Microstructure and mechanical properties of two novel scrap tolerant Al₆₅Cu₁₀Mg₁₀Si₁₀Zn₅ and Al₈₀Cu₅Mg₅Si₅Zn₅ high entropy aluminum alloys

The microstructure and mechanical properties of two novel Al₆₅Cu₁₀Mg₁₀Si₁₀Zn₅ and Al₈₀Cu₅Mg₅Si₅Zn₅ high entropy aluminum alloys were studied. The alloys were developed from predominantly scrap materials by high pressure die casting route. The microstructure of the alloys revealed a complex conglomerate of phases consisting of α-Al matrix reinforced with Al₂Cu and Q-phase compounds. In terms of mechanical properties, the alloys exhibited low plastic deformation and high strength at room temperature, and increased plasticity up to 15.3% with high strength up to 317 MPa at 200 °C. The hardness value was in the range of 223 HV to 271 HV, which is three times higher than that of commercial Al alloys. The wear rate of Al₆₅Cu₁₀Mg₁₀Si₁₀Zn₅ and Al₈₀Cu₅Mg₅Si₅Zn₅ alloys was compared with that of a commercial AlSi9Cu3(Fe) and AlSi10MnMg alloys, proving the superior wear resistance of the developed alloys. Finally, the possible wear mechanisms for each alloy were proposed. Overall, the results suggest that these novel high entropy aluminum alloys have promising mechanical and wear properties, making them suitable for various industrial applications.