Research on Wear Resistance and Corrosion Resistance of Al-11Si-5Cu-5Ni-xMn Alloys for Laser Additive Manufacturing

The development of high-performance aluminum alloy materials for automotive engine components is a significant challenge due to the harsh working conditions. A unique aluminum alloy composition was designed and Al-11Si-5Cu-5Ni-xMn（x =0,2） alloy was prepared by laser cladding technology. The microstructure, element distribution,phase composition, wear resistance and corrosion resistance of the cladding layer were investigated using advanced techniques such as optical microscopy（OM）, SEM, XRD, sliding friction wear testing machine and electrochemical workstation. The analysis reveals that the alloys are primarily composed of various intermetallic phases, including Al₃ Ni, Al₂ Cu, Al₇ Cu₄ Ni,Al₃ CuNi, Al₁₅ Mn₃ Si₂ and Al₄ Ni₃ . The alloys are prepared by laser cladding exhibit a compact structure with increased microhardness and excellent wear resistance because there is a higher number of second-phase reinforcements. The analysis of the alloy using electrochemical methods such as open-circuit potential, polarization curves, and impedance analysis shows that the addition of certain elements has decreased the corrosion resistance of the alloy. After a comprehensive analysis of the experimental results for various alloys, it is found that Al-11Si-5Cu-5Ni-2Mn alloy exhibits the best overall performance.Some key properties of this alloy are: Vickers hardness of 120.7 HV, sliding friction coefficient of 0.303, friction wear rate of 5.58 mm³/（N·M）, open-circuit potential in electrochemical corrosion of -0.616 V, corrosion potential of -0.9979 V, and the corrosion current density of 1.3234×10^-5A/mm².