Feed-Forward Controls for Laser Powder Bed Fusion Based Metal Additive Manufacturing

The research objective of the proposed work is to develop a concept for a feed-forward control (FFC) hardware, algorithms, and multi-physics-based models to allow real-time tracking of powder bed layer variability and corresponding laser processing parameter compensation to improve the quality of laser fusion-based metal additive manufacturing (AM) parts. The FFC concept is designed to compensate for the systematic physical property variabilities of the powder bed layer arising from the non-uniformity of thermal evolution for the AM build and recoat layer powder. This includes the characterization of systematic layer thickness variability that is caused by splatter, molten particle ejects, denudation zones, and the previous layer surface roughness. The proposed FFC compensation algorithms build upon the predictions of multi-physics models in order to minimize defects and the non-uniformity of microstructure, which arise from the inconsistency of the melt-pool shape and its solidification behavior. The parameter compensation is designed to predict the current, relevant information using off-the-shelf hardware and data-reduction procedures that have been demonstrated. The Phase I will refine these procedures and the hardware utilization for real-time FFC application. It will also specify a range of parameter variables for the purpose of model development, system verification, and technology validation.