Analysis on selective laser melting of WC-reinforced H13 steel composite powder by finite element method

A three-dimensional finite element model for the selective laser melting process was developed to analyze the melting behavior of WC-reinforced H13 steel composite powder. In this model, convection and radiation on the external surface during laser irradiation were considered, and moving Gaussian heat flux was assumed in the thermal model. The molten pool geometry based on the simulated temperature distributions was investigated for various parameters such as distribution factor, packing efficiency, absorption coefficient, and specific heat factor. The input values of density, conductivity, and specific heat were obtained from the rule of mixture, and absorption coefficients were experimentally determined at given mixing ratios of WC and H13 steel. The simulation results showed that the relative fractions of WC and H13 steel powder significantly affect molten pool geometry. In terms of point-of-process parameters, the distribution factor, packing efficiency, and absorption coefficient are the main parameters that control molten pool geometry.