A Sensitivity Analysis Study on the Material Properties and Process Parameters for Selective Laser Melting of Inconel 625

Abstract

A prediction of the 2-D temperature profile and melt pool geometry for Selective Laser Melting (SLM) of Inconel 625 metal powder with a numerically-based approach for solving the heat conduction-diffusion equation was established in this paper. A finite element method solution of the governing equation was developed. A review of the current efforts in numerical modeling for laser-based additive manufacturing is presented. Initially, two-dimensional (2-D) temperature profiles along the scanning (x-direction) and hatch direction (y-direction) are calculated for a moving laser heat source to understand the temperature rise due to heating during SLM. The effects of varying laser power, scanning speed and the powder material’s density are analyzed. Based on the predicted temperature distributions, melt pool geometry, i.e. the locations at which melting of the powder material occurs, is determined. The results are chiefly compared against the published literature on melt pool data. The main goal of this research is to develop a computational tool with which investigation of the importance of various laser, material, and process parameters on the built dimensional quality in laser-based additive manufacturing becomes not only possible but also practical and reproducible.