Performance analysis of tools with rake face textures produced using wire-EDM in turning AISI4340

Tool–chip interface friction significantly affects the machining characteristics like cutting forces, machining temperature, tool wear, and surface finish. Structuring the tool rake face using micro-textures is a recent method adopted to reduce tool–chip interface friction. The effect of varying the depth of these rake face micro-textures on the machinability of AISI4340 is studied. Textures of uniform width but with depth varying from 60 to 145 μm are created on the tool rake face using wire-EDM process perpendicular to the chip flow direction. The performance of these tools is compared with a non-textured tool in terms of cutting forces, cutting zone temperature, flank wear, chip trace area and surface finish. It is found that by optimizing the texture depth, it is possible to get improved performance from the cutting tool for the same machining conditions as compared to a non-textured tool. Further, it is found that for all the tools, the chip morphology changes during each pass from regular, closely curled helix at the beginning of the pass to randomly coiled chips at the end of the pass length with simultaneous increase in temperature.