Optimization of processing parameters for laser powder deposition using finite element method

Abstract

In order to investigate the effects of powder materials and processing parameters on thermal and stress field during laser powder deposition (LPD), a finite element model was developed with the help of ANSYS software. The finite element model was verified by the comparison between the experimental results and computed results. Then LPD processes with different powder materials and processing parameters were simulated by using the FE model. The results show that less difference of thermal conductivity and thermal expansion coefficient between powder material and substrate material produces lower residual stress; higher laser power, laser scanning speed and smaller laser beam diameter can lead higher peak temperature and higher residual stress. The research opens up a way to rational selection of the powder materials and processing parameters for ensured quality.

Keywords

laser powder deposition / thermal field / stress field / powder material / processing parameters

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