Solid Particle Erosion of Brittle Materials (Part 1)

The Relation between Erosive Wear and Properties of Gas Pressure Sintered Si₃N₄

Abstract

Erosive wear by solid particle impingement was tested for 16 kinds of Si₃N₄ which were gas-pressure sintered at different temperatures using different raw material powders containing various amounts of additives. Testing conditions were as follows: # 30 SiC abrasive grains, abrasive grain speed of 250-300m/s and an impingement angle of 80°. The volume eroded was great when the target Si₃N₄ had a low density and large grain size. This corresponds to the tendency that the eroded volume increases with decreasing hardness and fracture toughness. The erosion results were tested four equations that relate the erosive wear to the hardness (Young's modulus) and fracture toughness of the target. The equation V∝H^-1/4K_c^-4/3, which was proposed theoretically by Evans, was found to best describe the experimental results.