High speed machining of nickel-based alloys

Abstract

The connection between rotor disc and blades in turbine applications is usually realised by complex profiled grooves. The profiled grooves are mostly manufactured by broaching processes. In compressor and fan applications, alternative cutting processes such as milling and broaching with more advanced cutting materials are already implemented. In turbine applications, where nickel-based alloys are used due to high forces and temperatures, the use of HSS-tools is still state of the art. Due to the low high temperature strength of this cutting material, cutting speeds do not exceed vc = 2-5 m/min. The use of alternative manufacturing processes for roughing therefore has a high potential. This paper presents experimental results on rough side milling of nickel-based alloys with whisker reinforced ceramics at cutting speeds up to vc = 1,500 m/min including wear behaviour and metallographic analysis. The results are compared to further alternative processes discussed to complement the broaching of profiled grooves and broaching with alternative tool grades.