Surface generation via scallop overlap analysis during grinding

Abstract

Grinding is a multipoint cutting operation, which involves random arrangement of abrasives on the tool surface. These abrasives act as cutting points with each grit particle having a unique shape and size, which makes grinding a highly complex process for analytical studies. No two grinding tools manufactured under same technical specifications have the same tool topographical features. Still, not much significant technical contribution has been made to analyse the effect of grinding wheel topographical features on the characteristic of the surface ground. Therefore, in order to mitigate the huge unpredictability in the grinding responses with respect to the variations in the tool topography, an attempt has been made to analyse the process mechanics in a way so as to make the grinding process deterministic for future applications. The present study aims at analysing the correlation between the tool topographical features such as grit protrusion height and intergrit spacing on the ground surface profile. The kinematic analysis of grit-workpiece interaction is carried out by accounting for the randomness in the grit protrusion heights and intergrit spacing and the effect of process parameters such as cutting velocity and feed per grit. The trajectory of each grit travel is calculated. A method is developed to identify the ‘active grits’, thereby reflecting only their trajectories in the surface profile. A comprehensive study is carried out on all the possible interactions of the grit trajectories, which ultimately generate the surface profile. The model analyses the effect of varying range of grit protrusion height, abrasive packing and grinding process parameters on the ground surface roughness. This analysis helps in the right range of selection of tool topographical features to obtain the desired surface characteristic.