Effect of au-ion irradiation on the surface morphology, microstructure and mechanical properties of amorphous AlCrFeMoTi HEA coating

Abstract The amorphous AlCrFeMoTi high-entropy alloy (HEA) coating with near-equal molar ratio was successfully deposited on F/M substrate by magnetron co-sputtering technique and then was irradiated by 6 MeV Au ions with different irradiation damage doses from 10 dpa to 90 dpa. XRD, SEM, AFM, TEM and nanoindentation tests were carried out to investigate the surface morphology, microstructure and hardening effect of the coating. The results showed that the coating surface became more featureless after irradiation, where the surface roughness decreased with increasing damage doses. The crystallization phenomena occurred in amorphous AlCrFeMoTi coatings at high irradiation damage doses (45 dpa and 90 dpa), where the crystallization zone were much closer to the coating surface than the calculated peak damage region. However, the irradiation-induced crystallization did not obviously change the uniformity of elements distribution. Meanwhile, the irradiation hardening effect can be observed, and the nanohardness of the coating increased with increasing damage doses. The AlCrFeMoTi HEA coating exhibits excellent ion-irradiation resistance and has potential applications in lead cooled fast reactor. Meanwhile, this work can help us to further investigate the performance of the AlCrFeMoTi HEA coating in the coupled environment of irradiation and corrosion, and evaluate its serviceability.