Microstructure and properties of Cu-Cr powder metallurgical alloy induced by high-current pulsed electron beam

Highlights: • HCPEB irradiation was conducted on Cu-Cr powder metallurgical alloy. • The density and size of craters and Cr particles were decreased with increasing of pulses. • A large number of defects on the surface were produced by HCPEB irradiation. • The wear performance was significantly enhanced by HCPEB irradiation. The purpose of paper is to investigate the microstructure and properties of Cu-Cr alloys induced by high-current pulsed electron beam (HCPEB) irradiation. Microstructure of the alloying layer was studied by means of X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscopy (TEM). The microhardness and friction property were also tested. The microstructure reveals that craters were formed which were fused and eliminated to form flat surface with increase of the pulse number. Additionally, the inter-diffusion of Cu and Cr elements caused component homogenization of the surface melted layer. Besides, the fine grains/particles and Cu (Cr) solid solution were formed. Those factors accounted for a significant increase in microhardness. The lowest COF and wear rate were attributed to the ultrafine Cr particles in the hard Cu matrix.