JPS63100065A - Manufacture of nitride sintered body - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a nitride sintered body used for engineering ceramics, tool materials, semiconductor substrates, etc.

[Conventional technology]

S i s N a * T i N t Z r N
+ Nitride sintered bodies such as HfN have high strength, high hardness,
Because it is an elamic with characteristics such as high heat resistance, it is widely used in engineering ceramics, tool materials, semiconductor substrates, etc. However, since the sinterability is very poor, complicated processes such as high temperature and high pressure are required for sintering. (
Ceramics 18 NoI PIO In order to alleviate this problem, measures such as making the original 3:1 powder finer are also being taken. (Machine Materials, April 1985 issue, P5) [Problems to be Solved by the Present Invention] However, the above-mentioned prior art was plagued with difficult process conditions during sintering, and in particular, molding was difficult.

The present invention solves these problems, and provides a nitride sintered body that makes it possible to obtain a window body-like sintered body without requiring high pressure and to easily obtain a molded body. A manufacturing method is provided.

[Means for solving problems]

The method for producing a nitride sintered body of the present invention is characterized in that fine nitride powder is mixed and dispersed in a sol containing a sintering aid component, then gelled, dried, and sintered.

〔Example〕

Example 1 After mixing 15 kg of beryllium propoxide α, 0.3 kg of aluminum isopropoxide, and cerium butoxide (11.1 U) to form a composite alkoxy, 9 was added dropwise to water Q and 5 containing 1 g of hydrochloric acid and hydrolyzed. It turned into a zo/shi.

Fine silicon nitride powder having an average particle size of 911,000 angstroms was mixed into this sol.

This mixed sol was placed in a box-shaped container, sealed, and aged at room temperature for about 3 days to form a gel.Then, the lid was replaced with a lid with a 5% porosity and dried at 60°C to 70°C for 10 days to obtain a dry gel. Ta.

The temperature of this drive p was gradually raised to 1400° C. in a vacuum, and then maintained at 1700° C. for 1 hour in a 1 atm nitrogen atmosphere to obtain a silicon nitride sintered body.

The bending strength was 130 klil/wx2 at room temperature.

Example 2 In Example 1, a female mold in the shape of a turbine blade was made of paraffin, and a sol containing fine silicon nitride powder was injected into it. After being aged into a gel, it was taken out from the paraffin mold, dried and sintered to obtain a sintered silicon nitride turbine blade.

In addition, as a method for forming a complex-shaped silicon nitride sintered body, in Example 1, cutting in a dry gel state and cutting in an intermediate state of sintering during the heating process up to 1400°C are performed. It can also be done easily.

Example 3 Yttrium ethoxide cL2' was mixed with 9 and aluminum isopropoxide α2 to form a composite alkoxide, and 400 cc of water containing 1 g of hydrochloric acid was added dropwise to form a sol. Silicon nitride fine powder tokg and aluminum nitride whiskers α3 obtained by plasma vapor phase method were added to this sol.
9 was mixed into the mixture and stirred.

This was aged in a sealed box type container at 30° C. for 2 days to form a gel, then replaced with a lid having a porosity of 5% and dried at 60° C. for 2 weeks to obtain a dry gel. Put this in a high temperature atmosphere furnace 1
Sintering was performed in a helium atmosphere up to 500°C and in a nitrogen atmosphere up to 1500°C to obtain a silicon nitride sintered body. The bending strength of this sintered body was 150 kg/lus" at room temperature.

Example 4 400 g of yttrium ethoxide was mixed with 100 g of hydrochloric acid acidic Q water.
Hydrolysis and solization were performed using g. 400 g of aluminum nitride fine powder was added, mixed and dispersed into this sol. 10
(After putting the sol in a m square container and aging it at room temperature for 2 days, replace it with a lid with holes with a porosity of 3% and dry it at 70℃ for 10 days. sintered for an hour,
A plate-shaped aluminum nitride sintered body was obtained.

The thermal conductivity of this sintered body was 200 w/m-Ok. The Vickers hardness was 1000 or more.

Example 5 250 g of water mixed with 127 g of ethyl silicate and 204.9 g of aluminum isopropoxide and 3 g of hydrochloric acid α
was hydrolyzed to form a sol. 70 g of ultrafine silicon nitride powder and 82 g of ultrafine aluminum nitride powder were added to this and mixed and stirred. It was placed in a box-shaped airtight container and aged for 2 days at room temperature, then replaced with a lid with a porosity of 10% and dried at 65° C. for 2 hours. The obtained dry gel was sintered in a vacuum at 1500° C. for 2 hours to obtain a sintered body having a sialon composition of SiS Al 4 N 404.

Example 6 200g of 7/reminium propoxylate was hydrolyzed with 21% acidic water, and then 840g of ultrafine silicon carbide powder and 120g of ultrafine silicon carbide powder were added and mixed and dispersed.Example 1 After gelling in the same manner as above, replace the hole with a lid of 75
It was dried for 10 days in a constant temperature bath at ℃.

The obtained solid material was sintered in vacuum at 1600° C. for 1 hour to obtain a mixed sintered body of silicon nitride and silicon carbide.

Example 7 Magnesium methoxide 300I was mixed with hydrochloric acid acidified water 21
640 g of 1TiN powder that had been hydrolyzed was added and mixed. After gelation, drying and firing were performed in the same manner as in Example 1 to obtain a TiN sintered body.

Example 8 Siliconium propoxide 200.9 was added to 250 g of water,
After hydrolyzing with 251 g of hydrochloric acid, 300 g of ZrN@ powder was added and mixed and dispersed. A ZrN sintered body was obtained by aging, gelling, drying, and sintering in the same manner as in Example 1.

Example? After hydrolyzing 250.9 (ethyl silica) with 250 g of water and 2 g of hydrochloric acid, HfN fine powder was added to the solution using soap and mixed and dispersed. The product was aged to form a gel in the same manner as in Example 1, dried and sintered to obtain a HfN sintered body.

〔Effect of the invention〕

According to the present invention, it was possible to easily obtain a sintered body of nitride, which has a high melting point and has been considered to have poor sinterability. In particular, it has become possible to manufacture nitride sintered bodies, which are high hardness, wear resistance, and high heat conductivity heat-resistant materials, using simple equipment without requiring high pressure such as HIP, which was traditionally considered indispensable for sintering nitrides. Ta. It was also possible to produce porous nitride sintered bodies by adjusting the atmosphere and temperature during sintering.

Furthermore, it also has the effect that cutting of the sintered intermediate in the dry stage P state or in the middle of the temperature rising stage I is easy.

A similar effect can be obtained using boron powder.

that's all

Claims (3)

[Claims] (1) A method for producing a nitride sintered body, characterized in that fine nitride powder is mixed and dispersed in a sol containing a sintering aid component, and then gelled, dried, and sintered. manufacturing method. (2) The method for producing a nitride sintered body according to claim 1, wherein the nitride is silicon nitride, aluminum nitride, titanium nitride, zirconium nitride, or hafnium nitride. (3) Sintering aids are BeO, SiO_2, Y_2O_3,
A method for producing a nitride sintered body according to claim 1, which is a simple substance or a composite of rare earth oxides such as Al_2O_3, MgO, ZrO_2, and CeO_2, and is characterized in that a metal alkoxide is hydrolyzed to form a sol. .