Changes in Contact Angles on Miller Creek Granite with Different Grades of Polishing Grits

Abstract

This paper presents the effects of different polishing levels on direct contact angle measurements on the surface of a granite aggregate specimen utilizing a sessile drop device. Contact angle measurements were performed on the rough surface of the specimen and also after each polishing stage using different grades of silicon carbide and aluminum oxide grits. The sessile drop tests were conducted on the same locations on the surface of the specimen after each polishing level and the behavior of the contact angles was observed. The results indicate that, as the surface roughness decreases with polishing, the standard deviation of the contact angle test results becomes smaller indicating consistency in contact angle measurements. The contact angles also decrease with increase in the smoothness of the specimen surface with polishing.