Chip formation, cutting temperature and forces measurements in hard turning of Gcr15 under the influence of PcBN chamfering parameters

Hard turning is a key technology for difficult-to-cut materials with high precision and efficiency. However, the turning of GCr15 hardened steel leads to elevated cutting temperature and forces even at very low cutting parameters. Therefore, cutting parameters, tool geometric parameters, and cooling mediums are generally used to improve the machinability of such hard materials. This research aims to investigate the hard turning of GCr15 by varying the chamfering angle and chamfering width of polycrystalline cubic boron nitride (PCBN) at constant cutting conditions. The workpiece material and PCBN tool parameters were designed and modeled using 2D simulations using DEFORM®. Through simulation analysis and experimental research, the cutting force, cutting temperature, and the development of saw-tooth chips were studied and compared. The results achieved from experiments and simulations are very close with a maximum error of less than 5% for cutting forces and 6.3% for cutting temperatures. It is important to mention that 2D Finite Element Modeling (FEM) of hard turning is effective and efficient to forecast and measure the cutting temperature.