The effect of high current pulsed electron beam irradiation on microstructure and properties Cu-Fe powder metallurgical alloys

In this paper, Cu-Fe powder metallurgical alloys were firstly fabricated, and a innovative surface modification technique, high current pulsed electron beam (HCPEB), was then irradiated these Cu-Fe alloys with 5 and 10 pulses. The morphologies, microstructure and mechanical properties of the specimens both before and after HCPEB irradiation were studied. The morphologies revealed that the surface of 5-pulsed sample was melted completely, and a large amount of craters were formed. Those craters were eliminated and fused by the subsequent 10-pulsed HCPEB processing. Besides, the distribution of Fe element was fairly homogenous on the irradiated surface. Additionally, the modified microstructures consisted of refined Cu sub-grains, tiny Fe particles, Cu (Fe) solid solution and abundant defects, which played an important role in the improvement of microhardness. The HCPEB irradiated Cu-Fe samples possessed better wear resistance which was ascribed to the reduction of roughness, enhancement of hardness, and formation of lubricating film.