Tribological Properties of Inconel 625 Alloy Reinforced by Biomimetic Shell-like Micro-texture with Double Texture Density Filled by SnAgCu

Abstract

Inspired by the microstructure characteristics of the seashell surface texture, Inconel 625 matrix biomimetic self-lubricating composites (IMBSC) were designed and prepared by filling solid lubricant SnAgCu in the biomimetic shell-like micro-texture of Inconel 625 alloy to improve its tribological properties. The optimum combination of texture density and self-lubricating mechanism of IMBSC were studied. The results show that the tribological properties of IMBSC are strongly dependent on the synergistic lubrication effect of SnAgCu and biomimetic shell-like micro-texture. When the groove width is 300 μm, the double texture density combination is 25 and 33%, and the groove depth is 500 μm, the IMBSC-25&33 sample has the best tribological performance, with an average friction coefficient of 0.307 and a wear loss of 0.00825 mm³. Compared with the Inconel 625 alloy, the average friction coefficient and wear loss of IMBSC-25&33 decreased by 50.7 and 97.8%, respectively. Compared with other texture densities, the IMBSC-25&33 sample with double texture density can achieve more sufficient lubrication of the worn surface. Thus, a more uniform and stable lubrication film with an appropriate thickness of 15 μm is formed on the friction contact surface, thereby improving the tribological performances of the sample. This study helps us understand the important influence of texture density on the tribological properties of IMBSC and provide a self-lubricating design strategy of friction surface for engineering application.