|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Advances in Multi-Principal Elements Alloys X
||Composition- and grain-size-dependent hydrogen uptake and its effect on plastic deformation of face-centered cubic high-entropy alloys
||Yakai Zhao, Jeong-Min Park, Upadrasta Ramamurty, Jae-il Jang
|On-Site Speaker (Planned)
An intriguing yet overlooked issue in hydrogen effects on high-entropy alloys (HEAs) is the hydrogen uptake and its effects in the fcc HEAs having very different fractions of defects. Therefore, in this work, the effect of marked change in grain size from coarse-grained to nanocrystalline on the hydrogen absorption and plastic deformation behavior of two HEAs, viz. equiatomic CoCrFeNi and CoCrFeMnNi, were investigated. Thermal desorption analysis of the hydrogen-charged samples proved that grain boundaries act as hydrogen traps and thus largely increase the hydrogen contents in the nanocrystalline samples. The parameters for the thermally activated deformation from nanoindentation rate-jump tests suggest enhanced lattice friction by hydrogen, leading to a reduction in activation volume and thus modification of the plastic deformation processes. The results are discussed in two aspects, viz. the effect of grain size and chemical composition on the hydrogen-affected plastic deformation.
||High-Entropy Alloys, Hydrometallurgy, Mechanical Properties