PRODUCTION OF HIGH TOUGHNESS SILICON NITRIDE SINTERED BODY

摘要

PURPOSE:To produce a silicon nitride sintered body having high fracture toughness. CONSTITUTION:A prescribed amt. of a sintering aid, etc., is added to powdery starting material prepd. by adding 20-30wt.% coarse silicon nitride powder having >=1mm average particle diameter to 70-80wt.% fine silicon nitride powder having <1mum average particle diameter and >=90% alpha-silicon nitride content. They are molded and sintered in compressed nitrogen. A high toughness silicon nitride sintered body is easily obtd. without using a high pressure device.