As prosperous in automobile and aerospace industries, the competition in machining industry is getting fierce. The requirements for product lie on not only the improvement of the quality, but also the processing speed. The Nickel based superalloy can maintain a very good strength under highly elevated temperature, so it is wildly applied to the components and parts which need to resist to high temperature, such as blades of aircraft turbine engines, rotors, turbine parts for nuclear power plants, heat exchangers, reciprocating engines, heat-treating equipments, liquid rockets, space vehicles and equipments for chemical and petro chemical industries. Nevertheless, Nickel based superalloy’s high strength, low thermal conductivity and working hardening will lead to a short cutting tool life and low efficiency in machining. At the same time, AISI4340 is also widely applied to processing parts for gears, piston, automobiles and machines.

Abstract. Nickel-base superalloy is a special super heat resistant alloy developed by U.S in 1970s. It is mainly applied to turbine parts as well as high-temperature components. Nickel-base superalloys exhibit an excellent high strength, low thermal conductivity and creep resistance as well as work hardening. It is the most difficult to be machined with high-speed cutting among different sorts of high-temperature superalloys and is a material presenting multifold challenges for machining. The purpose of this study aims at the machinability of Nickel-base alloys. Engineering statistical analysis was employed to observe the cutting speeds, feed rates and surface roughness at first place. The researcher further applied the half-normal probability plot (HNPP), Pareto analysis and ANOVA to identify the cross effects and probed into the characteristics of Nibase alloy.