Inconel and other nickel superalloys keep their strength at extreme heat, which is exactly what makes them punishing to machine: they work-harden fast, hold heat at the edge and chew through tooling. Success means rigid setups, sharp positive tooling, firm uninterrupted feeds (never dwell), and heavy high-pressure coolant — often ceramic tooling for roughing.
This is some of the hardest cutting there is; a stiff machine with strong low-end torque and high-pressure coolant earns its keep. See Inconel and work hardening, and value machines at The Machine Blue Book.
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