On the interplay of internal voids, mechanical properties, and residual stresses in additively manufactured Haynes 282

• Published in: Additive manufacturing 2023-08, Vol.75 (C), p.103749, Article 103749
• Main Authors: Lim, Bryan, Nomoto, Keita, Clarke, Amy J., Babu, Sudarsanam Suresh, Primig, Sophie, Liao, Xiaozhou, Breen, Andrew J., Ringer, Simon P.
• Format: Article
• Language: English
• Subjects: Boundary conditions; Electron beam powder bed fusion; Nanoindentation; Neutron diffraction; Superalloy
• ISSN: 2214-8604; 2214-7810
• DOI: 10.1016/j.addma.2023.103749

Complex geometries and topology optimisations for weight and materials savings are leading drivers for the additive manufacturing of Ni-based superalloys through electron beam powder bed fusion (PBF-EB). However, there is a marked departure in these geometrically complex components with respect to the thermal signatures understood in commonly studied prismatic PBF-EB test coupons. This often results in unaccounted site-specific microstructure-property variations in complex PBF-EB builds. Here, the effects of topological changes, such as intentionally engineered internal voids, on the mechanical performance of an as-fabricated Haynes 282 monolith is revealed. The internal voids serve as representative physical models for changing thermal boundary conditions with build height. Complementary local nanoindentations, multi-scale microscopy, and residual stress measurements were used to understand the mechanisms behind geometry-structure-property relationships. The results highlight the effectiveness and influence of changing thermal conditions on the local mechanical property response of PBF-EB Haynes 282.