Influence of the clearance angle on the cutting efficiency of blunt, octahedral-shaped diamonds in an active filler alloy

•No microstructural alterations by positive clearance angles.•Experimental differentiation between cutting and ploughing mechanism.•New approach for future structuring technologies for grinding and dressing tools.•Cutting force ratios up to 0.60.

For increasing the efficiency of processes with non-defined cutting edges a new approach based on an experimental study using blunt, octahedral-shaped diamond grains is presented. This approach considers the orientation of the flank face towards the cutting direction and enables the determination of the ploughing share caused by negative clearance angles. Positive clearance angles enable an efficient removal of the ductile work piece material while cutting force ratios up to 0.68 were achieved in this study. This amelioration of the efficiency increase during the material contact caused by positive clearance angles is characterised by the absence of a white layer in the subsurface zone of machined material, which could be observed when grains with negative clearance angle were applied.