Solid-state additive manufacturing and repairing by cold spraying: A review

High-performance metal additive manufacturing (AM) has been extensively investigated in recent years because of its unique advantages over traditional manufacturing processes. AM has been applied to form complex components of Ti, Fe or Ni alloys. However, for other nonferrous alloys such as Al alloys, Mg alloys and Cu alloys, AM may not be appropriate because of its melting nature during processing by laser, electron beam, and/or arc. Cold spraying (CS) has been widely accepted as a promising solid-state coating technique in last decade for its mass production of high-quality metals and alloys, and/or metal matrix composites coatings. It is now recognized as a useful and powerful tool for AM, but the related research work has just started. This review summarized the literature on the state-of-the-art and problems for CS as an AM and repairing technique.