High-temperature abrasive wear characteristics of H13 steel modified by laser remelting and cladded with Stellite 6 and Stellite 6/30% WC

Abstract

The study is aimed to analyse the comparative behaviour of the high-temperature abrasive wear of H13 steel surfaces modified by laser melting and cladding with Stellite 6 and Stellite 6 + 30 wt% WC. 3-body abrasive tests were conducted at room temperature, 450 °C, 550 °C, and 650 °C. The microstructural evolution, microhardness, wear surface morphology and mechanisms, and various phases formed during laser surface modifications were also studied. The laser remelting of H13 steel surface increased its room temperature microhardness to 750 ± 35 HV0.01, whereas laser cladding of Stellite 6 powder yielded hardness of around 600 ± 20 HV0.01 in the clad layer; and Stellite 6/WC composite clad layer had marginally higher hardness than the Stellite 6 clad layer in the matrix and much higher hardness of ~3000 HV0.01 at the sporadically distributed WC particle sites. Though the room temperature microhardness of laser remelted H13 surface is the highest, the volumetric wear loss in it was comparable to that of the Stellite 6 cladding. However, Stellite 6/WC composite layer recorded a relatively less volumetric loss as WC particles resisted the abrasive wear. With increasing temperature, the wear loss in laser remelt surfaces increased at a fast rate, while that in Stellite 6 and composite clad layers varied marginally with no definite trend. Overall, Stellite 6/WC composite cladding performed better than others in the current temperature range.