Showa Denko K.k.

Showa Dendo K.k.

Makoto Iizuka

Eiji Ihara

Hirohiko Ohtsubo

Makoto Kasahara

Takuya Okubo

The present invention relates to a method for producing cubic boron nitride abrasive grains used for producing a grinding wheel, etc., and to cubic boron nitride abrasive grains. The method comprises maintaining a mixture containing hexagonal boron nitride and seed crystals of cubic boron nitride under pressure and temperature conditions where cubic boron nitride remains thermodynamically stable, characterized in that the seed crystals contain cubic boron nitride twin crystals.

Method for producing cubic boron nitride abrasive grains

A method for producing cubic boron nitride includes maintaining hexagonal boron nitride in the presence of a catalyst substance under conditions where cubic boron nitride remains thermodynamically stable to thereby transform hexagonal boron nitride into cubic boron nitride, wherein the catalyst substance contains LiMBN, in which M represents Ca, Sr, Ba, Ra, Be, or Mg, and at least one species selected from the group consisting of alkali metals, alkaline earth metals, nitrides thereof and boronitrides thereof. Any one of the LiMBN, alkali metals, alkaline earth metals, nitrides thereof and boronitrides thereof has an oxygen content of% or less. As a result, the percent transformation into cubic boron nitride can be considerably enhanced, and the cubic boron nitride obtained exhibits high mechanical strength.

Growing community of inventors

Shiojiri, Japan

Makoto Iizuka