Effect of microstructure on the erosion behavior of carbon steel

Solid particle erosion of steel is a function of abrasive particle properties, target material, erodent velocity, abrasive feed rate, impact angle and the environment. Steel microstructure, which directly influences its hardness and ductility, plays an important role in determining the erosion rate. In this study, the effect of microstructure on the erosion of AISI 1018 (pearlite+ferrite) and AISI 1080 (pearlite) steel is investigated. Particle velocities and impact angles employed were as follows: 36, 47, 56 and 81 m s−1 at 30°, 45°, 60° and 90°, respectively. Nano-indentation was performed and it was found that hardness of the various microstructures has an inverse relationship to erosion rate. It was also found that, contrary to expectation, at low impact angle, AISI 1018 steel exhibits higher erosion resistance than AISI 1080 steel. Surface and sub-surface examinations were conducted using scanning electron microscopy. Ploughing, metal cutting and delamination are identified as dominant mechanisms during erosion of AISI 1018 and AISI 1080 steel. It was observed that pearlitic and ferritic microstructures respond differently to erosion and that the orientation of pearlite plates with respect to the impinging particle affects the extent of metal removal.