examples 2, 3, and 4 shown in Table 2 are Si-SiC containing 0.01 to 30% Si, Example 5 is recrystallized SiC, Example 6 is Si ₃ N ₄ -SiC, and Comparative Example 2 is Si-SiC having an excessive Si content, Comparative Example 3 is alumina, and Comparative Example 4 is alumina-silica. As shown in Table 2, configuring Si-SiC containing 0.01 to 30% Si, recrystallization _SiC, the firing rack according to claim 1 in any of the material of the _Si 3 N 4 -SiC Thus, it is possible to improve the product yield and extend the life of the firing rack. On the other hand, when the rack for firing according to claim 1 of the present invention was configured with the members having the chemical compositions of Comparative Examples 2 to 4, a remarkable decrease in shelf life was observed especially as the product yield deteriorated.

DESCRIPTION OF SYMBOLS 1 Rack for baking 2 (2a, 2b, 2c, 2d) corner | angular part vertical support | pillar 21 horizontal groove part 3 upper end support frame 4 lower end support frame 5 (5a and 5b) intermediate | middle vertical support | pillar 51 horizontal hole part 6 beam 7 flat plate setter 8 protrusion Part 10 Flat member 11 Stacking protrusion 12 Square hole 13 Positioning protrusion 15 Stacking protrusion 16 Linear member 17 Upper concave surface 18 Beam 19 Recessed part

Claims (11)

A firing rack that holds a plurality of flat plate-like setters in a multi-stage in the vertical direction by a setter holding means, wherein the setter holding means includes Si-SiC containing 0.01 to 30% Si, recrystallized SiC, It is made of any material of Si ₃ N ₄ —SiC, and the setter holding means holds each flat plate-like setter in a state where 70 to 100% of the outer peripheral side surface is exposed. Rack. The setter holding means has a plurality of vertical columns provided with a setter holding mechanism, a lower end support frame that supports the lower end portion of the vertical column, and an upper end support frame that supports the upper end portion of the vertical column,
The setter holding mechanism is composed of at least one of a plurality of concave portions or convex portions formed on the inner surface of the vertical column, or a beam passed between the vertical columns facing each other across the flat plate-like setter. The firing rack according to claim 1.   3. The rack for firing according to claim 2, wherein the vertical struts are composed of corner vertical struts constituting vertical sides of the four corners, and intermediate vertical struts arranged vertically between the corner vertical struts. .   The setter holding means is composed of a frame-shaped flat plate member having a plurality of stacking projections on the periphery, and is stacked in multiple stages in a state where the flat plate-like setter is held. Rack for baking.   The setter holding means is composed of a pair of linear members provided with a plurality of stacking projections and facing each other, and a beam spanned between the upper concave surfaces of each of the stacking projections. A flat plate is formed on these beams. The rack for firing according to claim 1, wherein the setters are stacked in a multistage manner.   The member which comprises a setter holding means consists of Si-SiC, The chemical composition is SiC: 70-99%, Si: 1-30%, SiC + Si is made into 100%, Furthermore, Al: 0.01-0. It contains 2%, Fe: 0.01-0.2%, Ca: 0.01-0.2%, The rack for baking in any one of Claims 1-4 characterized by the above-mentioned.   The firing of claim 6, wherein the members constituting the setter holding means have a heat radiation rate of 80 to 100% at a wavelength of 8 µm, 20 to 40% at a wavelength of 12 µm, and 60 to 80% at a wavelength of 19 µm. Rack.   The surface roughness according to the arithmetic average of the members constituting the setter holding means is Ra = 0.1 to 30 μm, the elastic modulus is 200 to 400 GPa, the strength is 100 to 400 MPa, and the thermal conductivity at room temperature is 150 to 240 W / m · k. The rack for firing according to claim 6 or 7, wherein the porosity is 1% or less.   The member constituting the setter holding means is made of recrystallized SiC, and its chemical composition is SiC: 99 to 100%, with SiC as 100%, further Al: 0.01 to 0.2%, Fe: 0.01 to The rack for firing according to any one of claims 1 to 4, comprising 0.2% and Ca: 0.01 to 0.2%. The member constituting the setter holding means is made of Si ₃ N ₄ —SiC, and its chemical composition is SiC: 70 to 80%, Si ₃ N ₄ : 20 to 30%, and SiC + Si ₃ N ₄ is taken as 100% and further Al : 0.1-0.5%, Fe: 0.1-0.5%, Ca: 0.01-0.2% is contained, The any one of Claims 1-4 characterized by the above-mentioned. Rack for baking.   The firing rack according to any one of claims 1 to 4, wherein the material of the flat setter is Si-SiC containing 0.01 to 30% Si.

Images