Influence of ball milling on the sintering behaviour of ZnO powder

A high purity ZnO powder was milled with either YSZ or Al2O3 balls. The weight losses of YSZ and Al2O3 balls after milling for 4 h are 10 and 40 ppm, respectively. The debris of the milling media acts as sintering aid to the ZnO powder. As a result, the grain size of the sintered ZnO specimens is reduced. The ratio of the grain boundary energy over surface energy is also decreased.