Silicon nitride sintered body and process for preparation thereo

Details Silicon nitride sintered body and process for preparation thereo Silicon nitride sintered body and process for preparation thereo

1986-07-29

1990-01-09

Bell, Mark L.

Plastic and nonmetallic article shaping or treating: processes

Including step of generating heat by friction

264 66, 501 97, 501 96, C04B 3558

Patent

active

048928488

ABSTRACT:
Disclosed is a process for the preparation of a silicon nitride sintered body, which comprises steps of (i) molding a composition comprising (a) 87 to 98% by weight of silicon nitride and (b) 2 to 13% by weight of a sintering aid comprising an oxide or nitride of aluminum or an element of the group IIIa of the Periodic Table and an inorganic oxide capable of forming a liquid phase component having a melting point lower than that of silicon nitride, the inorganic oxide being present in an amount of 1 to 7% by weight based on the composition, (ii) sintering the molded body in a nitrogen atmosphere at a temperature forming a liquid phase containing said liquid phase component having a low melting point, and (iii) heat-treating the resulting sintered body in a nitrogen atmosphere at a temperature higher than the sintering temperature to volatilize the liquid phase component having a low melting point from the liquid phase.
In the obtained sintered body, the oxygen content in the surface layer is controlled below 3% by weight, and the flexural strength at 1300.degree. C. of the surface layer is higher than that of the inner portion.

REFERENCES:
patent: 3811928 (1974-05-01), Henney et al.
patent: 4004937 (1977-01-01), Masaki
patent: 4280850 (1981-07-01), Smith et al.
patent: 4327187 (1982-04-01), Komatsu et al.
patent: 4356136 (1982-10-01), Mangels
patent: 4499192 (1985-02-01), Shimamori et al.
patent: 4603116 (1980-07-01), Smith et al.
patent: 4615990 (1986-10-01), Richon et al.

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