JPH0227925B2 - TSUKISEITAIKYUGATA - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a breathable and durable type. As a method of obtaining finished or semi-finished products such as pottery, ceramic products, plastic products, metal products, rubber products, glass products, etc.
BACKGROUND ART Methods of molding (including casting, hereinafter the same) a liquid, slurry, or softened material using a mold having a cavity have been widely used. It is generally desirable for the mold used in this molding method to satisfy the following requirements, but hitherto there has been no practical mold that can satisfy these various requirements. It must have sufficient mechanical and chemical properties (compressive strength, bending strength, abrasion resistance, corrosion resistance, etc.) to withstand the desired molding process, be able to be used repeatedly as many times as possible, increase the production cycle, and have good surface quality. It has transferability that can handle complex shapes and thin-walled shapes, it is easy to make larger molds and has good dimensional accuracy, it can remove air, gas, water, etc. in the cavity, and the surface of the molded product For example, gypsum molds are used as molds for molding pottery or ceramic bases, and their porosity makes it difficult to form slurry. However, this method is known to absorb moisture from the slip mixture, but this plaster mold has low strength, poor wear resistance, and is prone to chemical reactions with the molding material, so it can be used for several hundred times at most. It has a durability of only a few times, and if forced suction is applied, it can only be used a few dozen times. In addition, the rough skin makes it difficult to clean the molded product, and the low strength makes it unsuitable for larger sizes.Furthermore, when drying a mold that has absorbed water,
The surface becomes calcined gypsum and is prone to peeling, and to avoid this, low temperature drying is performed, so this process takes a long time and reduces the production cycle. Therefore,
Although it is possible to satisfy the condition of , it is not possible to satisfy the condition of . Furthermore, when producing three-dimensional products such as plastic or rubber, fixed molds and movable molds are generally used, and liquid or softened materials are charged into the mold and pressurized at a predetermined pressure. However, since it is not possible to remove the air and air trapped in the material within the cavity, it is difficult to meet the above conditions, resulting in problems such as a decrease in the yield of good products and the need for complicated deburring work. Also, because the mold is made of metal, the following conditions cannot be met. The present invention solves the above-mentioned problems of conventional molding molds, has good strength and abrasion resistance that can withstand multiple uses, as well as good surface quality, corrosion resistance, and dimensional accuracy, and can be used for complex shapes, thin-walled shapes, and It is easy to handle large shapes, and the entire mold is breathable, preventing air, gas, and
The purpose is to provide this kind of breathable and durable type which can effectively remove water and the like and which can be manufactured easily and inexpensively. In order to achieve the above object, the present invention has a composite fired structure made of special materials, that is, non-ferrous metal powder and ceramic powder are used as aggregates, and a silica-based binder containing a liquid component that evaporates is added to the aggregate in a weight mixing ratio. (1 to 5): (1 to 5): 1, or a slurry sample prepared by adding reinforcing fibers to this mixture in an amount of 20% by volume or less, is poured and molded using a model or the actual product, It consists of a composite fired body obtained by drying the molded body and firing it in an oxidizing atmosphere, and the composite fired body has the following characteristics:
At least the outer periphery including the mold surface has a dense hardened layer in which non-ferrous metal oxide is dispersed, and the entire mold has a porosity of 50.
% or less. Embodiments of the present invention will be described below based on the accompanying drawings. FIGS. 1 to 4 show an embodiment of the breathable and durable type according to the present invention, which is composed of a composite fired body 1 made of non-ferrous metal powder and ceramic powder (refractory powder) as aggregates. This composite fired body 1 has a dense hardened layer 2 at least on the outer peripheral portion including the mold surface 11.
In the embodiment shown in FIG. 2, the hardened layer 2 extends to the center, but a backing layer 3 made of an unfired mixed structure may be provided inside the hardened layer 2 as shown in FIG. Figures 1 and 2 show an embodiment of a split mold, in which a passage 12 leading to the mold surface 11 is made of a hardened layer, and a conduit 27 for feeding the molding material is attached to the passage 12. . Depending on the application, holes for pins may be formed through the hardening layer and the backing layer, and if necessary, conduits and heaters for mold cooling and heat retention may be embedded. FIGS. 3 and 4 show another embodiment of the present invention, which consists of a composite fired body 1 made of nonferrous metal powder, ceramic powder (refractory powder), and reinforcing fibers 4 as aggregates. Similar to the previous embodiment, the composite fired body 1 shown in FIG. Reinforcing fibers 4 are almost uniformly dispersed within each layer of 3 and at the boundary between both layers, and these dispersed reinforcing fibers 4 strengthen the unfired mixed structure constituting the backing layer 3,
Furthermore, by being passed between the hardened layer 2 and the backing layer 3, the adhesion between both layers is enhanced. In the embodiment shown in FIG. 4, the entire mold consists of a hardened layer 2,
Reinforcing fibers 4 are dispersed throughout this layer. The hardened layer 2 consists of a bonding structure of oxide particles 20 of nonferrous metal powder dispersed in ceramic powder and fired ceramic particles 21, as shown in FIG. 5a. Although the formation mechanism of this hardened layer 2 is not necessarily clear, it is generally considered to be the result of oxidation of non-ferrous metal powder and diffusion bonding at the interface with ceramic particles. This hardened layer 2 has fine pores 22 (about 5 to 20 μm) caused by the evaporated components in the silica-based binder passing from the inside of the hardened layer to the outside and disappearing during the drying and firing steps. have,
These fine pores 22 form a porous yet dense and smooth surface. On the other hand, the inner backing layer 3 of the hardened layer 2
As shown in Figure b, it consists of a mixed structure of unfired non-ferrous metal powder 20' and ceramic powder 21', and the interface between these non-ferrous metal powder 20' contains silica-based particles as mentioned earlier. Coarse pores 22' are formed due to the disappearance of the evaporated components in the binder. These pores 22' communicate with the pores 22 of the hardened layer 2, so that the entire composite fired body 1 has a porous ventilation structure. The pores 22, 22' are characterized in that they are not cracks. Although the porosity depends on the composition and firing conditions described below, it is generally in the range of 1 to 50%, and has a compressive strength of about 200 to 900 Kg/cm ² or more. Therefore, in the breathable durable type of the present invention as shown in FIGS. 1 to 4, aggregate and caking material are mixed and kneaded to obtain a slurry sample, and this slurry sample is poured and molded. step, a step of drying the mixed molded body, and a step of firing the product through this step under oxidizing atmosphere conditions. First, the step of obtaining a slurry sample is to sufficiently stir and mix nonferrous metal powder and ceramic powder or reinforcing fibers, and then add one or more types of silica-based binder containing a liquid component that evaporates. and thoroughly mix and stir. Here, the ``silica-based binder containing an evaporable liquid component'' is used to bond non-ferrous metal powder particles and ceramic powder particles, and the liquid component evaporates during the drying or firing process, forming the material from within the structure. This is to obtain air permeability by forming pores consisting of fine open pores by passing through the body or the outside of the fired body. Colloidal silica is a typical example of a silica-based binder containing this evaporable liquid component. Colloidal silica is a stabilized colloidal solution of silica SiO ₂ using water as a dispersion medium. In this case, the evaporated component is water, and pores are formed by the evaporation of water. Furthermore, examples of the silica-based binder containing a liquid component that evaporates include ethyl silicate, that is, alcohol-based solvent-based silica gel. This uses an alcoholic solvent such as methanol or ethanol as a dispersion medium, and the evaporated component is an alcoholic solvent such as methanol or ethanol. Next, as the "non-ferrous metal powder", nickel powder, chromium powder, manganese powder, molybdenum powder, titanium powder, copper powder, cobalt powder, tungsten powder, etc. are mainly used. Each of these may be used as a single powder, a mixed powder of two or more kinds, an alloy powder, or a composite powder. If necessary, non-ferrous metal powders other than those mentioned above, such as zinc powder, tin powder, lead powder, etc., can also be used, but properties such as strength and heat resistance will deteriorate. The inventors of the present invention made a similar attempt using iron-based powder such as cast iron powder, but a slag-like substance that melts at low temperatures was generated and the surface quality deteriorated, making it impossible to use it as a mold. We found that there are restrictions. In addition, the chemical stability of the oxide is poor, and there is a risk that rust may adhere to the surface of molded products, which poses a major problem in molding ceramic bases and plastics.
On the other hand, non-ferrous metal powders, if appropriately selected, can overcome the problems associated with iron-based powders and exhibit excellent properties. That is, it has high strength, improved heat resistance and corrosion resistance, improved dimensional accuracy and surface texture, good hue, and high commercial value. Examples of "ceramic powder" include neutral types such as mullite, calcined alumina, activated alumina, fused alumina, chromite, and sillimanite, and acidic types such as fused silica, zirconium, and fused zircon. Although generally suitable, basic materials such as magnesia, talc, etc. can also be used. Furthermore, as the "reinforcing fiber", steel-based fibers are generally applicable. In particular, since stainless steel fibers do not corrode during the firing process, they have a high reinforcing effect on both the hardened layer and the backing layer. Other reinforcing fibers, such as ordinary steel fibers,
Reinforcing effects can also be obtained by using ceramic fibers such as glass fibers and alumina fibers, carbon fibers, etc., and the advantages of preventing cracks and preventing ceramic powder from falling off can also be obtained. For example, glass fiber has good adhesion with silica-based binders, so it can be expected to have a great reinforcing effect, and is useful in cases where iron oxides are extremely objectionable. The blending ratio of the nonferrous metal powder, ceramic powder, and silica-based binder is approximately (1-5):(1-5) by weight.
5):1 is preferable, and various properties such as strength, air permeability, thermal conductivity, and surface texture can be obtained in a well-balanced manner by this blending ratio. Here, the lower limit of the mixing ratio was specified because it is necessary to obtain the minimum strength that can be used as a mold, and the upper limit was specified because if there is too much aggregate, the moldability will deteriorate. This is because it reduces the covering ability of the silica-based binder, resulting in a decrease in strength and deterioration in the stability of the mold surface. The reason for setting the upper limit for non-ferrous metal powder is that even if the blend of ceramic powder and silica-based binder is appropriate, if the non-ferrous metal powder is in excess, sufficient strength will not be obtained, and the surface quality will deteriorate. This is because transferability is impaired. The reason why the upper limit of ceramic powder is limited is that the strength will be impaired if excessively blended. The silica-based binder is necessary for bonding aggregates and for providing air permeability. If the silica-based binder is also excessively blended, the strength will decrease due to excessive porosity. When reinforcing fibers are used together, the amount added is approximately 1
It should be ~20vol%. If it is less than 1%, effects such as improved strength and dimensional stability cannot be expected. However, addition of more than 20 vol% tends to cause fiber balls, which reduces moldability. Further, excessive precipitation on the surface of the hardened layer deteriorates the skin and is also disadvantageous in terms of cost. In addition, the particle size of non-ferrous metal powder is generally 2 in the maximum dimension.
~500μm, ceramic powder is 10~300μm in maximum dimension
m is desirable. The lower limit was specified because, although from the standpoint of transferability and surface roughness of the mold surface, the smaller the particle size, the better, but on the other hand, cracks are more likely to occur. The upper limit was specified because of the need for strength and because excessive porosity would deteriorate the surface properties of the mold. The reinforcing fiber varies depending on the size of the mold etc.
For example, a material having a length of 0.5 to 30 mm and a thickness of 5 to 400 μm may be appropriately selected. Next, the slurry sample is solidified and molded into a desired shape. This is done, for example, by pouring a slurry sample into a mold set with a model, actual object, master model, etc., and leaving it for a required period of time. During this pouring, it is also effective to add a hardening agent, apply vibration to promote filling properties, or squeeze. When using a mold with a conduit or a guide, this can be easily carried out by inserting bottles or pipes into the mold during pour molding. Next, in the present invention, after the molded product obtained in the previous step is removed from the mold, it is subjected to natural drying and/or ignition drying. This is to prevent the generation of cracks and distortion, as well as to make the silica-based binder more porous by evaporating the alcohol and water contained in it; the former is naturally dried for 1 to 48 hours. Select from a range such as: Further, in order to accelerate drying, a high temperature atmosphere, hot air, etc. can also be used. The latter ignition drying may be performed by directly igniting the molded body with a torch lamp or the like. The molded product after this drying process has air permeability throughout and can be used as it is for pressureless casting. However, the mechanical strength is low and durability is unavoidably lowered, so in the present invention, the molded body after the drying process is fired in an oxidizing atmosphere. The oxidizing atmosphere may be air or may be so-called oxygen-enriched air in consideration of oxygen supply. The firing conditions depend on the nonferrous metal powder type, blending ratio, mold dimensions, intended porosity, etc., but generally the firing temperature should be 600 to 1500°C and the firing time should be at least 1 hour. The lower limit of firing temperature is 600℃, the lower limit of firing time is 1
The reason why the time is set is because the firing is insufficient and a dense hardened layer, which is a feature of the present invention, is not formed, and the strength necessary for a durable type cannot be obtained. The reason why the upper limit of the firing temperature was set at 1500°C is that although a hardened layer is formed, dimensional accuracy decreases, the surface becomes rough, and transferability deteriorates. The longer the firing time, the higher the strength, but there is a risk of roughening the surface and reducing productivity. Although it depends on the mold dimensions, etc., the maximum time should be 50 hours. This firing process in an oxidizing atmosphere progresses the firing of the ceramic powder and the oxidative firing of the non-ferrous metal powder dispersed in the molded body, and a dense hardened layer is gradually generated from the surface to the inside. At the same time, the evaporated components of the silica-based binder remaining in the molded body are removed, promoting porosity, and upon completion of firing, the composite fired body 1 as shown in Figures 1 to 4 has an air permeable property. A mold is obtained. In addition, in the present invention, in order to adjust the air permeability (porosity), the type of nonferrous metal powder and ceramic powder,
The particle size, the blending ratio of nonferrous metal powder, ceramic powder, and silica-based binder, vibration and squeezing conditions during pour molding, firing conditions, etc. may be arbitrarily set while taking into consideration the required strength and the like. Figure 6 shows silica-based binder: aggregate (non-ferrous metal powder +
It shows the relationship between the blending ratio of ceramic powder) and the porosity, and it can be seen that the porosity tends to increase as the blending ratio of the silica-based binder increases. Next, the usage situation and operation of the present invention will be explained. Figures 7 to 9 show examples of the use of the breathable mold according to the present invention, and Figures 7a and 7b show how the mold of the present invention is used as a slip casting mold for molding ceramic base material, and slurry-like material is (Slip) A device in which water is discharged by pressurized injection of W.
Figures 8a to 8d show an example of application to a plastic blow mold. FIG. 9 shows a method applied to forming liquid or slurry materials W such as molten metals such as aluminum alloy steel, copper, and iron, mortar, wax, and refractories using a non-pressure suction method. In FIG. 7a, the composite firing is divided into a fixed mold 1a and a movable mold 1b, and a slurry-like material W is injected under a predetermined pouring pressure into a cavity 10 constituted by these two molds. Due to this pressure, the air in the cavity 10 is expelled to the outside through the pores of the composite fired body, and then the water contained in the slurry-like material W is expelled through the pores, and after a certain period of time, the movable mold 1b is opened and molded. Goods
W ₁ is taken out. In addition, in this process,
Prior to or concurrently with the injection of the slurry material W, a suction force may be applied from outside the mold as in FIG. 9. In FIG. 8a, the composite fired body is a movable mold 1b,
1b, the molding material (parison) W' is heated and softened in advance, and is inserted into the movable molds 1b, 1b while being given a primary bulge by the air blowing pipe 31 of the die 30. The mold is then clamped as shown in FIG. 8b, and the molding material W' is confined in the cavity 10. Then, as shown in FIG. 8c, air is injected into the molding material W' by the air blowing pipe 31, which causes the molding material W' to expand, and this pressure causes the air in the cavity 10 to blow into the hardened layer and backing layer. The molding material W' is discharged to the outside through the pores and comes into close contact with the mold surfaces 11, 11.
Then, as shown in Fig. 8d, the die 30 is released,
By holding for a predetermined time, the molding material is cooled and becomes a molded product. In the above process, the movable molds 1b, 1b are
The suction force may be applied from outside. Molding by the non-pressure suction method shown in FIG. 9, for example, is divided into a fixed mold 1a and a movable mold 1b,
A mold coating agent and mold release agent are applied to mold parts 1 and 11, and the material is injected and mold released by incorporating it into a molding device. The suction parts 8, 8 are connected to a pressure reducing device 9 such as a vacuum pump via a hose or the like, and a suction force is applied during injection of the material W and/or during molding. Although not shown, the mold according to the present invention can also be applied to molding using a low pressure suction method. That is, in this case, a fixed mold and a movable mold made of a composite fired body are used instead of the mold in the known vacuum casting apparatus, and suction parts are provided at desired locations on the fixed mold and the movable mold.
These suction parts may be connected to a pressure reducing device as in the case of FIG. 9, and the piston rod of the mold opening/closing cylinder may be connected to the movable mold. During molding, a liquid or slurry material is placed in a crucible-shaped container, and gas is pressurized through the air hole provided in the airtight lid on the crucible-shaped container to form fixed and movable cavities through conduits. The material is pushed up, and at the same time a suction force is applied through a suction section by a pressure reducing device. Furthermore, when forming a soft lumpy material with plastic flow, the composite fired body of the present invention is used in place of the male mold made of conventional metal molds, and a fixed mold corresponding to the female mold is fixed to the press bed side. Then, attach the movable mold corresponding to the male mold to the press slide side,
A suction section may be provided at a desired location of both types and connected to a decompression device. During molding, the material is filled into the mold surface of a fixed mold, and then the movable mold is operated to apply the necessary pressure to the material while sucking air through the suction section. The present invention can also be used as a mold for vacuum forming plastic sheets. In each of the above-mentioned moldings, according to the present invention, the mold is composed of a composite fired body 1 made of non-ferrous metal powder and ceramic powder as aggregates, and this composite fired body 1 is made of a dense hardened layer of oxidized non-ferrous metal powder. 2 forms the outer circumferential surface including the mold surface 11, the mold strength is as high as at least 200 kg/cm ² or more, and it also has the necessary conditions for durability such as good abrasion resistance and heat resistance. Therefore, no cracking, chipping, or crumbling will occur even after repeated rapid heating and cooling, repeated mold clamping pressure, etc., and no chipping at important corners of the mold will occur. In addition, since it has good corrosion resistance and is chemically stable, it does not alter the quality of molded products or cause deterioration in quality. Therefore, when used, for example, in a mold for slip casting, the service life can be dramatically increased. When aggregate and reinforcing fibers are used together, the bending strength is high,
A feature of little dimensional change can be obtained. Furthermore, in addition to having good properties as a durable type, the hardened layer 2 constituting the composite fired body 1,
Alternatively, this and the inner backing layer 3 are made of porous material consisting of fine pores 22, 22', and the ventilation locations are not limited as in the case of a mold.
The entire mold has good ventilation. Furthermore, although the hardened layer 2 constituting the mold surface has suction holes, it is dense, and there is no deterioration in surface quality, which was a problem with iron-based powder, and the surface roughness is small. . Therefore, since it is made by pour molding, it has good transferability and mold reproducibility. Therefore, by applying suction or pressure from a desired location during the molding process as shown in Figures 7a to 9, the entire cavity or mold surface can be uniformly made negative or positive. This makes it possible to evenly fill the material to every corner of the cavity or mold surface and provide good transferability, while at the same time eliminating air inside the cavity, air drawn in during material filling, and gas and water released from the material. Can be eliminated quickly and reliably. Furthermore, the mold of the present invention has a lower thermal conductivity than a metal mold, and when used for casting, etc., the molten metal flows well even when the molten metal flows in at a low velocity and low pressure. For these reasons, molded products with complex shapes and thin shapes without pinholes or cavities on the surface or inside can be molded very easily. In addition, the suction parts 8, 8 in the above embodiment may be obtained by inserting the intake pipe into the mold during casting molding, or may be provided after firing. For the outer surface other than the suction part, methods such as applying a sealing material as appropriate, attaching it to an airtight sequence, or joining a planar body may be used. Of course, the entire mold can also be used as a suction section by attaching a porous frame 28 as shown in FIGS. 8a to 8d. In the above embodiment, both of the split molds are composed of composite fired bodies, and each mold is inhaled, but in some cases, only one of the divided molds is made of a composite fired body, or even if only one side is inhaled. good. Next, specific examples of the present invention will be shown. Example A breathable mold according to the present invention was experimentally produced. The material specifications of the prototype mold are shown in Table 1 below.

【table】

[Table] A slurry sample was obtained by uniformly mixing and stirring the above A to G, and each was poured into a mold containing a master model (Western tableware, sanitary ware, container, sewing machine parts). A molded body was obtained. After demolding the solidified molded bodies, A to C were dried with hot air for 3 hours, D to G were dried by direct ignition for 0.5 hours, and fired under air conditions at a firing temperature in the range of 900°C to 1500°C. A breathable mold was obtained. Figure 10 shows the relationship between firing time and compressive strength at a constant firing temperature (1100°C) for breathable types A, D, E, and F, and for breathable types A and B at a constant firing time. The relationship between compressive strength and firing temperature under the conditions of (6 hours) is as follows:
As shown in Figure 1. From these results, it can be seen that the breathable mold of the present invention has high compressive strength, and the strength increases as the firing time or temperature increases. Baking time is constant for breathable types C and G (6
Figure 12 shows the relationship between the firing temperature and bending strength (time), and Figure 13 shows the relationship between the amount of fiber mixed in and the dimensional change. From these results, it can be seen that when reinforcing fibers are added, the bending strength is significantly improved and changes in mold dimensions are suppressed. Furthermore, it can be seen that the dimensional accuracy is good even when no additives are used, and is significantly better than the approximately 1.6% when manufactured under the same conditions using cast iron powder as the metal powder. Figure 14 shows the results of examining the relationship between firing time, hardened layer thickness, and porosity (apparent porosity) under conditions of a constant firing temperature (1000°C) for breathable types A to G. . In the case of the present invention, it can be seen that the entire mold has a porosity of at least 20% or more. Note that if the mold size is small, the hardened layer will extend to the center, but it was confirmed that a minimum porosity of 20% can be maintained. Using breathable type C with a porosity of 35%, Figure 7a,
A slip casting durability test was conducted on the dinner wear shown in Figure 7b. Slips are made of carillon, clay, or clay commonly used for sanitary ware.
A mixture of appropriate amounts of quartz, feldspar, chinastone, cervene, and limestone was poured into the cavity through a conduit at a pressure of 10 kg/cm ² to obtain a thickness of 10 to 12 mm at a deposition rate of 10 minutes. As a result, the suction mold according to the present invention can be used more than 20,000 times to produce a molded product with an accurate shape. Similar durability was obtained even when reduced-pressure casting was performed by applying force, and the molded product was extremely dense and had no pores. In the case of conventional plaster molds, the limit of natural water absorption is at most 300 times, but when combined with suction power,
Since the upper limit is about 80 times, it can be seen that the present invention can dramatically improve durability. This is because, in the case of the present invention, despite its air permeability, it has high mechanical strength, good abrasion resistance, and is not affected by thermal changes caused by rapid heating and cooling. Using air-permeable mold D having a porosity of 38%, a plastic product (automobile headrest) shown in FIGS. 8a to 8d was blow molded. The molding material used was soft vinyl chloride, parison thickness 2.5 mm, and the blowing pressure was 3 Kg/cm ² . We also adopted a method of applying a suction force of 700 mmHg after mold clamping and before air blowing. The results of measuring the surface roughness of the molded product and mold in this case are shown in Figure 15.
It can be seen that excellent transferability was obtained.
This is due to the fact that, in addition to being a pour molding process, the mold surface is dense and has good air permeability throughout the entire mold surface. The remaining air in the aged cavity and the resulting deterioration in transfer performance have been successfully resolved, making it highly practical. Similar results were also obtained when the above-mentioned mold was used as a plastic vacuum molding mold to mold a grained sheet. Using breathable type E with a porosity of 35%, pure copper products (thickness 1.3 mm x 20 mm) are gravity cast.
mmHg suction was performed. The casting conditions are: casting temperature 950℃, casting time 3~5sec, mold release time 15~
It took 50 seconds. As a result, there is no sinkage and the casting surface is extremely good.
A high-quality pure copper casting with no cavities on the surface or inside was obtained. No damage to the mold was observed even after 150 uses. According to the first invention of the present invention explained above,
It has high mechanical strength, excellent abrasion resistance and heat resistance, and has good air permeability and water absorption throughout the mold, as well as good surface texture and good corrosion resistance, which prevents quality deterioration and quality deterioration of molded products. Therefore, it is possible to easily and inexpensively manufacture molds for large, complex, and thin-walled molded products. According to the second aspect of the present invention, in addition to the above, it is possible to provide this type of breathable mold which has even higher strength, good dimensional stability, and high durability. The present invention is suitable as a water absorption mold for ceramic products such as ceramics, and can also be applied as a mold for various liquid, slurry, soft block, and film materials such as plastic products, rubber products, glass products, and metal products. It is possible.

[Brief explanation of drawings]

1 to 4 are cross-sectional views illustrating embodiments of durable breathable types according to the present invention, and FIGS. 5a and 5.
Figure b is a cross-sectional view schematically showing the structure of the mold of the present invention;
FIG. 6 is a graph showing the relationship between aggregate blending ratio and porosity in the present invention, and FIGS. 7a and 7b are usage state diagrams when the present invention is used for molding ceramic bases.
Figures 8a to 8d are usage state diagrams when the present invention is applied to plastic blow molding, Figure 9 is a usage diagram when the present invention is applied to vacuum molding, and Figure 10 is a usage state diagram when the present invention is applied to blow molding of plastics. A graph showing the relationship between time and compressive strength, Figure 11 is a graph showing the relationship between compressive strength and firing temperature, Figure 12 is a graph showing the relationship between firing temperature and bending strength, and Figure 13 is a graph showing the relationship between fiber content and dimensional change. FIG. 14 is a graph showing the relationship between firing time, hardened layer thickness, and porosity. FIG. 15 is a graph showing the surface roughness measurement results of the mold and molded product. 1, 1'... Composite firing mold, 2... Hardened layer, 4...
...Reinforcement fiber.

Claims (1)

[Scope of Claims] 1 Non-ferrous metal powder and ceramic powder are used as aggregates, and a silica-based binder containing an evaporable liquid component is mixed in the weight ratio of (1 to 5): (1 to 5): 1. A composite fired body is obtained by pouring and molding a slurry-like sample, drying the molded body, and firing it in an oxidizing atmosphere. A breathable and durable type with a porous structure with a porosity of 50% or less. 2 Non-ferrous metal powder and ceramic powder are used as aggregates, and a silica-based binder containing a liquid component that evaporates is mixed in a weight ratio of (1 to 5): (1 to 5): 1, and reinforcing fibers are further added to 20 A composite fired body is obtained by pouring and molding a slurry sample mixed at a volume percent or less, drying the molded body, and firing it in an oxidizing atmosphere. A breathable and durable type that has a hardened layer and the entire mold has a porous structure with a porosity of 50% or less.