LOW TEMPERATURE SINTERING ADJUVANT FOR SILICON NITRIDE AND SINTERING

Title:

LOW TEMPERATURE SINTERING ADJUVANT FOR SILICON NITRIDE AND SINTERING

Document Type and Number:

Japanese Patent JP3127225

Kind Code:

B2

Abstract:

PROBLEM TO BE SOLVED: To obtain a sintering adjuvant for the microwave sintering of a silicon nitride ceramic, and further to provide a sintering method.
SOLUTION: This sintering adjuvant for the microwave sintering of a silicon nitride ceramic is obtained by mixing aluminum oxide, yttrium oxide and magnesium oxide regulated so that the ratio of the aluminum oxide to the yttrium oxide may be within a range of (2:3) to (1:4) and the ratio of the aluminum oxide to the magnesium oxide may be within the range of (1:1) to (4:1). The method for producing the silicon nitride ceramic is the one for growing silicon nitride columnar crystal at a low sintering temperature to provide the silicon nitride ceramic having both high strength and high fractional toughness, and comprises sintering a compact obtained by adding 3-15 wt.% of the sintering adjuvant to a silicon nitride powder and compacting the silicon nitride powder with the added sintering adjuvant by a suitable method, under a normal pressure in a nitrogen atmosphere at 1,500-1,750°C by using a microwave.

Inventors:

Motohiro Toriyama
Kiyoji Hirao
Koji Watari
Manuel E Burito
Masayuki Hirota
Maria Vallesiros

Application Number:

JP33491297A

Publication Date:

January 22, 2001

Filing Date:

November 18, 1997

Export Citation:

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Assignee:

Director of Industrial Technology
New Energy and Industrial Technology Development Organization

International Classes:

C04B35/584; C04B35/64; (IPC1-7): C04B35/584; C04B35/64

Domestic Patent References:

JP10226577A
JP10226576A
JP930867A

Attorney, Agent or Firm:

Masahiko Sudo (1 outside)
Masahiko Sudo

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