JPH0351667B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a conductive zirconia-based sintered material that has high toughness and hardness, has excellent corrosion and wear resistance, and can be used for multiple purposes by imparting conductivity to zirconia, which is originally an insulating material at room temperature, and a method for producing the same. It is something. In recent years, zirconia (hereinafter referred to as ZrO ₂ )-based materials have become
Since the development of partially stabilized ZrO ₂ sintered material using Y ₂ O ₃ , attempts have been made to use it for structural members and tool materials such as cutting tools that require high strength. However, although these stabilized ZrO ₂ (including partially stabilized materials, the same applies hereafter) have high strength, their hardness is at most about H _R A90, which is inferior to Al ₂ O ₃ -based materials, so they were not used as cutting tool materials. In many cases, it cannot be put to practical use due to its wear resistance. Furthermore, stabilized ZrO ₂ is characterized by low thermal conductivity and high coefficient of thermal expansion, which may be advantageous in some applications, but on the other hand, it has insufficient properties in terms of thermal shock resistance. Next, the stabilized ZrO ₂ sintered body is a white material and has the disadvantage that it cannot be used as a material for decorative parts in black colors. Furthermore, stabilized ZrO ₂ is used as a heater material in high temperature ranges, but in low temperature ranges, the specific resistance value is very high and it belongs to insulating materials, so it has the disadvantage that it cannot be used as a self-heating element. _ZrO2
The grinding process is inferior to other ceramic materials,
In addition, when drilling holes or processing into complex shapes, since the material is an insulating material, electric discharge machining, which has a high machining rate, cannot be used, and ultrasonic machining must be relied upon. In order to eliminate the drawbacks of stabilized ZrO ₂ mentioned above, the material of the present invention has high toughness and hardness, excellent corrosion and wear resistance, and improved thermal shock resistance by adding a carbide component and imparting conductivity. The aim is to obtain a ZrO _2- unit sintered material that can be processed into self-heating heater materials and other products for various uses by electrical discharge machining, and which can significantly reduce processing costs. The features constituting the present invention will be described in detail below. Firstly, materials for watch parts, bracelets, tie pins, cufflinks, pendants, and other decorative parts need to maintain a glossy surface with a beautiful appearance for a long period of time.
It is required to have high corrosion resistance and breakage resistance, and it is also required for high efficiency machining to have grinding workability in the product manufacturing process and electric discharge machinability for forming complex shapes or drilling holes. Furthermore, among the characteristics required of these various decorative members, it is natural that the most important requirement in terms of product reliability is to have sufficient impact resistance to prevent damage to expensive products. The fact that the decorative member is not too heavy is also required as a desirable characteristic when used as an accessory. Conventionally, cemented carbide tool materials, cermet materials, stellite, etc. have been used as materials for decorative parts that require the above characteristics, but although they have excellent strength, they are often heavy and Since all of these materials contain metal components, they have a metallic luster, and it has been impossible to obtain black materials. On the other hand, various types of ceramic materials that do not contain metal can be found as colored decorative members with beautiful colors, but since these types of materials do not have electrical conductivity, they require a large number of processing steps when creating complex shapes or holes. Another drawback was that the strength was generally low, resulting in poor breakage resistance. ZrO ₂ stabilized (including partial stabilization) with Y ₂ O ₃ etc. has been reported as a strong ceramic material, but its grindability is very poor.
Moreover, it is a white material and has little utility value as a decorative member. Secondly, metal-based materials are generally mainly used as resistance heating elements (heater materials), and ceramic resistance heating elements include insulating ceramic materials with conductive heating paths bonded to them, or those with heating elements embedded in them. Other SiC-based heating elements and ZrO ₂ -based heating elements are used for high temperature applications. Among the various heating elements mentioned above, metal materials are inferior in terms of corrosion resistance, oxidation resistance, and wear resistance, so they tend to be immersed in oxidizing atmospheres, acids, alkaline substances, salt, etc., and their low hardness causes friction. As a heating element used under such conditions, wear may shorten the lifespan, and SiC heating elements have low strength and may cause breakage.Also, the constituent crystal grains are coarse and the structure is not dense, so they are used under friction conditions. In this case, a smooth surface cannot be obtained, and there are drawbacks such as particle shedding, wear, and damage to the mating material. In addition, ZrO ₂ -based resistance heating elements have almost no conductivity at low temperatures, so they cannot function as self-heating elements, and they have the disadvantage that they cannot be used as heating elements unless they are preheated to a high temperature range with another heater. Ta. Thirdly, as a tool material for cutting tools, die tools for cold and hot working, molds, belt cleaners, and other wear-resistant tools, the structure is uniform, fine, and dense, and it has high hardness and wear resistance. In addition, it must be strong enough to not chip or break, and it must also have excellent thermal shock resistance when used under rapid heating and cooling conditions. Materials that have both of these characteristics are long-lasting and reliable. It becomes a powerful tool material. Carbide tool materials and cermet materials are widely used as these tool materials, but these materials are mainly composed of carbides such as WC and TiC and contain metal components, so they are not suitable for steel materials. Alternatively, ceramic tool materials have the disadvantage of being highly compatible with non-ferrous metal workpieces, and may also have poor wear resistance.As a solution to these problems, ceramic tool materials are effectively used and the demand is sure to increase. It tends to increase. A characteristic feature of the material of the present invention is that the material for decorative members is originally a white material and is made of stabilized ZrO ₂ , which is an insulating material, by adding an appropriate amount of carbide to the material. By making it a flexible material and imparting conductivity, it is possible to use electric discharge machining, which has significantly higher machining efficiency than ultrasonic machining, when machining complex shapes or drilling holes. In addition, heater materials have improved the above-mentioned drawbacks, that is, they have excellent corrosion and abrasion resistance, are tough, and have excellent thermal shock resistance. Furthermore, they have fine constituent crystal grains and a smooth surface, and can be used at low temperatures. Al It is tougher and has better impact resistance than ₂ O ₃ ceramic materials, has improved wear resistance than conventional stabilized ZrO ₂ , and can be processed by electrical discharge machining or electrolytic grinding. It has material properties that can significantly reduce costs. Demand for ceramic materials is increasing for the various uses mentioned above, especially for their high hardness and wear resistance.
Due to the high hardness of ceramic materials such as Al ₂ O ₃ or ZrO ₂ with stable toughness, grinding using a diamond grinding wheel is the mainstream. There is a certain limit to the ability to perform drilling, drilling, etc., and it is often necessary to rely on electrical discharge machining or ultrasonic machining. By the way, Al ₂ O ₃ and
Since ZrO ₂ does not have electrical conductivity, electric discharge machining cannot be used, and ultrasonic machining has had to be relied upon for machining complex and special shapes such as those mentioned above.
However, since the processing efficiency is very low, the product is inevitably expensive, and it may not be possible to meet the price point when developing applications. On the other hand, the electric discharge machining method is generally used for carbide tool materials, etc., and has a machining efficiency several times higher than that of the ultrasonic machining method, and is a better machining method in terms of machining costs. It is an essential condition that the workpiece has electrical conductivity. In view of the above-mentioned current situation, the present invention aims to provide a conductive zirconia-based sintered material and a method for manufacturing the same, which can obtain a material in which conductivity is imparted to a zirconia ceramic, and also enable the use of electrical discharge machining when machining. The gist of the invention is a conductive zirconia-based sintered material and a method for producing the same as described in the claims. Although partially stabilized ZrO ₂ powder differs depending on its manufacturing method, it belongs to a high purity category that usually contains about 0.05% by weight of Al ₂ O ₃ as an impurity. When used, it is customary to mix approximately 1% by weight of Al ₂ O ₃ . In the present invention, stabilization (total and partial stabilization)
As a result of confirming the effect of replacing a part of ZrO ₂ with Al ₂ O ₃ , as will be detailed later, it was found that there is almost no difference in terms of properties when the amount of substitution by Al ₂ O ₃ is 2% by weight or less. Since it was found that 2% by weight of _ZrO2
The following may be substituted with Al ₂ O ₃ . The experiments and examples that led to the development of the present invention and their results will be shown below. <Experiment 1> Various types listed in Table 1 that have been stabilized (including partial stabilization) to contain impurities other than Y ₂ O ₃ as a stabilizer of 0.1% or less and have an average particle size of 0.3 μm.
ZrO ₂ powder with a purity of 99% and an average particle size of 1 μm.
TiC and WC powders were each weighed to be 25% by volume, mixed and pulverized in a wet ball mill, blended with a molding binder as needed, and dried and sized to obtain a raw material for sintering. The above raw material for sintering is processed into a mold press molding machine for 50 min.
After molding at a pressure of Kg/cm2 or ^more , the pre-sintered body was held at a temperature of 1300 to 1650°C for 1 hour in a non-oxidizing atmosphere (Ar gas) furnace to obtain a pre-sintered body with a relative density of 94.5 to 98%. . The above pre-sintering temperature is different for each sample number, so the relative density is 94.5-98% for each sample.
A pre-sintered body was obtained under the temperature conditions. Next, the pre-sintered product was sintered using a HIP device with an inert gas (Ar) pressure of 1500 atm and a temperature 150°C lower than the pre-sintering temperature of each sample number for 1 hour. I got the material. As a sample for investigating the characteristics of the above sintered body, a specimen of 5 x 5 x 25 mm was ground using a diamond grinding wheel.
Various data shown in the table were obtained. Data regarding the evaporation rate was obtained by mirror-lapping each sample and then analyzing everything from minute spots to large spots using an image analyzer.

[Table] <Experiment 2> Same stabilization as used for sample No. 3 in Experiment 1
_ZrO2 powder with purity above 99% and average particle size 0.8~
Various 1.0 μm carbide powders were weighed to give the volume percentages listed in Table 2, and raw materials for sintering, pre-sintered bodies, and HIP sintering materials were obtained in the same manner as in Experiment 1. Various characteristic values listed in the table were obtained. The HIP conditions in this experiment were a temperature 100℃ lower than the pre-sintering temperature, and the inert gas (Ar) pressure was
The pressure was set to 1300 atm and maintained for 1 hour. We also investigated the materials manufactured by the hot pressing (hereinafter referred to as HP) method using all the samples in Table 2 under the optimal conditions to obtain a dense sintered body with a pressure of 50 kg/cm ² or more and a temperature of 1,300 to 1,650°C. Almost the same characteristics as shown in Table 2 were obtained in both cases.

【table】

[Table] <Experiment 3> Same stabilization as used for sample No. 3 in Experiment 1
_ZrO2 powder with purity above 99% and average particle size 0.8~
Various 1.0 μm carbide powders were weighed to give the volume percentages listed in Table 3, and raw materials for sintering, preliminary sintering materials, and HIP sintering materials were obtained in the same manner as in Experiment 1. Various properties listed in Table 4 were obtained. The HIP conditions in this experiment were a temperature 50°C lower than the optimum pre-sintering temperature, an inert gas pressure (Ar) of 1000 atm, and holding for 1 hour.

【table】

【table】

[Table] <Experiment 4> Same stabilization as used for sample No. 3 in Experiment 1
_ZrO2 powder with purity above 99% and average particle size 0.8~
Various composite carbide powders of 1.0 μm were weighed to give the volume percentages listed in Table 5, and raw materials for sintering, preliminary sintering materials, and HIP sintering materials were obtained in the same manner as in Experiment 1. Various properties listed in Table 5 were obtained. The HIP conditions in this experiment were a temperature of 1200℃.
The inert gas pressure (Ar) was set to 1800 atm and maintained for 1 hour.

【table】

[Table] <Experiment 5> Al ₂ O ₃ to fully or partially stabilized ZrO ₂
In order to investigate the effect of the addition of , sintering raw materials having various compositions shown in Table 6 were investigated in the same manner as in the experimental example described above, and the results are also shown in Table 6.

[Table] Example 1 As representative examples of materials for decorative members, the watch side was No. 2, 4, 7, 9 of Experiment 1, No. 2, 3 of Experiment 2,
4, 5, 9, 14, 20, 26, 31, 35, Experiment 3 No.
2, 5, 6, 12, 15, and Experiment 4 No. 2, 5,
Results of a repeated drop test on a wooden floor from a height of 1.5 m on the clock side, which was prototyped using materials 9 and 16, and the inner and stepped parts were subjected to electrical discharge machining followed by finishing, and the outer surface was finished with a grinding lap finish. None of them were damaged, and the appearance of the lap surface was blackish brown (with the exception of No. 31, which had a color close to golden yellow) and had a uniform and beautiful glossy surface. Example 2 A ceramic heater of 10 x 1.5
A 100 mm shaped product was made, 5 wires were connected in series through electrical discharge machining holes in the longitudinal direction, and the temperature was raised with a voltage of 10 volts. As a result, each product reached 400 °C within 5 minutes.
Each of the individual heaters in the array has the same temperature, and as a result of heating the adhered object by placing it directly on the heater instead of using a heating furnace for thermosetting adhesive, the energy consumption rate is 10% lower than that of indirect heating using an electric furnace. %
It turns out that it is possible to save a certain amount. Example 3 The various sintered bodies obtained in the experiments 1 to 4 described above were ground into a cutting tool shape SPGN432, and the cutting conditions were a cutting speed of 450 m/mm, feed rate of 0.2 mm/min, and depth of cut of 0.5.
mm/rev, and as a result of turning a 10% Si-containing Al alloy for 10 minutes, ZrO ₂ partially stabilized with conventional 3% Y ₂ O ₃
The wear width of the flank face was 0.25 mm, while the wear width of the products covered by the present invention was 0.1 to 0.15 mm, which was about the same as that of the superhard alloy K10, but the condition of the turned surface was 0.25 mm.
The surfaces of the products of the present invention were rough due to the welding phenomenon, whereas the surfaces of the products of the present invention were all glossy and exhibited excellent performance. It should be noted that those outside the scope of the present invention often caused troubles such as abnormal wear or chipping, and showed unsatisfactory results. Example 4 As an example of tool material, an extrusion mold (nozzle) was made with the composition of sample No. 14 of the above experiment,
The outer periphery was finished by grinding, and the inner diameter part was subjected to electrical discharge machining, then ground and lap finished to make the bearing part φ1501mm.The result of testing by installing it in an extrusion molding machine was to find that the molding pressure of the conventionally used hardened steel nozzle was 80Kg. / ^cm2 , after extrusion molding a material made by mixing and kneading 10% polyvinyl alcohol with Al ₂ O ₃ weighing 10 kg, the diameter of the bearing was 1607 mm, which was large due to wear, but the product of the present invention was φ1504
mm, and an extrusion mold with extremely excellent wear resistance was obtained. Example 5 Super hard alloy K10 and 99% for wear-resistant materials
Al ₂ O ₃ and No. 8 of Experiment 2 of the present invention, No. 8 of Experiment 3 of the present invention.
7. In Experiment 4, No. 8, a belt cleaner for iron ore belt conveyors was created and subjected to a practical test. As a result, the product of the present invention had 5 times higher concentration than K10 and 3 times higher than 99% A ₂ O ₃ . It was found that it has a long life and is extremely wear resistant. Example 6 Materials according to No. 3 and No. 20 of Experiment 2, die diameter 2.6
As a result of making a wire drawing die of mm and using it for drawing copper wire, it was found that the life of the cemented carbide grade G1 was 20 tons of wire drawing, while the life of the product of the present invention was 32 tons for No. 3 and 32 tons for No. 20. 30
The product of the present invention has a wire drawing life of several tons, and the surface gloss of the wire rod is very beautiful, compared to conventional cemented carbide G1.
The results showed that the product value was significantly higher than that of wire rods. Also, the same sample number as above, nominal diameter 1 inch wall thickness 2
It was also found that dies for processing mm copper pipes had a lifespan 1.3 times longer than conventional cemented carbide. The composition and various properties of the conductive zirconia-based sintered material of the present invention, as well as the manufacturing method conditions for obtaining the same, will be discussed below with reference to the experimental results and examples shown above. In recent years, there have been many publications related to partially stabilized _ZrO2 , and MgO
The high _strength properties _{of ZrO 2 sintered} bodies stabilized with It is difficult to obtain a strong material because there are many phases and fine cracks are likely to occur.
It has been found that when the value exceeds 1, the effect of improving strength due to crystal phase transition is small, resulting in a material that gives unsatisfactory results in terms of breakage resistance. Next, regarding the crystal particle size of the material, if the average particle size exceeds 2.5 μm, even if the material has relatively high strength, it will deteriorate over a long period of time under usage conditions that undergo heating and cooling cycles from room temperature to several hundred degrees Celsius. The monoclinic phase may increase naturally, and the strength may deteriorate naturally. In particular, in order to prevent this natural deterioration phenomenon, it is necessary to suppress the ZrO ₂ crystal particle size to 1 μm or less, and to
This is achieved by suppressing the average crystal grain size of the material to 2.5 μm or less, preferably 2.0 μm or less. Furthermore, if the thickness exceeds 2.5 μm, the strength of the present invention generally tends to be low, and there is a possibility of cracking, chipping, or damage under the usage conditions of tool materials that are subjected to mechanical shock. The larger the crystal grain size, the more spots tend to increase, and the hardness also tends to decrease, resulting in poor wear resistance and a less beautiful lap-finished surface. Welding or abrasion will proceed from this point. If the porosity of the sintered material exceeds 1% by volume, it is undesirable because there are many disadvantages such as wear due to low strength and failure to obtain a beautiful lapped surface due to spots. In particular, mold materials and the like are often subjected to mechanical impact forces, so it is natural that materials with lower strength are more likely to break. The inventors found that the resistance to breakage due to the above phenomenon was determined by the fact that the sharpy value was more closely related to the breakage resistance than the bending strength normally used for ceramic materials, and that the sharpy value was less than 0.1 Kgfm/ ^cm2 . In the case of decorative parts materials, cutting tool materials, cold processing,
It was discovered that there is a possibility of breakage in die tools for hot working. This breakage resistance was also a conclusion obtained from the results of investigating materials for decorative members by drop tests, and the fall distance was set in the range of 1 m to a maximum of 2 m, which is the height at which people handle the materials. Next, regarding the electrical conductivity of the material, if we consider the magnitude of the specific resistance value, the lower the specific resistance value, the easier the electrical discharge machinability will be. There is a limit to 0.5×10 ^-3 Ω when the carbide component is 40% capacity.
equivalent to cm. Even when 40% by volume of carbide components are mixed, it is possible to obtain a material with a resistance of 0.5×10 ^-3 Ω・cm or less depending on the manufacturing method;
This is a phenomenon observed in samples with coarse ZrO ₂ crystal grains, which tend to cause damage and wear due to the decrease in strength and hardness, making them unsuitable for various uses. On the other hand, when the resistivity value exceeds 60×10 ^-3 Ω·cm, electrical discharge machinability suddenly becomes difficult and it becomes impossible to process the material into a special shape. As is clear from Experiment 5 and Table 6 showing the results, 2% by weight of ZrO ₂ partially or entirely stabilized with at least one of Y ₂ O ₃ and MgO.
It was found that even if the following were replaced with Al ₂ O ₃ , there was almost no change in the properties of the material. Next, considering the conditions of the manufacturing method, if the pressurizing force during HP is less than 50 kg/ ^cm2 , products with insufficient density due to insufficient pressurizing force will be produced more frequently, and mold materials and decorative member materials In this case, the wrapping surface becomes cloudy or has a pear-like appearance, and defective products such as spots are likely to be produced, and the life of the tool material is shortened. It goes without saying that the upper limit of the pressing force depends on the strength of the material such as graphite used for the HP type. Furthermore, if the sintering temperature is less than 1300°C, it is difficult to obtain a dense sintered body, and it is not economical as it requires holding for a long time to achieve dense sintering. On the other hand, if the sintering temperature exceeds 1650°C, reaction adhesion with the mold will occur, which will likely result in cracked and defective products, as well as making it impossible to obtain a material with uniform and fine grain size, which will cause a decrease in strength. Therefore, it becomes difficult to obtain a beautiful glossy surface in the appearance of the material for decorative members and the appearance of the product processed with the die tool. Next, the relative density of the pre-sintered body to be subjected to HIP is
If it is less than 94.5%, there may be local density unevenness in the pre-sintered body, and even after HIP processing, a locally insufficient density product will be obtained, and in order to obtain a homogeneous material, must have a relative density of at least 94.5%. In addition, if the holding pressure during HIP is less than 500 atm, products with insufficient density due to insufficient pressure will be produced more frequently, and defective products such as the wrapping surface becoming cloudy, pear-shaped, or having spots. This causes the material to be unsatisfactory as a material for dies, molds, and decorative members, which require a uniform wrapping surface. If the temperature during HIP is less than 1200°C, the HIP effect, that is, densification, will be insufficient due to insufficient temperature. On the other hand, if the temperature exceeds 1650°C, the crystal grain size increases due to oversintering, making it impossible to obtain a product with high strength. As described in detail above, the material of the present invention has high hardness and high toughness, so it can maintain a beautiful glossy surface on the surface of the material for decorative parts and the surface of the workpiece for a long period of time, and it will not break or chip. It has a difficult and uniform fine structure, and can produce blackish-brown and golden-yellow tones, so when applied to various decorative items, it can be used alone or exhibit other color tones. In addition to having a great aesthetic effect when used in combination with parts, it also has a very long life as a heater material, wear-resistant and corrosion-resistant material, and tool material, and can be used in electrical discharge machining and electrolytic grinding with high machining efficiency. Therefore, the economic effect is very large. In particular, by regulating the blended TiC and other carbides and their blending amounts as described above, electrical conductivity is imparted, making it possible to perform electrical discharge machining, making it possible to process products with complex shapes and drilling holes, making it possible to manufacture various decorative items. It has an energy-saving effect as a raw material and heater material, and can have higher hardness than conventional partially stabilized ZrO ₂ , making it an excellent sintering material that extends the life of tool materials.

Claims (1)

[Claims] 1 TiC, NbC, TaC, Cr ₃ C ₂ , ZrC, Mo ₂ C,
The carbide component consisting of at least one type of WC is 17.5 to 40.0% by volume, and the balance is Y ₂ O ₃ and/or
It consists of _two components of ZrO stabilized with 2 to 5 mol% of MgO, and its specific resistance value is (0.5 to 60) ×
A conductive zirconia-based sintered material characterized by a resistance of 10 ^-3 Ω・cm. 2 Claim 1 characterized in that the average particle diameter is 25 μm or less and the porosity is 1% by volume or less
The conductive zirconia-based sintered material described in . 3. The conductive zirconia-based sintered material according to claim 1 or 2, which has a Shalpy impact value of 0.1 Kgfm/cm ² or more. 4 TiC, NbC, TaC, _Cr3C2 , _ZrC , _Mo2C ,
The carbide component consisting of at least one type of WC is 17.5
~40.0% by volume with the remainder being Y ₂ O ₃ and or MgO 2
It consists of _two components of ZrO stabilized at ~5 mol%,
and 2% by weight or less of the ZrO ₂ component (excluding 0)
1. A conductive zirconia-based sintered material having a composition in which is substituted with Al ₂ O ₃ and having a specific resistance value of (0.5 to 60)×10 ⁻³ Ω·cm. 5 Claim 4, characterized in that the average particle diameter is 25 μm or less and the porosity is 1% by volume or less
The conductive zirconia-based sintered material described in . 6. The electrically conductive zirconia-based sintered material according to claim 4 or 5, which has a Shalpy impact value of 0.1 Kgfm/cm ² or more. 7 TiC, NbC, TaC, _Cr3C2 , _ZrC , _Mo2C ,
The carbide component consisting of at least one type of WC is 17.5 to 40.0% by volume, and the balance is Y ₂ O ₃ and/or
A conductive zirconia group characterized by hot press sintering a homogeneous mixed powder of a composition consisting of _two components of ZrO stabilized with 2 to 5 mol% of MgO in a mold of a desired shape in a non-oxidizing atmosphere. Method of manufacturing sintered materials. 8. The method for producing a conductive zirconia-based sintered material according to claim 7, wherein the hot press sintering conditions are a pressing force of 50 kg/cm ² or more and a temperature of 1300 to 1650°C. 9 TiC, NbC, TaC, _Cr3C2 , _ZrC , _Mo2C ,
The carbide component consisting of at least one type of WC is 17.5
~40.0% by volume with the remainder being Y ₂ O ₃ and or MgO 2
A homogeneous mixed powder with a composition consisting of _two components of ZrO stabilized at ~5 mol% is molded into a desired shape, and then the molded body is pre-sintered in a non-oxidizing atmosphere to a relative density of 94.5% or more. A method for producing a conductive zirconia-based sintered material, which is characterized by isostatic pressure sintering (HIP) in a non-oxidizing atmosphere. 10 Isostatic isopressure sintering (HIP) conditions are pressure
10. The method for producing a conductive zirconia-based sintered material according to claim 9, wherein the method is 500 kg/cm ² or more and a temperature of 1200 to 1650°C. 11 TiC, NbC, TaC, _Cr3C2 , _ZrC , _Mo2C ,
The carbide component consisting of at least one type of WC is 17.5
~40.0% by volume with the remainder being Y ₂ O ₃ and or MgO 2
It consists of _two components of ZrO stabilized at ~5 mol%,
and 2% by weight or less of the ZrO ₂ component (excluding 0)
1. A method for producing a conductive zirconia-based sintered material, characterized in that a homogeneous mixed powder having a composition in which Al ₂ O ₃ is substituted with Al 2 O 3 is hot-press sintered in a mold having a desired shape in a non-oxidizing atmosphere. 12 Hot press sintering conditions are pressure 50Kg/cm ²
The method for producing a conductive zirconia-based sintered material according to claim 11, wherein the temperature is 1300 to 1650°C. 13 TiC, NbC, TaC, _Cr3C2 , _ZrC , _Mo2C ,
The carbide component consisting of at least one type of WC is 17.5
~40.0% by volume with the remainder being Y ₂ O ₃ and or MgO 2
It consists of _two components of ZrO stabilized at ~5 mol%,
and 2% by weight or less of the ZrO ₂ component (excluding 0)
A uniform mixed powder with a composition in which Al ₂ O ₃ is substituted is molded into a desired shape, and then the molded body is pre-sintered in a non-oxidizing atmosphere to a relative density of 94.5% or more, and then sintered in a non-oxidizing atmosphere. A method for manufacturing a conductive zirconia-based sintered material, which is characterized by isostatic isostatic pressure sintering (HIP). 14 Isostatic pressure sintering (HIP) conditions are pressure
14. The method for producing a conductive zirconia-based sintered material according to claim 13, wherein the method is 500 kg/cm ² or more and a temperature of 1200 to 1650°C.