Laser melting modes in metal powder bed fusion additive manufacturing

Additive manufacturing, called 3D printing, has become ubiquitous in classrooms, laboratories, and research centers. While printing with plastics has revolutionized prototyping and modeling, it is now possible to fabricate metal parts and devices directly from computer models by fusing metal particles together with high-intensity lasers. This review focusses on the flow of heat and material in the high temperature environment, the instabilities that arise, and the tools to control them.