Temperature effects on the tribological behavior of alumina reinforced with unidirectionally oriented SiC whiskers

In the present study, the influence of temperature on the tribological beha vior of alumina reinforced with SiC whisker addition up to 20 vol.% is pres ented. Wear tests were performed at selected temperatures with alumina comp osites prepared by a modified tape casting method. Above a 673 K wear test temperature, the wear and frictional characteristics behaved differently co mpared with tribological behavior at 403 K. The results of this study indic ate that as the temperature increased, the reinforcement effect of the unid irectionally oriented SiC whisker increased and the grain size effect was d ecreased. The effect of whisker orientation on friction and wear characteri stics at the higher temperature was not dependent on test temperatures. The highest wear rate was obtained with a SiC whisker oriented parallel to the tape casting direction at all tested temperatures. The friction and wear m echanism of alumina composites reinforced with SiC at a high temperature is discussed based on SEM observations of worn surfaces and energy dispersion X-ray analysis. (C) 2001 Elsevier Science B.V, All rights reserved.