Optimization of processing parameters for LPBF-manufactured CoCr alloys based on laser volume energy density

Abstract

In this paper, the finite element method (FEM) and experiments were adopted to optimize the processing parameters of laser powder bed fusion-manufactured cobalt-chromium (CoCr) alloys on the basis of laser volume energy density. According to simulation results, both the maximum temperature, heat-affected zone and cooling rate of molten pool increased with the enhancement of laser power and scanning speed even under the same laser volume energy density. By conducting relevant experiments, it is found that the phase transformation, microstructure and mechanical properties were also influenced by the variation of laser power and scanning speed, and the LPBF-processed CoCr alloys with excellent forming quality could be acquired when the laser power was 160 W, and the scanning speed was 750 mm/s. Therefore, it is impracticable to optimize the processing parameters only on the basis of laser volume energy density, various methods should be employed to complete the whole optimization procedure.

Keywords

• Laser powder bed fusion
• Finite element simulation
• Laser volume energy density
• CoCr alloy