Study On The Constitutive Model And The Cutting Process Simulating Of Super Alloy Inconel625

Super alloy Inconel625 has been widely applied in the manufacture of key components of aero engine because of its excellent comprehensive performance under high temperature conditions. However, super alloy Inconel625 is a kind of difficult-to-machine material and is prone to problems such as quick tool wear, poor surface quality and poor efficiency in the machining process. The finite element simulation based on the constitutive model is an effective way to solve the above problems. Therefore, a study on the constitutive model and the cutting process simulation of super alloy Inconel625 is carried out in this paper. The main contents are as follows:The two theoretical systems of serrated chip formation are comparatively analyzed. The critical condition and the influencing factors of the chip serrated are discussed based on the theory of adiabatic shearing. The Serrated chip formation model proposed by Komanduri is used to derive the calculation model of strain and strain rate in the adiabatic shear band.Super alloys Inconel625 sample is applied to quasi-static compression experiment and Hopkinson pressure bar experiment. The relationships of the true stress-strain are researched under different strain rate and temperature. The rules of the flow stress changing with the factors such as temperature and strain rate are analyzed. In addition, the Johnson-cook constitutive model of Inconel625 alloy is established based on the regression analysis models, and the accuracy of the model is verified. The microstructures of the original sample and compressed sample are analyzed to study the effects of strain rate and temp erature on the microstructure changes of formed samples.The two-dimensional turning simulation of the Inconel625 alloy is established in ABAQUS finite element simulation software using the experimentally obtained Johnson-cook constitutive model. The simulation results are analyzed to describe the transformation process of chip morphology and the distribution regularities of the cutting force, cutting temperature and effective plastic strain. Each stage of serrated chip formation is studied by the analysis of the formation and development process of a serrated chip segment. The variation principles of cutting force, cutting temperature and the forming reason of the serrated chip are specifically explained in each stage.Chips of different cutting parameters in the turning experiment of Inconel625 alloy are observed to analyze the evolution process of the chip formation and the influence of cutting parameters on chip ratio, tooth pitch, serrated degree and shear band inclination etc. The finite element simulat ion using the same cutting parameters is done to compare with the experimental results, and the accuracy of the simulation model can be verified.