He-ion Irradiation Effects on the Microstructures and Mechanical Properties of the Ti-Zr-Hf-V-Ta Low-Activation High-Entropy Alloys

Huanzhi Zhang; Qianqian Wang; Chunhui Li; Zhenbo Zhu; Hefei Huang; Yiping Lu

doi:10.3390/ma16165530

He-ion Irradiation Effects on the Microstructures and Mechanical Properties of the Ti-Zr-Hf-V-Ta Low-Activation High-Entropy Alloys

Materials (Basel). 2023 Aug 9;16(16):5530. doi: 10.3390/ma16165530.

Authors

Huanzhi Zhang¹, Qianqian Wang¹, Chunhui Li¹, Zhenbo Zhu², Hefei Huang², Yiping Lu¹

Affiliations

¹ Key Laboratory of Solidification Control and Digital Preparation Technology (Liaoning Province), School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China.
² Shanghai Institute of Applied Physics, Chinese Academy of Sciences (CAS), Shanghai 201800, China.

Abstract

High-entropy alloys (HEAs) have shown promising potential applications in advanced reactors due to the outstanding mechanical properties and irradiation tolerance at elevated temperatures. In this work, the novel low-activation Ti₂ZrHf_xV_0.5Ta_0.2 HEAs were designed and prepared to explore high-performance HEAs under irradiation. The microstructures and mechanical properties of the Ti₂ZrHf_xV_0.5Ta_0.2 HEAs before and after irradiation were investigated. The results showed that the unirradiated Ti₂ZrHf_xV_0.5Ta_0.2 HEAs displayed a single-phase BCC structure. The yield strength of the Ti₂ZrHf_xV_0.5Ta_0.2 HEAs increased gradually with the increase of Hf content without decreasing the plasticity at room and elevated temperatures. After irradiation, no obvious radiation-induced segregations or precipitations were found in the transmission electron microscope results of the representative Ti₂ZrHfV_0.5Ta_0.2 HEA. The size and number density of the He bubbles in the Ti₂ZrHfV_0.5Ta_0.2 HEA increased with the improvement of fluence at 1023 K. At the fluences of 1 × 10¹⁶ and 3 × 10¹⁶ ions/cm², the irradiation hardening fractions of the Ti₂ZrHfV_0.5Ta_0.2 HEA were 17.7% and 34.1%, respectively, which were lower than those of most reported conventional low-activation materials at similar He ion irradiation fluences. The Ti₂ZrHfV_0.5Ta_0.2 HEA showed good comprehensive mechanical properties, structural stability, and irradiation hardening resistance at elevated temperatures, making it a promising structural material candidate for advanced nuclear energy systems.

Keywords: helium bubbles; high-entropy alloys; irradiation tolerance; low-activation materials; mechanical properties.

Grants and funding

Supported by the National Key Research and Development Program of China (Nos. 2019YFA0209901 and 2018YFA0702901), Liao Ning Revitalization Talents Program (No. XLYC1807047).