Nd:YOV4 laser surface texturing on DLC coating: Effect on morphology, adhesion, and dry wear behavior

Abstract

The surface of structural components is usually subjected to higher stresses, greater wear or fatigue damage, and more direct environmental exposure than the inner parts. For this reason, the interest to improve superficial properties of items is constantly increasing in different fields as automotive, electronic, biomedical, etc. Different approaches can be used to achieve this goal: case hardening by means of superficial heat treatments like carburizing or nitriding, deposition of thin or thick coatings, roughness modification, etc. Between the available technologies to modify components surface, Laser Surface Texturing (LST) has already been recognized in the last decade as a process, which improves the tribological properties of various parts. Based on these considerations the aim of the present research work was to realize a controlled laser texture on a Diamondlike Carbon (DLC) thin coating (about 3 m thick) without damaging both the coating itself and the substrate. In particular, the effect of laser process parameters as marking speed and loop cycle were investigated in terms of texture features modifications. Both qualitative and quantitative analyses of the texture were executed by using a scanning electron microscope and a laser probe system to select the proper laser parameters. Moreover, the effect of the selected texture on the DLC nanohardness, adhesion and wear behavior was pointed out.

Synergetic effects of surface texturing and solid lubricants to tailor friction and wear – A review

“…For DLIP, graphitization occurs only at the regions of maximum interference [192,208,210,211]. For higher fluences, which can be obtained by increasing either the energy density or the number of laser pulses, ablation dominates, thus locally removing the carbon film to generate grooves or dimples [124,228]. For DLIP, ablation occurs at the regions of maximum interference, with significantly thinner films remaining [211].…”