Mechanical behavior and thermal activation analysis of HfNbTaTiZr body-centered cubic high-entropy alloy during tensile deformation at 77 K

SCRIPTA MATERIALIA

卷:188

Article

Eleti, Rajeshwar R.¹  Stepanov, Nikita¹  Zherebtsov, Sergey¹ 

[1] Belgorod Natl Res Univ, Lab Bulk Nanostruct Mat, Pobeda 85, Belgorod 308015, Russia

关键词: Low-temperature plasticity;    Body-centered cubic;    High-entropy alloy;    Slip trace analysis;    Activation volume;   

DOI  :  10.1016/j.scriptamat.2020.07.028

来源: Elsevier

【 摘 要 】

Plastic deformation of HfNbTaTiZr body-centered cubic high-entropy alloy (BCC-HEA) was investigated at 77 K. Tensile stress-strain curves showed strong temperature dependence of yield strength. Characteristics of dislocation slip at 77 K was analyzed using slip traces which confirmed active slip on {112} planes. The apparent activation volume (V*) suggested thermally activated kink/kink-pair nucleation at 77 K (V*similar to 7b(3)). V* values of BCC-HEA and pure Nb were nearly same at 77 K. Low-temperature plasticity of the BCC-HEA showed characteristics of pure BCC metals, suggesting chemical-complexity of HEAs may not alter the Peierls potential of a/2 < 111 > screw dislocations. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

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