Interfacial microstructure and mechanical properties of 2124 aluminum alloy reinforced by AlCoCrFeNi high entropy alloy

Using the AlCoCrFeNi high entropy alloy to enhance 2124 aluminum alloy composites is an effective way to solve its application limitations in friction and wear. In this study, the composites were prepared by mechanical alloying and spark plasma sintering. The results show that the diffusion layer was formed at the interface between high entropy particles and the matrix, and there were dislocations and significant lattice distortions near the interface. In addition, the friction coefficient (0.399) and wear rate (7.05*10−4mm3 N−1 m−1) of the composites were lower than the 2124 aluminum alloys. Moreover, the yield strength, tensile strength and compressive strength of composites were 396.2 MPa, 498.3 MPa, and 560.5 MPa, respectively. And the yield strength of the composite was almost 2 times more than that of AA2124. This work discussed the effect of interface on mechanical properties and explain the formation of diffusion layer. The present study provides a strategy to solve the lack of wear resistance and strength of composites.