Dimensional accuracy of titanium direct metal laser sintered parts

To address concerns regarding quality of production parts created using the Additive Manufacturing (AM) process, a study was conducted to quantify the dimensional accuracy of said parts. Fourteen AM builds were manufactured in Ti-6Al-4V material across two EOS DMLS machines (EOSINT M 280 and EOS M 290). In addition to studying the impact of machine-to-machine variability, other factors potentially impacting final dimensional accuracy were studied, including: powder state (virgin or reused); post-processing steps (heat treatment and part removal from substrate); location of part on substrate; and nominal part size. The results of the dimensional analysis showed that the individual machine itself was the dominant factor impacting dimensional accuracy. Also, a non-linear relationship between dimensional accuracy and nominal part size was identified, which would require a more complex machine calibration technique to correct.