Experimental investigations and kinematic simulation of single grit scratched surfaces considering pile-up behaviour: grinding perspective

Abstract

Scratch tests are useful techniques to gain insight into the material removal mechanism of abrasive machining processes. In most of the scratch tests, uncut chip thickness value is either constant or varies from zero to maximum. However, in abrasive machining processes, uncut chip thickness value ranges from either zero to maximum or vice versa. Moreover, regular scratch tests are conducted at very low speeds, in which either the indenter or the workpiece is stationary. Because of these limitations, the knowledge obtained from the existing scratch test results is not valid for most of the abrasive processes. Hence, in this paper, the influence of chip thickness variation, speed ratio, and depth of cut on the pile-up behaviour of AISI 1015 steel and 2017A-T4 aluminium alloy surfaces were investigated. The workpiece having the comparable thermal diffusivity value with the grit has shown a significant difference in its pile-up behaviour. Through a better understanding of chip thickness influence on pile-up ratio, a mathematical model was developed for kinematic simulations. Using the developed model, kinematic simulations were done to visualise the scratch surface topography and material pile-up by considering the grit trajectory path and chip thickness variation. Finally, simulated surfaces were compared with the experimental results to show the proposed method applicability.