Effect of Crystallographic Orientation on Cutting Forces and Surface Quality in Diamond Cutting of Single Crystal

As the depth of cut in ultraprecision machining is usually less than the average grain size of a polycrystalline aggregate, cutting is performed within a grain. Single crystals are known to be highly anisotropic in their physical and mechanical properties. In this paper, the effect of crystallographic orientation of the substrate material on cutting forces and surface quality in diamond cutting of single crystal copper and aluminium has been studied. Experimental results show that the crystallographic orientation of the workpiece material exerts a large influence on the cutting force and surface roughness. The crystallographic nature of cutting force variation was analyzed based on a microplasticity model. Analytical results compare well with the experimental data. Measures for minimizing the cutting force variation and hence improving the machined surface quality were discussed.