Effect of microstructure on the erosion of steel by solid particles

Abstract

The effect of microstructure on the erosion of AISI-SAE 1078 and 10105 steels by 240 grit A1 2O 3 particles was investigated at particle velocities V of 40–100 m s −1 and angles of impingement a of 10°–90° relative to the target surface. The microstructures investigated included spheroidite, pearlite, martensite and tempered martensite. Spheroidite and pearlite microstructures eroded by the ductile mode at all velocities, exhibiting a maximum erosion rate at an impingement angle of 40°. The effect of the angle of impingement on the erosion rate of martensite and tempered martensite varied with particle velocity, the erosion mode tending towards a brittle mode with increasing velocity. At all angles of impingement the erosion rate tended to increase with the volume fraction of Fe 3C. Examination of the eroded surfaces by scanning electron microscopy showed the occurrence of localized plastic flow of appreciable magnitude. No subsurface cracking or void formation was evident. The erosion rate E r could be considered to vary with particle velocity according to the power law E r = kV n where n has a value of about 2 independent of the microstructure and the angle of impact.