Thermal Control in Additive Friction Stir Deposition

Additive friction stir deposition (AFSD), more commonly known as MELD, enables bulk, solid-state deposition of metals at orders of magnitude faster than power bed technologies. As the technology enables additive deposition of metals with forged microstructure, there is tremendous interest in using the technology to create increasingly large structures as a means of reducing the lead time on large forgings. One of the challenges these larger builds creates relates to the variation of heat that is generated throughout the build, as the base increases in mass and temperature in comparison to the original build-plate. We demonstrate how in-process thermal control can be achieved, and how PID settings need to be adapted to accommodate variation in the an additive build to maintain stable control parameters.

Keywords: AFSD, MELD, Aluminum, control