Key points are not available for this paper at this time.
An extruded Mg-10Li-5Zn-0.5Er alloy was treated by high-current pulsed electron beam (HCPEB) irradiation with different pulse counts to enhance its surface properties. The microstructures of the surfaces before and after irradiation were observed and characterized using techniques including XRD, SEM, and EDS. Additionally, tests for surface hardness, wear resistance, and corrosion performance were conducted to investigate the effects of the HCPEB treatment on the microstructural evolution and surface properties. The results demonstrated that the sample treated with 5 pulses exhibited the best comprehensive performance, characterized by the lowest friction coefficient (0.29), the minimum wear volume (3.31×10 -2 mm 3 ), the highest corrosion potential (-1.525 V), and the lowest corrosion current density (1.162×10 -6 A cm -2 ). After 20 pulses, the surface microhardness reached a maximum value of 120.4 HV under the load of 50 g (110.52 HV under the load of 25g), indicating the hardness enhancement of the modified surface layer. Firstly, the rapid remelting and solidification resulted in grain refinement, formation of a supersaturated solid solution, and dissolution of secondary phases, which contributed to solid solution strengthening and reduced micro-galvanic corrosion. Secondly, the characteristic cratered surface morphology and the introduced residual compressive stress synergistically improved the wear resistance. However, an excessive number of pulses (e.g., 20) induced microcracks, leading to deterioration in wear and corrosion performance. This study confirms that HCPEB is an effective technique for surface modification of Mg-Li-based alloys, and an optimal parameter should be set to achieve the balance among hardness, wear resistance, and corrosion resistance.
Duan et al. (Sat,) studied this question.