| Superalloys with good resistance to anti-high temperature performance, which are widely used in aerospace, nuclear power, automobile and so on, has become one of the typical materials of parts in this field. The issues such as serious work hardening and short serve life of tools emerge in the processing of high temperature alloy, tools should have capabilities such as high wear resistance and Oxidation resistance and so on when cutting superalloy.Through analyzing the present situation and existing problems in tool's life and failure mode, this paper defined an evaluation index of high temperature alloy tool's serve life, and established an evaluation system of high temperature alloy tool's serve life, and had an experimental study of high temperature alloy tool's life evaluation.Firstly, the factors affecting the tool's life are classified, and tool wear and breakage are analyzed; the evaluation index of high temperature alloy tool life have been put forward, and the evaluation index and tool wear model are established; several ways affecting processing efficiency are analyzed, and the processing efficiency model was established to provide a theoretical basis for the evaluation of the high temperature alloy tool's life.Secondly, the evaluation system of superalloy tool life is established, qualitative analysis of evaluation parameters is completed. The process to determine the weight of AHP is studied. According to the requirements of the evaluation system, the objective function is determined, the optimizing variables are selected and genetic algorithm is adopted to realize the parameter optimize parameters of tool wear.Thirdly, experimental study on the PCBN cutting superalloy GH706 is carried out. The wear form of PCBN tool is analyzed and expressions of cutting time are established. The influences of cutting parameter and tool wear on surface roughness, degree of work hardening and depth of work hardening are analyzed. The equation of tool wear about surface roughness and hardening depth is establishing.Finally, according to the selected cutting conditions and tool angle, AHP is used to determine the first-degree evaluating indicator weight of superalloy evaluation system's tool life and surface integrity weight, then the weight of surface integrity index in the system is determined.The evaluation equation of the tool life and single edge removal are regarded as objective function. The multi-objective optimization model is established based on genetic algorithm and the tool wear amounts which meet current processing conditions are got.The calculated cutting time is tool life according to the current amount of wear. |
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