|About this Abstract
||2020 TMS Annual Meeting & Exhibition
||High Entropy Alloys VIII
||Unraveling Atomic-scale Lattice-distortion Strengthening of Precipitate-hardening High-entropy Alloys
||Jia Li, Haotian Chen, Yang Chen, Chao Jiang, Qihong Fang, Bin Liu, Yong Liu
|On-Site Speaker (Planned)
High-entropy alloys (HEAs) have outstanding mechanical properties at cryogenic/elevated temperatures. However, intrinsic mechanisms of strengthening in extreme environments are still not well understood. Here we report the synergistic strengthening of atomic-scale lattice distortion and precipitation in HEAs at cryogenic/elevated temperatures, to reveal severe lattice-distortion-dominated hardening behaviour. Severe atomic-scale lattice distortion of HEAs causes the curved dislocation line with kinks located at various local tensile-or-compressive stress fields, to cut more atoms, compared with pure metals. Original cause of high strengths at cryogenic temperatures is attributed to large atomic-scale lattice distortion frozen in HEAs matrix to difficultly release lattice-distortion energy by the diffusion, while at elevated temperatures due to that slow diffusion induced by lattice-distortion-generated deep stress trap along diffusion path result in relatively-stable structure of precipitates.
Keywords: High-entropy alloy; lattice distortion; precipitation strengthening; atomic simulation.
||Planned: Supplemental Proceedings volume; Planned: Supplemental Proceedings volume