Staged thermomechanical testing of nickel superalloys produced by selective laser melting

Xu, Zhengkai; Hyde, Christopher J.; Thompson, Adam; Leach, Richard K.; Maskery, Ian; Tuck, Christopher; Clare, Adam T.

Abstract

The creep performance of additively manufactured components remains an issue before additive manufacturing can be put fully implemented. In this study, Inconel 718 two-bar specimens are produced by selective laser melting and subjected to a ‘staged’ creep test. Creep test was interrupted at critical junctures and X-ray computed tomography measurements performed at various extensions of the specimen. Periodic X-ray computed tomography measurements allow, for the first time, examination of the specimens during creep testing. Evaluation of specimen performance shows the number and size of pores within the specimen increasing over time as a result of classical creep mechanisms. Location and tracking over time of weak points are performed, allowing early estimation of sample failure points. This information is valuable to selective laser melting practitioners who seek to optimise the build strategy in order to minimise in-built defects.

Citation

Xu, Z., Hyde, C. J., Thompson, A., Leach, R. K., Maskery, I., Tuck, C., & Clare, A. T. (2017). Staged thermomechanical testing of nickel superalloys produced by selective laser melting. Materials and Design, 133, 520-527. https://doi.org/10.1016/j.matdes.2017.08.009

• Journal Article Type: Article
• Acceptance Date: Aug 4, 2017
• Online Publication Date: Aug 4, 2017
• Publication Date: Nov 5, 2017
• Deposit Date: Sep 15, 2017
• Publicly Available Date: Aug 5, 2018
• Journal: Materials & Design
• Print ISSN: 0261-3069
• Electronic ISSN: 0264-1275
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 133
• Pages: 520-527
• DOI: https://doi.org/10.1016/j.matdes.2017.08.009
• Keywords: Creep; Two-bar specimen; X-ray computed tomography; Selective laser melting; Mechanical testing; Nickel superalloys
• Public URL: https://nottingham-repository.worktribe.com/output/893186
• Publisher URL: http://www.sciencedirect.com/science/article/pii/S0264127517307530
• Contract Date: Sep 15, 2017