Additive manufacturing (AM) (also know as 3D printing) is the process of manufacturing objects directly from 3D model data, typically using a layer-by-layer material build-up strategy. Metal AM is a tool-less process that can manufacture fully dense metal parts quickly with high precision. This introduction and overview of AM focuses on two major metal AM processes, powder bed fusion-based technologies (PBF) and directed energy deposition (DED)-based technologies.

However, the paper is much more than just a technology exposition. In addition to a well-done technology discussion, it covers applications of the technology as well as advantages and disadvantages, challenges, and economics of AM. Included are 23 figures, which represent many different types of information-rich graphics (many worth a thousand words) that exemplify the writing. A case in point is a discussion of where AM can get complexity for free in comparison to conventional manufacturing.

Because AM is an extremely important new technology trend, nearly everybody should want to learn more about it. This 12-page paper is a Rosetta stone for understanding 3D printing. Everyone from the casual observer who needs an introduction to the topic to the expert who can always use a useful reference should find this paper invaluable. The paper is therefore highly recommended.