Evaluation of the influence of surface structure on tribological properties of the solid-liquid interface: Analytical and experimental assessment

Nowadays, multiple strategies have been suggested to improve product efficiency on the basis of risk free techniques. Owing to the vast applications of the structured surface in many industrial sectors, considerable attention has been paid by many scholars to improve the surface performance aspects by studying their solid --liquid interface characterizations. In the current study, a new technique is introduced to manufacture a functional surface with water repellency feature through grinding process. Based on the solid-liquid interface evaluations of the modified surface, by structuring the surface, the contact angle increases from 35 degrees (untreated surface) to 127 degrees for structured surface. Therefore, the reinforced surface showed hydrophobicity with a 263% improvement for a scratch area fraction more than 75%. Formation of air pads trapped in the vacant space of the scratches was the main cause to enhance contact angle for structured surface. Since air molecules have very low inclination to chemical bonding with water molecules, the water droplet did not penetrate the scratches space and contact angle enhanced. A new analytical model for predicting the solid-liquid surface property was simultaneously developed by interaction of the kinematics of the grinding technique with single diamond and the basic wettability theory of the Cassie-Baxter. Therefore, the effect of all input parameters on the output results was studied in terms of achieving the best solid-liquid interaction performance through expanded model. The optimal values were calculated and the proposed structured surface was manufactured during the grinding process. According to the value of the static contact angle measured during experimental tests (127 degrees) and its analytical value (123 degrees), less than 4% error was observed between the results, which showed the high accuracy of the equation expanded on the present work.