The Study Of Wear Mechanism Of PCBN Cutting Tools In High Speed Turning Of Nickel-based Superolly

The Nickel-base-superalloy GH4169 is an ideal material to make high-heat mechanical parts such as turbine blade and aero-engine thanks to its high heat resistance and high temperature chemical and physical property. However the GH4169 is confined to manufacture industry due to its poor processing performance and excessive cutting tool wear and poor machining surface quality. With the rapid development of china’s aerospace technology and the improvement and the development of high-hardness and high durable cutting tool such as the PCBN tool. In order to meet the high accuracy and fine surface quality processing requirements of Nickel-base superalloy parts, the question for how to improve the poor cutting performance of nickel-base superalloy has become a hot issue for the manufacture of aerospace industry.Therefore the mechanism of PCBN tool wears in turning the Nickel-base superalloy with high speed are taken as prime object, the cutting test and numerical analysis method and range analysis and finite element simulation are applied in order to elaborate the PCBN tool wear appearance characteristics and tool wear mechanism and chip macro microstructure. The influence rules of cutting parameter for wear mechanism are also revealed in this paper. The main research works are as follows:1) The effective tool durability, wear morphology and energy spectrum analysis. Based on the cutting test, discusse the effective tool duarblility when PCBN cutting tool under the process of high speed machining the GH4169. The influence of cutting parameter for the tool durability is elaborated and the durability experimental equation are estlabished in this paper; the chemical elements of cutting tool and tool wear condition are analyzed under the help of electronic microscopy and energy spectrum analyzer and these research provide theorical supports for mechanism of tool wear and the typical types of tool wear.2)Build prediction model of tool wear. According to the theory of tool wear and the tool wear model pretend by Archard. Deduced it and substitue empirical formula. Establish the PCBN cutting tool wear prediction model of high-speed machining of nickel-based superalloy GH4169.3) The analysis of macro and micro morphology chips. Based on the cutting test, the chips are obtained under different cutting parameter and the macro morphology are compared by using electronic microscope,the staircasing degree and staircasing frequency and saw-tooth-shaped chip edge are also investigated and provide theoretical evidence for tool wear.4) Fem simulative analysis of tool wear. Applicated Deform-3D software to build PCBN tool cutting nickel-based superalloy model in high speed. Set the different cutting parameters and simulate the cutting process. Then simulate the changes of cutting temperature and tool wear. Compared with the experimental results and verify its correctness. Using Deform-2D software to build cutting model to simulate the changes of microstructure of chip under defferent cutting parameter. The staircasing sizes of cutting chips under different cutting parameters are observed.In conclusion, the solid theoretical foundations of tool wear mechanism model for PCBN tool under high speed machining the GH4169 are laid and at the same time applicantionof PCBN tool model and the cutting performance for Nickel-based Superolly are boosted in this paper.