| 摘要 |
PURPOSE:To obtain a ceramic tool material having excellent toughness, hardness and abrasion resistance and giving a tool having long life by uniformly dispersing silicon carbide whisker together with a sintering assistant. CONSTITUTION:A slurry is produced by mixing SiC whisker (10-65vol.%), Si3N4 and its sintering assistant (2-15vol.% based on Si3N4). In the above process, the pH of the slurry is adjusted in such a manner as to give high zeta-potential to the SiC whisker in the slurry or the zeta-potentials of SiC whisker and Si3N4 to have the same sign and high absolute values to cause high electrostatic repulsion and obtain a uniformly dispersed slurry. The slurry is spray-dried under the application of ultrasonic vibration, formed and sintered to obtain a ceramic tool material having high toughness and hardness. The toughness and hardness can be further improved by using a carbide or nitride of a group IV, VA or VIA element, especially TiN, TiC or Ti(CN) as a constituent component. |
