Soundarapandiyan, G;
Johnston, C;
Khan, RHU;
Leung, CLA;
Lee, PD;
Hernández-Nava, E;
Chen, B;
(2021)
The effects of powder reuse on the mechanical response of electron beam additively manufactured Ti6Al4V parts.
Additive Manufacturing
, 46
, Article 102101. 10.1016/j.addma.2021.102101.
Preview |
Text
Leung_1-s2.0-S2214860421002669-main.pdf - Accepted Version Download (2MB) | Preview |
Abstract
High cost of metal powders has increased the demand for recycling of unmelted powder in electron beam powder bed fusion additive manufacturing process. However, powder characteristics are likely to change during manufacturing, recovery and reuse. It is important to track the evolution of powder characteristics at different stages of recycling to produce components with consistent properties. The present work evaluates the changes in Ti6Al4V powder properties during manufacturing by characterising powder particles at different locations in the powder bed; recovery and reuse, through evaluating the effects of the powder recovery system and sieving for 10 build cycles. Heterogeneous powder degradation occurred during manufacturing with the particles closer to the melt zone showing higher oxygen content and thicker α laths with β phase boundaries. Most of them had a hard-sintered and agglomerated powder morphology in contrast to particles at the edges of the powder bed. Recovery and reuse resulted in a refined particle size distribution, but only marginal change in powder morphology. The increased oxygen caused a slight increase in the yield and tensile strengths of the build. The effect of powder reuse on material elongation, hardness and Charpy impact energy was negligible. The high cycle fatigue performance deteriorated with reuse due to the increased lack-of-fusion defects. This might be attributed to the voids formed in the powder bed due to decrease in the number of fine particles coupled with an increase in the number of high-aspect ratio particles.
| Type: | Article |
|---|---|
| Title: | The effects of powder reuse on the mechanical response of electron beam additively manufactured Ti6Al4V parts |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1016/j.addma.2021.102101 |
| Publisher version: | http://dx.doi.org/10.1016/j.addma.2021.102101 |
| Language: | English |
| Additional information: | This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions. |
| Keywords: | Additive manufacturing, Electron beam powder bed fusion, Powder reuse, Powder characteristics, Build properties |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Mechanical Engineering |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10129464 |
Archive Staff Only
 |
View Item |
