Metal additive manufacturing: Principles and applications

Additive manufacturing (AM) of metals has gained massive attention due to its salient features, such as a tool-free process, near-net shape product development, less fabrication time, and no restriction on product size. This paper provides a brief overview of common metal AM processes, including powder bed fusion, binder jetting, directed energy deposition, and sheet lamination. The advantages of each metal AM technology and their limitations are compared and addressed with examples. Critical steps to ensure the successful 3D printing of metal structures are discussed for each metal AM approach. The effect of each processing parameter is critically analyzed to enhance fabrication characteristics. The metal AM mechanisms, optimization of processing parameters, powder preparation techniques and their effects on the powder morphology, and applications of metal AM are discussed.