Cutting Performance of Coated Cemented Carbide Tool in Driven Rotary Cutting of Hardened Steel

Abstract

Recently, cutting has replaced grinding in the finishing process for hardened steel. However, tool damage is a major problem in high-efficiency operations that use high-speed cutting and high-feed rate conditions rather than more conventional cutting conditions. Therefore, a new cutting technique that can realize high-efficiency cutting is desired. In our previous study, the processing efficiency was improved three to five times compared with conventional hardened steel cutting by driven rotary cutting. Furthermore, to attain high efficiency, the resistance of the tool material to wear and oxidation must be improved. In this study, the cutting performance of tools with an Al-rich coating, which improves oxidation resistance, is investigated for high cutting speed applications. In the present experiments, the flank wear of the Al-rich tool was less than 40 μm at a high cutting speed of 2.51 m/s, even for a cutting length of 10.0 km. Additionally, the Al-rich tool wear advanced progressively without flaking. In contrast, the conventional TiAlN-coated tools exhibited serious failure at cutting lengths of 3.0 km. It is thought that the difference in the oxidation resistance of the two tools influenced the cutting performance. Therefore, the tool with the Al-rich coating can operate with a high efficiency even at high cutting speeds.