Suppression of grain boundary migration at cryogenic temperature in an extremely fine nanograined Ni-Mo alloy. (15th November 2020)

• Record Type: Journal Article
• Authors: Hu, J.; Li, J.X.; Shi, Y.-N.
• Is Part Of: Journal of materials science & technology. Volume 57(2020)
• Page Start: 65
• Page End: 69
• Publication Date: 2020-11-15
• Subjects: Extremely fine nanograined metals -- Mechanically-driven grain boundary migration -- Cryogenic temperature -- Shear bands -- Solute atoms; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2020.03.048
• Languages: English
• ISSNs: 1005-0302

Abstract

Abstract: Microindentation creep tests on an electrodeposited extremely fine (4.9 nm) nanograined (ng) Ni-14.2 at.% Mo (Ni-14.2Mo) at both room temperature (RT) and liquid nitrogen temperature (LNT) demonstrated that lowering temperature retarded softening in the ng Ni-Mo alloy. The obtained strain rate sensitivity at LNT was one order of magnitude lower than that at RT. Microstructural characterization revealed that mechanically-driven grain boundary (GB) migration was greatly suppressed by lowering temperature, which might be ascribed to the presence of solute Mo atoms that significantly retarded coupled GB motion at LNT. Deformation was instead carried by shear bands.