Study On Irradiation Effect And Mechanical Properties Of FeCrAl And B₄C

Nuclear energy plays an important role in global energy supply and puts more stringent requirements on the performance of nuclear materials,making research on the radiation effects of nuclear materials more urgent.FeCrAI has excellent properties such as corrosion resistance,radiation resistance,high-temperature oxidation resistance,and stress corrosion cracking resistance,and is considered one of the most promising accident fuel cladding materials.B4C is a functional ceramic material with excellent properties,especially high thermal neutron absorption capacity,commonly used in the control rod materials and nuclear shielding materials of nuclear reactors.This paper studies FeCrAI and B4C.conducts He and Fe ion irradiation in the MeV energy range and above based on the Low Energy intense-highly-charged ion Accelerator Facility(LEAF)at the National Laboratory of Heavy Ion Research Facility in Lanzhou,and characterizes the microstructure using TEM and analyzes the mechanical properties using nanoindentation.Based on the physical models of Nix-Gao and other researchers.the paper explores the evolution mechanism of mechanical properties of materials under ion irradiation in both experimental and theoretical aspects.The main research content and results:Explored the structural changes and mechanical properties of FeCrAI by He ion irradiation,only a large number of black-dot defects were found in the irradiation damaged area and FeCrAI was hardened by irradiation which proved that the contribution of black-dot defects to the irradiation hardness cannot be ignored.Irradiated FeCrAl by Fe ions,it was found that a large number of small billock structures appeared on the irradiated surface,and it was found that there was segregation behavior in the structure and the hardness of the alloy decreased.The relationship between FeCrAI composition and radiation hardening was subsequently explored,and it was found that when the AI content was 4 wt%,the FeCrAI radiation hardening degree was the highest when the Cr content was 17 wt%.B4C was irradiated with different conditions of He ions and Fe ions,and it was found that the single He ion irradiation had little effect on the damage and hardness of B4C;The larger damage is caused,and the hardness of B4C is obviously reduced,and the He-Fe mixed beam irradiation has the most significant effect due to the synergistic effect.