Comparison of stellite hardfacing by laser and traditional techniques

Abstract

Stellite coatings were applied to AISI 304 austenitic steel by oxyacetylene torch, TIGand laser techniques and the morphologies of the resulting deposits compared. Stellite deposition by laser was found to give smaller and more uniform dendrite spacing and fewer,smaller interdendritic carbides than the other techniques. These microstructural differences are thought to result from the higher cooling rate obtained with lasers (500—5000 K/scompared with < 10 K/s).