Effect of pretreatment parameters on cobalt removal and surface roughness of tungsten carbide prior to diamond coating

Abstract

Cobalt removal and surface roughness substrate are important parameters to determine the quality of diamond coating. Various methods are adopted to solve this problem and one of them is by using chemical pretreatment. In this present work, an attempt is made to study the effect of pretreatment parameters namely temperature and time on cobalt removal and surface roughness of tungsten carbide. Full factorial experimental design followed by Response Surface Methodology (RSM) is employed in this study to plan and analyze the experiment. The surface roughness Ry and Rz, and cobalt removal are the independent response variables. Empirical models are successfully developed to predict amount of cobalt removal and surface finish of the substrate after single step etching process. Experimental results show that the temperature is the most significant factor followed by the etching time for predicted surface roughness Ry while for surface roughness Rz, the temperature and time2 are found to be the most significant factors. Whereas for interaction of time and temperature is not significant to influence Ry. It is only significant to determine Rz and cobalt removal.