Simulation of internal material loads caused by multiple contacts in grinding with predominantly mechanical impact

Abstract

Grinding processes and their mechanical impact on the workpiece material are mainly characterized by multiple contacts between the workpiece surface and the single abrasive grains of the grinding wheel. The numerical modeling approach presented in this work is capable of calculating internal material loads, e.g., stresses and strains during machining, for multiple contacts of abrasive grains utilizing the CEL-method. Different numbers of repeated consecutive contacts as well as varying machining parameters such as depth of cut ae and cutting speed vc are applied. The effect of different grain shapes is investigated by utilizing spherical, flat and pyramidal grains with comparable sizes. Thereby, the surface contact area is varied. The results reveal an effect of grain shape and depth of cut as well as a saturation effect of the corresponding material modifications, e.g., shown in the source stress and plastic strain depth curves, which is reached after a certain number of contacts with specific impact intensities on the workpiece surface including the particular material removal. The approach can be applied to show principle correlations between internal material loads and material modifications in grinding processes focusing on the mechanical impact on the surface integrity.