(1) Synthetic Crystal Research Laboratory, Faculty of Engineering, Nagoya University, 464 Chikusa-ku, Nagoya, Japan;(2) Toyota Central Research and Development Laboratories, Inc., 480-11 Nagakute-cho, Aichi Pref., Japan
Abstract:
TiB2 powder was synthesized by solid state reaction using amorphous boron and TiN as a source of titanium. The TiB2 formation did not occur at all in a nitrogen atmosphere even at 1400° C. TiB2 formed above 1100° C in argon and hydrogen atmospheres. The only crystalline phase of TiB2 powder was favourably synthesized at 1400° C for 360 min in an argon atmosphere from a starting powder with a composition containing excess boron (B/Ti = 2.2). The synthesized powder was well dispersed and had a particle size of 0.5 to 2 µm. The powder activity was evaluated by sintering at 4 G Pa and 1300 to 1600° C for 15 min.