THE EFFECT OF LASER-SURFACE MELTING ON THE EROSION BEHAVIOR OF A LOW-ALLOY STEEL

The objective of the present work is to evaluate the resistance of a l aser-surface-melted 0.4% C low alloy steel to solid particle erosion. Towards this purpose, steel samples heat treated to two different base Vickers hardness levels, namely HV 350 and HV 550, were subsequently laser surface melted up to a depth of about 800 mum, resulting in hard nesses of HV 500 and HV 660 respectively. An air jet erosion tester ut ilizing SiC particles as erodent was used for comparing the erosion be haviour of laser-treated steels with those of untreated steel and anne aled Armco iron (HV 76). Erosion tests were carried out at two impact velocities (46 and 96 m s-1) and three impact angles (30-degrees, 60-d egrees and 90-degrees). The results indicate that laser surface harden ing does not improve the erosion resistance of a 0.4% C steel and that the erosion rates of the steels are very similar to that of annealed Armco iron.