Study on thermal shock irradiation resistance of CoCrFeMnNi high entropy alloy by high intensity pulsed ion beam

Lisong Zhang,Gennady E Remnev,Xiaona Li,Eryang Lu,Xianxiu Mei,Younian Wang,Xiaonan Zhang,Vladimir V Uglov,Sergey K Pavlov,Xingzhong Cao,Na Li

doi:10.1016/j.jnucmat.2021.153413

Abstract

In recent years, high entropy alloys (HEAs) have attracted significant attention due to their excellent physical, chemical, mechanical properties, and good irradiation resistance, thus are considered as potential candidates for fission and fusion structural applications. CoCrFeMnNi HEA was irradiated by high intensity pulsed ion beam (HIPIB) to investigate the effects of thermal shock irradiation on its microstructure, surface morphology and mechanical properties. It was found that CoCrFeMnNi HEA maintained the face-centered cubic single-phase structure after HIPIB irradiation. The ion beam effect of irradiation produced numerous defects such as vacancies and stacking faults within the range of carbon ions. While the thermal effect reduced vacancy concentration beyond the ion range by promoting the recombination of vacancies with interstitials, and decreased the nano-hardness of CoCrFeMnNi HEA. The thermal effect and shock wave effect promoted the migration of vacancies and formed defects such as stacking faults etc. far beyond the ion range in CoCrFeMnNi HEA. Because of the very compositional complexity, the high-level chemical disorder and local lattice distortion of CoCrFeMnNi HEA, the lattice parameter was almost unchanged after HIPIB irradiation. Even if the temperature reached the melting point of CoCrFeMnNi HEA, there was no crack on the surface after surface remelting and rapid cooling. CoCrFeMnNi HEA showed good thermal stability and thermal shock irradiation resistance.

Highlights

The development of advanced fission and fusion reactors depends largely on the stability performance of structural materials in extreme environments such as high temperature, high stress and strong irradiation damage [1,2]
The simulation of CoCrFeMnNi high entropy alloys (HEAs) irradiated by high intensity pulsed ion beam (HIPIB)
CoCrFeMnNi HEA with single-phase face-centered cubic (FCC) structure was irradiated by HIPIB to investigate the effects of thermal shock irradiation on its microstructure, surface morphology and mechanical properties

Summary

Introduction

The development of advanced fission and fusion reactors depends largely on the stability performance of structural materials in extreme environments such as high temperature, high stress and strong irradiation damage [1,2]. It is one of the earliest HEA systems which used in irradiation research [11,12], and shows good irradiation resistance, such as promoting defect recombination [12], inhibiting irradiation-induced swelling [11] and segregation [13], defect accumulation [14] and He bubble growth [15], etc. CoCrFeMnNi HEA was irradiated by HIPIB to study its microstructure, surface morphology and mechanical property response under thermal shock irradiation. It provided the theoretical data reference for the selection and research of structural materials in nuclear devices

Experimental

The simulation of CoCrFeMnNi HEA irradiated by HIPIB

J/cm2, 3 pulses, respectively

Conclusion

Declaration of Competing Interest