Reconstruction and analysis of surface topography of micro-indented surface texture by chi-square function

During surface texture micro-indentation processing, the texture around the contact area will form protrusions. The morphology of these protrusions can change the actual contact area of the contact surface and affect the functional surface. To accurately describe the morphology of surface texture protrusions during the micro-indentation process, scaled chi-square functions are proposed to fit and further analyze their morphology. By simulation, the surface protrusion curve is generated by the micro-indenter head in different materials and depths. The scaled chi-square function is used to fit the extracted curves, and the fitted n value is used as an important characteristic parameter of the protrusion morphology. The study shows that the morphology of the protrusions is related to the material’s elastic modulus, yield strength, power law hardening exponent, and forming depth. Based on our results, it is convenient to judge the highest position and maximum height of the protrusions. The research findings will aid in the holistic design of micro-indentation surface textures, predicting their morphology, and selecting appropriate processes, while also being relevant for evaluating material performance post-micro-indentation with broad application prospects.