POWDERY BORON NITRIDE MIXTURE AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To produce a powdery boron nitride mixture having good fillability and sinterability and suitable for use as a material of BN-base refractories. SOLUTION: A boron carbide powder filled body is nitrided at a temp. of >=1,300 deg.C in a nitrogen atmosphere under >=1 kg/cm<2> partial pressure of nitrogen to obtain a sintered body contg. 50-85 wt.% BN. This sintered body is comminuted to obtain the objective powdery boron nitride mixture having >=40 μm max. particle diameter, good fillability and sinterability.