The Influence of Iron in Minimizing the Microstructural Anisotropy of Ti-6Al-4V Produced by Laser Powder-Bed Fusion

Simonelli, Marco; McCartney, David Graham; Barriobero-Vila, Pere; Aboulkhair, Nesma T.; Tse, Yau Yau; Clare, Adam; Hague, Richard

Abstract

There remains a significant challenge in adapting alloys for metal based Additive Manufacturing (AM). Adjusting alloy composition to suit the process, particularly under regimes close to industrial practice, is therefore a potential solution. With the aim of designing new Ti-based alloys of superior mechanical properties for use in laser powder-bed fusion, this research investigates the influence of Fe on the microstructural development of Ti-6Al-4V. The operating mechanisms that govern the relationship between the alloy composition (and Fe in particular) and the grain size are explored using EBSD, TEM and in-situ high-energy synchrotron X-ray diffraction. It was found that Fe additions up to 3 wt% lead to a progressive refinement of the microstructure. By exploiting the cooling rates of AM and suitable amount of Fe additions, it was possible to obtain microstructures that can be optimized by heat treatment without obvious precipitation of detrimental brittle phases. The resulting microstructure consists of a desirable and well studied fully laminar α+ β structure in refined prior-β grains.

Citation

Simonelli, M., McCartney, D. G., Barriobero-Vila, P., Aboulkhair, N. T., Tse, Y. Y., Clare, A., & Hague, R. (2020). The Influence of Iron in Minimizing the Microstructural Anisotropy of Ti-6Al-4V Produced by Laser Powder-Bed Fusion. Metallurgical and Materials Transactions A, 51, 2444–2459. https://doi.org/10.1007/s11661-020-05692-6

• Journal Article Type: Article
• Acceptance Date: Feb 4, 2020
• Online Publication Date: Mar 2, 2020
• Publication Date: 2020-05
• Deposit Date: Feb 28, 2020
• Publicly Available Date: Mar 2, 2020
• Journal: Metallurgical and Materials Transactions A
• Print ISSN: 1073-5623
• Electronic ISSN: 1543-1940
• Publisher: Springer Verlag
• Peer Reviewed: Peer Reviewed
• Volume: 51
• Pages: 2444–2459
• DOI: https://doi.org/10.1007/s11661-020-05692-6
• Keywords: Mechanics of Materials; Condensed Matter Physics; Metals and Alloys
• Public URL: https://nottingham-repository.worktribe.com/output/4051644
• Publisher URL: https://link.springer.com/article/10.1007/s11661-020-05692-6