Metal Additive Manufacturing

An additive manufacturing machine builds a part layer by layer from powder or wire instead of cutting it from stock. In laser powder bed fusion, a recoater spreads a thin layer of metal powder and one or more lasers melt the cross-section of the part into it, layer after layer, in an inert atmosphere. Electron beam machines do the same with a beam in vacuum. Directed energy deposition feeds powder or wire into a melt pool and can add material to an existing part.

The process earns its place where geometry is the problem: internal cooling channels, lattice structures, several parts consolidated into one, or low volumes of a part that would otherwise need tooling. Printed parts are rarely finished parts. Support removal, heat treatment and machining of the functional surfaces follow, typically on a 5-axis machining center, and a wire EDM often cuts the parts off the build plate.

Compare the build volume first, then the number of lasers and the power of each, which set the build rate. Layer thickness and focus diameter relate to detail and surface quality. Ask which materials the maker has qualified, how powder is handled and sieved, and what the machine needs in inert gas and power.