An experimental investigation of heat affected zone formation and morphology development during laser processing of metal powder mixtures

Laser-induced melting and subsequent resolidification of a metal powder mix ture consisting of low and high melting temperature materials was experimen tally examined. First, the onset of melting for the low melting point mater ial was determined and correlated with dimensionless parameters. Next, the morphologies of the heat affected zones were categorized and finally, a pro cess map for use in rapid prototyping technology was developed. The results indicate a strong dependence of the system behavior on the laser-material coupling efficiency and in turn, the ratio of the laser beam radius to part icle size.