Numerical Modeling of Selective Laser Melting: Influence of Process Parameters on the Melt Pool Geometry

An efficient approach for virtual prediction of melt pool geometry and temperature distribution in selective laser melting (SLM) is required to optimize the process parameters for eventually printing high-fidelity parts. In this study, the melt pool geometry in the SLM process was simulated by employing Ansys Additive, the commercial finite element analysis software tool. First, a single track of 4 mm length was modeled for Inconel 718 material by varying the process parameters. Validations with existing studies were performed to ensure the reliability of the FE model. Further, a process map exhibiting the optimum process parameters window for SLMed Inconel 718 was developed, which can be used to avoid process-induced defects such as lack of fusion, balling, and keyholing. The response surface methodology design of experiment technique and ANOVA-based regression modeling were used to relate the vital SLM process parameters with the melt pool geometry. The statistical analysis results showed that maximum melt pool depth and width are obtained at maximum laser power and at minimum scan speed and layer thickness. The proposed approach facilitates robust 3D printing by avoiding common process-induced defects as well as allows the tuning of vital process parameters for fabricating superior quality SLM builds.