Microstructure and mechanical properties of NiCoCrAlY laser cladding coating after high-current pulsed electron beam irradiation.

Surface modification of laser cladding coating NiCoCrAlY was carried out by high-current pulsed electron beam irradiation. The microstructure of the NiCoCrAlY coating after irradiation was studied by XRD and SEM. The results showed that the NiCoCrAlY cladding layer displays slip and a nanocrystalline structure following high-current pulsed electron beam irradiation. The high-density slip structure affects the residual stress on the surface of the melted coating, resulting in a change of the phase structure. The mechanical properties of the NiCoCrAlY coating were studied using a Vickers micro-hardness tester and a straight-line-reciprocating dry sliding wear tester. The results showed the average microhardness of the melted coating increased by 9%, and the average wear coefficient decreased by 33.7% after five electron beam irradiations. [ABSTRACT FROM AUTHOR]