Experimental verification on the influence of surface texturing on biomaterials and study of its tribological characteristics

Abstract

With the increased utilization of the surgical implants there has been a rise in the need for research in optimizing the wear resistance and enhancing its life expectancy. Artificial implants may possess surface texturing that acts as lubricating fluid reservoirs, trapping wear particles and increasing hydrodynamic pressure. As a result, the variation in dimple size and shape may significantly affect the tribological performance of the implants. Therefore, it is crucial to investigate how surface texturing affects biomaterials. A new surface texturing study on the biomaterials was proposed for enhancing the physical properties which was carried out in accordance with a theoretical analysis for understanding the distribution of stress in the textured surface of the implant. The present study focusses on 316L Stainless steel, Ultra High Molecular Weight Polyethylene (UHMWPE), Alumina, and Cobalt Chromium alloy (CoCrMo) biomaterials for experimentally verifying the effects of surface texturing. Texturing patterns were created using a laser texturing machine (Nd: YAG laser) and a pin-on-disc type machine was used to conduct wear tests on the textured and untextured components of the four biomaterials. Under typical load conditions of 70 N, friction coefficient and wear rate for the textured and untextured components of the four biomaterials were recorded. The impact of surface texturing on the tribological features was established based on the experimental findings. The test was supported by an ANSYS simulation study, which also depicts that there is a reduction in stress, which affects the coefficient of friction and eventually the wear. The Specific Wear Rate (SWR) revealed an average improvement of 59.85% between the untextured and the hexagonally textured biomaterials when compared to the results of the selected 4 biomaterials, while the Coefficient of Friction indicated an improvement of 82.66%. Thus, the laser texturing on the surface of the biological implant has a significance on the material’s property correlating to its longevity.