FEM and statistical-based assessment of AISI-4140 dry hard turning using micro-textured insert

Abstract

AISI-4140 is a hardenable cold work tool steel widely used in metal cutting operations due to its superior strength and heat treatment capacity. During the dry hard turning of AISI-4140 steel, high cutting temperatures are generated in the tool-chip interface due to friction. Micro-textured tools are thought to improve cutting performances in dry hard turning. The motivation is that the more reducing the chip-tool interface area, the more decreasing the friction there. Therefore, the micro-textured tools can be helpful in all metal cutting applications. This study compared the effects of micro-grooved textures at different sections on either coated or uncoated inserts according to the cutting forces and interface temperatures using FEM and Grey Relation Analysis. Experimentally calibrated FEM simulations and a statistical approach have been built. Besides the general positive sense of the micro-textured tools' effects on machining performances, this study revealed a different unexpected nuance for dry hard turning of AISI-4140 with textured tools according to the design of simulations. Where textures grooved on rake face or flank face below nose radius textures, texture sections, or relationship with coatings was found to be independent for the dry hard turning of AISI-4140 in consideration of cutting temperature and resultant cutting force. It was found that the textured tools were not statistically significant contrary to expectation. The textured tools may not be the exact solution for all machining conditions.