In order to achieve the desired mechanical properties with AM, the chemistry, microstructure and defects should be controlled. Process inputs such as feedstock quality, build chamber environment, scan strategy, part geometry and AM hardware all affect the thermal and physics interactions to determine the extent, size, and shape of defects and microstructure. These thermal and physics interactions can be explained similarly to welding process variables such as power, speed, beam interactions, heat transfer, and process temperature that determines solidification kinetics and subsequently phase distribution and grain morphology.