FRICTION AND WEAR OF SINTERED ALUMINA AT HIGH-TEMPERATURE

The frictional behavior of alumina ceramics was investigated at various temperatures up to 1200-degrees-C. The coefficient of friction decreased with increasing temperature and this dependence became more pronounced as higher contact pressure was applied. Wear loss at room temperature could be interpreted as being caused by one of two different behavior modes which have a rate difference of an order of magnitude. At temperatures higher than 800-degrees-C, the wear loss was far less than that at lower temperatures and a smooth, flat friction surface, which is probably responsible for both the low friction coefficient and the small wear loss, was observed.