Solid particle erosion behavior of an Si3N4–MoSi2 composite at room and elevated temperatures

The solid particle erosion behavior at room and elevated temperatures (180, 500, 700 and 900°C) of an Si3N4–MoSi2 composite was studied. Alumina particles entrained in a stream of nitrogen gas impacted the target material at a velocity of 40 m s−1. Impingement angles of either 60, 75 or 90° were used. It was found that the erosion rate for the Si3N4–MoSi2 composite (measured at room temperature) was a maximum at the 90° incident angle, erosion behavior typical of brittle materials. The erosion rate of the composite at a 75° impingement angle increased slightly with increasing test temperature up to 700°C (i.e. from 4.1 to 4.9 mm3 g−1). At 900°C, the measured erosion rate decreased to 2.9 mm3 g−1. The erosion behavior of the Si3N4–MoSi2 composite was compared to that of commercially available Si3N4, WC–6%Co, 304 SS, IN-800 (Ni–Fe–Cr alloy) and Stellite-6B (Co–Cr–W–Mo alloy).