Evaluation of machinability by cutting environments in high-speed milling of difficult-to-cut materials

High-speed machining of difficult-to-cut materials generates concentrated thermal/frictional damage at the cutting edge of the tool and rapidly decreases the tool life. In this paper, the cutting environments, such as dry, flood coolant, and compressed chilly-air coolant, were investigated to improve the tool life. For this study, a compressed chilly-air system was manufactured. The experiments were performed for various hardened materials and various coated tools. The effectiveness of the developed methods on the basis of tool life was estimated. The results show that the cutting environment using compressed chilly-air coolant provided better tool life than using flood coolant or using a dry environment.