High speed cutting of Inconel 718 with coated carbide and ceramic inserts

The cutting speed as a important factor influences the tool wear and the tool life when cutting nickel-based alloys with carbides and ceramics. For optimizing the cutting speed in the turning of Inconel 718, a series of tool life experiments has been carried out using various coated carbides and ceramics by means of rapid face-turning without coolant. At lower speeds (120 m/min), the tools are prone to depth-of-cut (DOC) notching, with minimal damage to the tool nose. A transition is observed at about 240 m/min, increasing the speed to 300 m/min leading to a reduction in DOC notching and an increase in nose and flank wear. The experiment results show that PVD-coated carbides KC7310 are more suitable for cutting Inconel 718 than CVD-coated carbides KC935, and ceramic inserts of KY2000 with negative rake angle and KY2100 of round type are the best choice for the high speed turning of Inconel 718. Based on the Taylor equation and the minimum production time, the optimum cutting speed was optimized in the cylindrical turning of Inconel 718 for each tested insert.