Specific Material Removal Rate Calculation in Five-Axis Grinding

Abstract

Specific material removal rate (MRR) q′ was calculated for five-axis grinding in a virtual machining simulation environment (VMSE). The axis-symmetric tool rotational profile was arc-length parameterized. The twisted grazing curve due to the concurrent translation and rotation in every move was modeled through an exact velocity field and areal MRR density q″, positive in the front of the grazing curve on the tool surface. Variation of q′ and equivalent chip thickness h within the instantaneous engagement contour were deduced from q″. Illustrative results with a five-axis impeller blade finishing simulation are shown. The results were benchmarked against an average q′ calculated from the instantaneous MRR from the VMSE. As a function of time, maximum chip thickness hmax within the extents of contact along the tool profile in every move showed more isolated peaks than corresponding qmax′. Maximum cumulative material removed per unit length Qmax′ along the tool profile from all the moves was calculated to predict axial location of maximum risk of cutter degradation. Qmax′ and hmax are useful metrics for tool path diagnosis and tool wear analysis.