アルミナの疲労強度特性に及ぼす結晶粒径と添加強化材の影響

抄録

In order to study the influence of the grain size and PSZ reinforcement on fatigue strength characteristics of alumina, cyclic fatigue tests were carried out on sintered alumina (Al₂O₃) with a surface crack. The crack was introduced by Vicker's indentation method under two load levels, 98N and 294 N. Fatigue strength tests were conducted at a constant stress ratio R(=0. 1) and constant frequency f(=50 Hz). It is shown that there is large influence of grain size on fatigue strength characteristics and the larger-grained alumina has a longer fatigue life. It is also found that PSZ reinforcement is effective in enhancing the fatigue strength of alumina.