Reversed strength-ductility relationship in microstructurally flexible high entropy alloy. (September 2018)

• Record Type: Journal Article
• Authors: Nene, S.S.; Frank, M.; Liu, K.; Sinha, S.; Mishra, R.S.; McWilliams, B.; Cho, K.C.
• Is Part Of: Scripta materialia. Number 154(2018)
• Page Start: 163
• Page End: 167
• Publication Date: 2018-09
• Subjects: Strength -- Ductility -- Strain-induced transformation -- Twinning -- High entropy alloy; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2018.05.043
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: Conventional high strength alloys lack ductility due to lower work hardening and early onset of damage nucleation. To overcome this deficiency, high entropy alloys (HEAs) enjoy the benefit of metastability of phases to tune the deformation mechanisms for engineering strength and ductility. Inspired by this, here we present friction stir processed Fe40 Mn20 Co20 Cr15 Si5 HEA with ultrafine face centered cubic (f.c.c.) γ grains embedded in a refined hexagonal closed packed (h.c.p) ε matrix. Transformation of γ grains and twinning in ε matrix triggered uniform strain partitioning among these phases and sustained work hardening during deformation thereby reversing the conventional strength-ductility trade-off. Graphical abstract: Unlabelled Image