An efficient steady-state thermal model for predicting the lack-of-fusion porosity during laser powder bed fusion process

Abstract

Abstract. The lack-of-fusion porosity due to the incomplete melting of the powder should be avoided during laser powder bed fusion (LPBF) process. The porosity will reduce the performance of mechanical properties. In certain manufacturing processes, the thermal and metallurgical quasi-steady-state can be reached quickly. In this article, a steady-state model, incorporating new dedicated boundary conditions, is proposed and applied in the multi-track simulation of LPBF to control porosity. Various processing parameters, such as hatching space and cooling time inter-pass can be investigated. The transient step-by-step simulation is also employed as the numerical reference. Numerical comparisons demonstrate that the proposed steady-state model achieves a relative good agreement with the numerical reference while significantly reducing computing time (2-3 minutes).