The NASA application is to enable physics-based selection of SLM process parameters to mitigate defects and to control microstructure for a variety of aerospace materials. It is designed to reduce the effect needed to fulfill the certification requirements for parts manufactured for NASA. This application is needed because the commercially available SLM systems are based on parameters designed by trial and error, and only for a few alloys and powders. This work is expected to reduce this effort to design an SLM process for new alloy by a factor of ten. Physics-based selection of SLM process parameters to mitigate defects and to control microstructure for a variety of materials utilized in land or sea-based gas-turbine engines, for life-extension of aging systems, repair of jet engine components for commercial aircraft, etc.