A comprehensive analytical model for laser powder-fed additive manufacturing

This paper addresses a comprehensive analytical model for the laser powder-fed additive manufacturing (LPF-AM) process, also known as directed energy deposition AM. The model analytically couples the moving laser beam with Gaussian energy distribution, the powder stream and the semi-infinite substrate together, while considering the attenuated laser power intensity distribution, the heated powder spatial distribution and the melt pool 3D shape with its boundary variation. The particles concentration on transverse plane is modeled with Gaussian distribution based on optical measurement. The model can effectively be used for process development/optimization and controller design, while predicting adequate clad geometry as well as the catchment efficiency rapidly. Experimental validation through the deposition of Inconel 625 proves the model can accurately predict the clad geometry and catchment efficiency in the range of specific energy that is corresponding to high clad quality (maximum percentage difference is 6.2% for clad width, 7.8% for clad height and 6.8% for catchment efficiency).