Anisotropic Dry Sliding Friction and Wear Properties of a Novel Stainless Steel/ZA8 Alloy Interpenetrating Phase Composite Produced by Squeeze Casting

Abstract

Novel interpenetrating phase composites (IPCs) were produced by infiltrating ZA8 alloy into sintered 304 stainless steel fiber preforms through squeeze casting. Microstructural characteristics and dry sliding wear behavior of the IPCs at room and elevated temperatures under different applied loads were investigated. The results indicate that the microstructures and wear behavior of the IPCs exhibit anisotropy. The IPCs have better wear resistance properties and lower friction coefficients in the longitudinal direction compared to the radial direction. Compared with the unreinforced alloy, the composites exhibit lower friction coefficients at both room and elevated temperatures, and the wear rate of the IPC is higher at room temperature and significantly lower at 120 °C. The friction coefficients and wear rates of the IPCs first decrease and then increase with increasing fiber fraction. The IPC with 35.98 vol% has the best wear resistance. For the IPCs, a higher applied load leads to a higher friction coefficient and wear rate. The predominant wear mechanisms for the ZA8 alloy are delamination wear, which becomes more severe with increasing applied load at room temperature, and plastic deformation and adhesive wear at 120 °C, and the IPCs show predominant abrasive (ploughing) wear and slight delamination wear. Abrasive wear becomes more severe for a too high fiber fraction at both temperatures.