Heat transfer in granular medium for application to selective laser melting: A numerical study

In this study, the heat transfer in a granular medium due to a moving laser source is investigated numerically. A numerical model on laser energy absorption and its transport in granular media is presented. This process is especially relevant to laser melting/sintering of metal powders. The non-continuum approach is used to consider the discrete nature of granular medium explicitly. The validation of each of the individual modules of the thermal model is presented. The simulation results demonstrate the ability of numerical approach to predict powder bed properties and influence of laser melting/sintering process variables (grain size, material emissivity, substrate property etc.) on laser energy distribution and transport in the powder bed.