Simulation of the densification of semicrystalline polymer powders during the selective laser sintering process: Application to Nylon 12

The processes of heating and densification of semicrystalline polymer powders during the selective laser sintering process are simulated using the finite element method. Based on a previously developed three-dimensional approach for the sintering of amorphous polymer powders, the modeling methodology is extended to semicrystalline polymers by taking into account the effects of latent heat during melting. In these simulations, the temperature-dependent thermal conductivity, the specific heat, the density, and the effect of latent heat are computed and then used as material constants for the integration of the heat equation. Results for the temperature and density distribution using Nylon-12 powder are presented and discussed. The effects of processing parameters on the density distribution are also presented.