The pronounced brittleness of hard Laves phase intermetallics is detrimental to their tribological properties at room temperature. In this study, we utilized a heterogeneous structure to engineer an ultrastrong dual-phase (Laves + B2) AlCoFeNiNb high-entropy alloy that exhibits a low wear rate (3.82×10^-6 mm³/(N·m)) at room temperature. This wear resistance in the ball-on-disc sliding friction test with the counterpart of Al₂O₃ balls stems from the activated deformation ability in the ultrafine Laves lamellae under heterogeneous interface constraints. Furthermore, as tribological stress intensifies, the surface deformation mechanism transitions from dislocation slip on the basal and pyramidal planes to a unique combination of local shear and grain rotation within the Laves phase. Our study illuminates fresh perspectives for mitigating the embrittling effect of Laves phase intermetallics under tribological loading and for the development of wear-resistant materials.

Magnesium and its alloys have such advantages with lightweight, high specific strength, good damping, high castability and machinability, which make them an attractive choice for applications where weight reduction is important, such as in the aerospace and automotive industries. However, their practical applications are still limited because of their poor corrosion resistance, low high temperature strength and ambient formability. Based on such their property shortcomings, recently degradable magnesium alloys were developed for broadening their potential applications. Considering the degradable Mg alloys for medical applications were well reviewed, the present review put an emphasis on such degradable magnesium alloys for structural and functional applications, especially the applications in the environmental and energy fields. Their applications as fracture ball in fossil energy, sacrificial anode, washing ball, and as battery anodes, transient electronics, were summarized. The roles of alloying elements in magnesium and the design concept of such degradable magnesium alloys were discussed. The existing challenges for extending their future applications are explored.