JPS61291460A - Manufacture of fiber reinforced silicon carbide ceramic - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for manufacturing a silicon carbide ceramic reinforced with 9M fibers.

<Prior Art> Ceramics reinforced with fibers such as whiskers are known to have significantly improved mechanical properties, but are extremely difficult to manufacture.

This may be because it is difficult to uniformly mix the fibers and ceramic powder, but more importantly, the taAH portion is relaxed due to shrinkage of the ceramic molded body during firing.
This is because the reinforcing effect of iJ&miscellaneous is lost.

In order to produce a reinforcing effect, it is necessary to suppress shrinkage during firing.

<Problems to be Solved by the Invention> The present invention has been made in view of the above problems, and aims to provide a new manufacturing method that can suppress shrinkage during firing and maintain the reinforcing effect of fibers. It is.

<Means for Solving the Problems> The inventors of the present invention have conducted intensive research regarding the above-mentioned problems, and as a result have obtained several new findings. That is, mixing silicon carbide fibers or whiskers with carbon powder, or mixing silicon carbide fibers with carbon powder or silicon carbide powder,
After molding and firing into a porous body in advance, the porous body is impregnated with molten silicon to produce a sintered body using a so-called reaction sintering method in which silicon carbide is produced by avoiding the reaction between the carbon and silicon in the porous body. It was found that the reinforcing effect was sufficiently maintained without the fibers relaxing.

The present invention has been made based on the above findings.

<Example> The invention will be explained by way of examples.

Example 1 Silicon carbide whiskers and carbon powder in a weight ratio of 3:1
Mix in the ratio of 10×10×50I by adding peptizer to this and making a slip for casting molding
This primary molded body, which was formed into a wR plate shape, was dried and then heated and fired at 800° C. in an argon atmosphere to produce a secondary molded body.

Next, molten silicon was infiltrated into this molded body at 1500°C.

The bending strength of the fired body obtained by the present invention is 80 to 9/
It was 2nd boat.

Incidentally, the bending strength of ordinary silicon carbide that has not been reinforced with fiber reinforcement is 50 to 60 K9/tm''.

Example 2 A slip for casting was prepared in the same manner as in Example 1 by mixing silicon carbide whiskers, silicon carbide powder, and carbon powder at a weight ratio of 6:2:3, and the same procedure as in Example 1 was carried out. The size of the test pieces, which were made into single-character molded bodies and double-character molded bodies and impregnated with silicon, was the same i ox i as in Example 1.

×10oIRI4.

The bending strength of the obtained fired body is 70 Kg/tm2
Met.

From Examples 1 and 2 above, it was confirmed that the method of the present invention can sufficiently exhibit the reinforcing effect of fibers.

<Effect of the invention> 1> Can be fired without loosening the fibers.

2) The process is simple.

Claims (1)

[Claims] After firing silicon carbide fibers or whiskers and carbon powder, or a mixture of silicon carbide fibers or whiskers, silicon carbide powder, and carbon powder into a porous body, the porous body is impregnated with molten silicon to react with the carbon in the porous body. A method for producing a fiber-reinforced silicon carbide ceramic, which comprises at least producing silicon carbide.