Effect of microstructural orientation on erosion behavior of self-reinforced silicon nitride

Erosion tests were conducted on silicon nitride containing uniaxially oriented large elongated grains using silicon carbide angular particles at impact angles from 45 to 90°. Two different impact directions were selected to investigate the effect of elongated grain orientation on erosion behavior of self-reinforced silicon nitride. Erosion weight loss after impact of SiC particles was measured and the erosion behavior depending on impact angle and grain orientation were studied. Higher erosion rate was obtained in the normal direction with respect to the aligned large grains in all tested impact angles. The erosion models based on grain pullout and lateral cracking were proposed to explain the observed anisotropic tendency in erosion behavior of self reinforced silicon nitride at the low impact angle.