The effect of laser micro-scale textured tools on the tool-chip interface performance and surface integrity during austenitic stainless-steel turning

Demand for stainless steels is rapidly increasing, especially in the oil and gas industries. Stainless steel offers a number of key advantages such as high tensile strength, toughness, and excellent corrosion resistance. However, stainless steel machining still poses some serious difficulties. At low cutting speeds, workpiece material and chips tend to adhere to the cutting tool surface, forming a built-up edge (BUE). Unstable BUE can cause tool failure and deterioration of the workpiece surface quality. However, stable BUE formation can protect the cutting tool from further wear, improving the productivity of AISI 304 stainless steel machining. In this work, a femtosecond laser was used to apply different shaped textures on the rake face of the cutting tool (square, parallel, perpendicular) to understand the effect of different texture shapes and orientations on tool-chip interface performance, BUE stabilization and process efficiency, when turning AISI 304 austenitic stainless steel with a (WC + 6%Co) cemented carbide cutting tool. It was found that: the maximum reductions of 58%, 100%, and 24% in the respective cutting force, feed force, and coefficient of friction were obtained with the square textured tool; BUE formation was lower and more stable with square textured tools, reducing flank wear by 41–78% and enhancing surface finish by 54–68% in comparison to the untextured tool; the thickness and hardness values of the heat-affected zone were lower in the workpiece machined by the tools with the square textured pattern.