National Institute of Advanced Industrial Science and Technology

Denki Kagaku Kogyo Kabushiki Kaisha

Yukihiko Yamauchi

Suzuya Yamada

Shuzo Kanzaki

Shuji Sakaguchi

Kiyoshi Hirao

A boron carbide based sintered body having a four-point flexural strength of at least 400 MPa and a fracture toughness of at least 2.8 MPa&#xb7;m, which has the following two preferred embodiments. (1) A boron carbide-titanium diboride sintered body obtained by sintering a mixed powder of a BC powder, a TiOpowder and a C powder while reacting them under a pressurized condition and comprising from 95 to 70 mol % of boron carbide and from 5 to 30 mol % of titanium diboride, wherein the boron carbide has a maximum particle diameter of at most 5 &#x3bc;m. (2) A boron carbide-chromium diboride sintered body containing from 10 to 25 mol % of CrBin BC, wherein the sintered body has a relative density of at least 90%, boron carbide particles in the sintered body have a maximum particle diameter of at most 100 &#x3bc;m, and the abundance ratio (area ratio) of boron carbide particles of from 10 to 100 &#x3bc;m to boron carbide particles having a particle diameter of at most 5 &#x3bc;m, is from 0.02 to 0.6.

Growing community of inventors

Nagoya, Japan

Yukihiko Yamauchi