Effect of electromagnetic stirring frequency on tribological performance and corrosion resistance of Al-Sn bearing alloy

The Al-Sn bearing alloy was prepared by electromagnetic stirring (EMS) technique, and the effect of stirring frequency on tribological performance and corrosion resistance of Al-Sn bearing alloy was studied. The samples were subjected to tribological experiments and electrochemical tests. The microstructure of the sample was observed by an optical microscope, the wear surface and corrosion morphology were observed by a scanning electron microscope (SEM), the 3D morphology and wear volume of the wear mark were measured by a white light interference microscope, and the composition of corrosion product film was analyzed by X-ray photoelectron spectroscopy (XPS). The microstructure shows that when the stirring current is 60 A and the stirring frequency is 30 Hz, the electromagnetic force has a strong refining effect, and the crystal grains are fine and uniformly distributed throughout the sample. With the increase of the stirring frequency, the wear surface becomes smoother, and more wear debris adhesion phenomenon appears, showing better friction performance. The application of EMS changes the alloy microstructure, which in turn improves the distribution of Sn and enhances the tribological properties. At the same time, the sample with EMS generates a dense corrosion product film in the later stage of immersion, which has good corrosion resistance.