Investigation on work hardening phenomenon in turning Inconel 718 with chamfered inserts considering thermal-mechanical loads

摘要

Work hardening layer on and beneath the machined surface is one of the key factors that affects the performance and service time of the final component. However, the mechanism of the work hardening generation and its behavior are still great challenges and open issues to the academic and industry. In this paper, an investigation of the work hardening layer generated by chamfered tools is conducted based on the simulation and experimental study with the consideration of cutting force and temperature. Series of cutting tests and simulations using various edge preparation and feedrate are conducted to obtain the cutting forces, temperature and micro hardness profiles. Then, models for cutting force prediction and temperature simulation are used to reveal the generation of thermal-mechanical loads during the cutting operation. The effect of cutting edge preparation and feedrate on the generation of cutting force, temperature and work hardening was studied. The results indicate that the depth of work hardening layer can achieve to more than 60 μm under the given cutting conditions with chamfered tools. The role of feedrate and chamfer length playing in the generation of work hardening behavior in machining Inconel 718 was also discussed in the paper.