Investigation on tribological properties of leaf-vein-inspired bionic textures on cemented carbide tool surfaces

Regarding the lubrication failure and exacerbated friction/wear issues encountered when carbide tools are used in high-speed cutting of titanium alloys, this study proposes a surface texturing design methodology—featuring fractal geometric characteristics and based on the bionic principles of leaf venation. A theoretical model of hydrodynamic lubrication for the fractal leaf-vein texture was established, revealing the regulatory mechanism by which the fractal topological angle modulates the pressure distribution of the lubricant film and the fluid transport behavior. The leaf-vein-inspired bionic textures were fabricated using femtosecond laser machining technology. Multiphysics coupling simulations were performed using FLUENT software, elucidating the structure–property relationship between the texture morphology and the dynamic characteristics of the lubricant film. Friction and wear experiments, accompanied by microscopic analysis, demonstrated that at a fractal topological angle of 45°, the average lubricant film pressure is increased by 37%; in the reciprocating friction and wear test, the wet friction coefficient of this textured surface (with a fractal topological angle of 45°) was 17% lower than that of the non-textured surface (from 0.246 to 0.206). This work provides theoretical underpinnings and a technical foundation for the engineering application of biomimetic functional surfaces in the field of precision manufacturing.