Effect of build platform location and part orientation on dimensional accuracy of downfacing surfaces in LPBF

Additive Manufacturing (AM) technologies are creating pathways for a digital transition in manufacturing and the Laser Powder Bed Fusion (LPBF) process remains the most promising and successful technology in this regard. This has inspired research and development efforts to further capabilities and to push the state of the art in order to open up even more applications. Down-facing features are one of the most critical features within all LPBF parts and this work presents an investigation on the effects of build platform location and part orientation on the dimensional accuracy of printed part. This work makes evident that the pressure of gas flow and direction do play a role on the final quality of down-facing surfaces. Orienting down-facing surfaces parallel to the gas flow gives the best dimensional accuracy. While parts furthest away from the gas flow nozzles presented the least dimensional accuracy. This work also allows the future development of compensation strategies for printing parameters based on the location of the down-facing surface on the build platform as well as for considering other responses such as density, surface roughness etc.