Dynamic evolution simulation of sintering pool in selective laser sintering walnut shell/Co-PES composite

Abstract

In view of the difficulties in the observation of sintering pool and too many factors influencing the dynamic evolution process of sintering pool during the selective laser sintering (SLS) process of biomass composite materials, the structural morphology of sintering pool during the SLS process of walnut shell/Co-PES (WSPC) powder and its dynamic evolution process were studied. Based on the DFLUX subprogram, a moving double ellipsoid heat source model was established. Considering heat conduction, heat radiation, heat convection and thermophysical parameters changing with temperature, the three-dimensional finite element model of WSPC powder was numerically simulated in the process of SLS. Through numerical simulation analysis, the surface shape of sintering pool is circularand the cross section one is deep bowl, and the sintering forming process is a process in which the sintering pool is continuously superposed along the sintering direction. By comparing the experimental results with the numerical simulated results, the experimental results are in good agreement with the simulated results. The dynamic evolution law of sintering pool during SLS process of WSPC powder and the change law that sintering pool size increases with the increase of preheating temperature and laser power and the decrease of scanning speed were obtained.