摘要 |
A composition suitable for the production of ceramics is provided. The composition comprises a particulate material which is a nitride, carbide, carbonitride or boride of Ti, Zr, Al, Si or B having a coating on the particle comprising 5 to 75 wt% with respect to particulate material of an oxide or hydrous oxide of zirconium. The composition can be used to produce a tough zirconia/non-oxide ceramic without the need to co-mill the ingredients. A stabilising agent for the zirconia may also be present in the coating although the invention is designed to avoid the necessity for such agents. Coating usually is effected by a wet treatment process in which the particles are dispersed in a solution of a hydrolysable zirconium salt and the oxide or hydrous oxide is coated on the particles by adjusting the pH of the dispersion. |