Friction and wear behaviour of Al2O3/TiB2/SiCw ceramic composites at temperatures up to 800°C

In this paper, Al2O3/TiB2/SiCw ceramic composites with different volume fraction of SiC whisker were produced, their friction and wear behaviour sliding against cemented carbide at temperatures up to 800°C in air and nitrogen atmospheres has been studied. The friction coefficient and wear rates were examined in relation to SiC whisker content. Results showed that the composition, temperature and atmosphere have an important effect on their friction and wear behaviours. The friction coefficient and wear rates decreased with increasing SiC whisker content both sliding in air and nitrogen atmospheres. The wear mechanism of the composites at temperature less than 400°C was primary abrasive wear, the higher wear resistance of composites with higher SiC whisker content under these circumstances corresponded to their higher value of hardness and fracture toughness. The mechanisms of oxidative wear dominated at 800°C when sliding in air atmosphere, while the wear owing to adhesion and diffusion were suggested to be the main wear mechanism when sliding in nitrogen atmosphere.