A review on powder bed fusion technology of metal additive manufacturing

Additive manufacturing (AM) is a novel method of manufacturing parts directly from digital model by using layer-by-layer material build-up approach. This tool-less manufacturing method can produce fully dense metallic parts in short time with high precision. Features of AM like freedom of part design, part complexity, light weighting, part consolidation, and design for function are garnering particular interests in metal AM for aerospace, oil and gas, marine and automobile applications. Powder bed fusion, in which each powder bed layer is selectively fused using energy source like laser or electron beam, is the most promising AM technology that can be used for manufacturing small, low volume, and complex metallic parts. This review presents evolution, current status, and challenges of powder bed fusion technology. It also compares laser and electron beam-based technologies in terms of performance characteristics of each process, advantages/disadvantages, materials, and applications.