Simulating Geometric and Thermal Aspects of Powder-Jet Laser Additive Manufacturing

In order to predict the effects of energy and material deposition via laser and powder-jet based additive manufacturing methods, it is necessary to model a number of appropriate key process phenomena. In addition to solving the classical transient heat equation subject to a moving heat source, it is also critical that local, transient changes in domain geometry and properties also be addressed in order to approach as-build geometry and its associated functional behavior. Furthermore, the melting/solidification behavior of the deposited material may also need to be addressed due to its implications to local temperature-time histories. Finally, incorporating process parameters into a comprehensive simulation is also essential in providing accurate, high fidelity predictions. This work presents efforts at incorporating all of the above-mentioned phenomena via a finite element-based simulation framework to lay the groundwork for full-scale, fully coupled simulations of entire parts. A comparison of predictions including and omitting phase transformation effects along with mass conservation is also presented in the context of assessing the accuracy gained versus the requisite computational expense.