The influence of tip shape in abrasion studied by controlled multiasperity surfaces

Abstract

The influence of abrasive tip angle, tip blunting and tip packing density on the wear rate has been studied using controlled multiasperity surfaces of silicon. The surfaces were manufactured by micromechanical etching techniques and controlled with respect to tip angle, size, radius and intertip distance. In this work, pyramidal abrasive structures were produced with three tip packing densities, two tip radii and different tip angles. Wear tests were performed in a pin-on-abrasive disk configuration with tin as abraded material. Both the abrading silicon tips and the worn tin surfaces were studied by scanning electron microscopy (SEM). The results reveal an apparently linear dependence of tip angle on the measured wear rate for both sharp and blunt tips. For sharp tips, the angle dependence of the abrasion rate is approximately linear and independent of the packing density of the tips. Blunt tips, however, give lower wear rates and also lower sensitivity to variation in the tip angle than sharp tips. Further, the sensitivity of tip angle falls with increased packing density of the tips. This paper demonstrates a novel method for fundamental studies of the effects of the abrasive tip shape on the resulting wear rates. The present study is more closely related to real abrasive and grinding processes than the frequent single tip experiments.