Wear Performance and Corrosion Behavior of Nano-SiCp-Reinforced AlSi7Mg Composite Prepared by Selective Laser Melting

It is one of the future trends to create materials in situ by laser additive manufacturing. AlSi7Mg/nano-SiCp composites were successfully in situ prepared by selective laser melting in our previous study. After adding 2 wt% nano-SiC particles, the tensile stress and strain increased to 502.94 ± 6.40 MPa and 10.64 ± 1.06%, respectively. For the first time in the present study, we systematically studied and compared the wear performance and corrosion behavior of AlSi7Mg with its composite. We conducted the ball-on-flat frictional wear test at room temperature, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and the immersion corrosion tests in 3.5 wt% NaCl solution. The results showed that composite had higher wear resistance, while AlSi7Mg was more resistant to pitting corrosion. However, the further pitting corrosion of composite was restrained because of the in situ phase nano-Al4C3 and the residual nano-SiCp.