Surfaces microstructured by turn-milling: Insights in contact mechanics and coefficient of friction from experimental, numerical and theoretical analyses

Microstructured surfaces machined by turn-milling can increase the coefficient of friction (COF) by interlocking the microstructure with a softer counterpart. This study investigates their deformation behavior and contact mechanics using friction tests, numerical simulations and Persson theory. Using turn-milled specimens with four tool corner geometries, strong correlations are found between plastic deformation variables-indentation depth, deformed area-and maximum COF. The results validate numerical and theoretical methods for non-conventional surfaces. Key findings suggest optimizing microstructures with high, narrow features to increase shear surfaces and indentation depth. Linear adhesive friction models prove inadequate and shear and ploughing approaches are required to adequately evaluate the frictional performance of turn-milled microstructures. • Analyzed various turn-milled microstructures for their friction-enhancing properties • Elasto-plastic contact mechanics study to evaluate deformation of microstructures • Establish the correlation between excessive deformation and transmittable force