Figure1
Figure 1. Process parameters in the PBF process, which affect the process mechanisms and defect formation in AM. DED processes also share similar defects, though the formation mechanisms may differ slightly. Illustrated here are the uncovered mechanisms for PBF, which include powder spreading [68], melting [69], spattering [43] and vapor plume [70]. The defects range from gas, keyhole pores, lack of fusion pores to cracks [71], delamination [72] and distortion [73].