Patent ID: 7153484
Filing Date: 2006-12-26
Classification: C04B,Y02E

Abstract:
1. A producing method of a porous Si 3 N 4 , comprising the steps of: (a) mixing, as a first sintering agent, powder of at least one compound of a rare earth element in an amount of 7.5–45 parts by mass in terms of an oxide of the element with respect to 100 parts by mass of Si powder to obtain mixed powder; (b) adding a binder to the mixed powder; (c) molding the mixture of the mixed powder and the binder into a molded body; (d) heating the molded body in a nitrogen atmosphere to 300–500° C. to remove the binder therefrom to form a binder-removed body; (e) nitriding the binder-removed body by heating the same in a nitrogen atmosphere to 1350–1500° C. to form a nitrided body including Si (f) sintering the nitrided body at 1750–1900° C. at a nitrogen pressure of 0.1–0.5 atmosphere to make Si