Investigation of novel trochoidal toolpath strategies for productive and efficient directed energy deposition processes

Directed energy deposition (DED) is an additive manufacturing technology where a moving energy source creates a meltpool on the surface of a substrate into which feedstock material is deposited to form the final part geometry. Maintenance of the meltpool during deposition requires very high intensity energy flux to overcome thermal losses to the surroundings and substrate. Trochoidal toolpaths are investigated using numerical simulation and DED experiments as a means of increasing the efficiency of the DED process. Trochoidal laser motion during DED was found to increase the material addition rate by 17% and powder catchment efficiency by 15%. (C) 2019 Published by Elsevier Ltd on behalf of CIRP.