Effect of hybrid texture combining micro-pits and micro-grooves on cutting performance of WC/Co-based tools

Abstract

Friction at the tool-chip interface may be reduced by introducing a lubricant into the tool-chip interface; the effectiveness of which can be enhanced by surface texturing the tool. Micro-grooves, micro-pits, and hybrid texture combining micro-pits and micro-grooves were fabricated employing laser on the rake face of carbide tools, with a view to facilitating lubricant penetrate and retention; then, solid lubricant (molybdenum disulfide) was applied to fill micro-textures to form micro-pools. In the present study, the effect of hybrid texture on the cutting performance was experimentally investigated using the hybrid-textured tools, single-textured tools, and conventional tools in dry turning pure iron tests on the numerical control lathe. The behavior of these tools was quantified in terms of the cutting forces, cutting temperature, friction coefficient at the tool-chip interface, shear angle, surface roughness of machined workpiece, chip morphology, and tool wear on the rake face. Results confirm enhanced cutting performance of hybrid-textured tools by collaborative complementation as micro-reservoir for constant lubricant replenishment of micro-grooves and micro-pits. It is suggested that the hybrid-textured self-lubricating tool is applicable to a stable dry cutting of pure iron.