Synergistic regulation mechanism of bionic structure and poly (vinylsulfonic acid) sodium (PVSNa) coating for high load bearing lubrication

A low friction coefficient and high bearing capacity can improve the service life of implants in the human body. In this study, the surface performance was improved by coupling the structure with the material. The bionic structure was obtained on the titanium alloy (Ti6Al4V) surface by chemical etching. The mechanical properties of Ti6Al4V with bionic structure were investigated by tribological experiments with different stresses. An interesting phenomenon was found that the friction coefficient of etched surface decreased with the increase of the stress, indicating that bionic structure can effectively improve the stability of Ti6Al4V surface bearing capacity. A poly (vinylsulfonic acid) sodium (PVSNa) coating was further fabricated on etched Ti6Al4V to obtain low friction. During the sliding process, PVSNA molecules were continuously added from the bionic structure to the surface through friction force for lubrication. The synergistic regulation of bionic structure and PVSNa coating made Ti6Al4V surface obtain low friction and high bearing capacity stability. This study can serve as a guide for the design of low friction and high bearing capacity stability.