Study On Simulation Technology In Machining Of Titanium Alloy Thin-walled Parts

With the development of aerospace science and technology, the titanium alloy thin-walled part isused increasingly as its compact structure, high strength and good mechanical properties. Due tosophisticated shape and poor stiffness, the machining accuracy is easily affected by deformationwhich generates in the process of clamping and cutting. To improve the machining accuracyeffectively, the titanium alloy thin-walled part with irregular surface is applied to do research onoptimization of clamping plan, synchronous optimization of clamping force and cutting parametersand compensation of cutting path. The main research is as follows:1) Fixture is designed for surface machining of the titanium alloy thin-walled part with irregularsurface. Ancillary shoring with pressure sensor is design to enhance the stiffness of thin-walled part tocontrol the deformation of clamping. FEM method is applied to analyze the clamping deformation.Optimization of clamping force and the position of ancillary shoring is carried out to minimize theclamping deformation of thin-walled part. Experiment is carried out to validate the correctness andapplicability of the model of clamping deformation forecast.2) Cutting force model which is fit for actual machining condition is obtained by designingorthogonal experiments and doing regression analysis. Based on the method of ABAQUS, the modelof cutting deformation prediction is established. The impact of cutting path and cutting parameters onmachining deformation is analyzed. Experiment is carried out to validate the correctness andapplicability of the model of cutting deformation forecast.3) In order to reduce the machining deformation, synchronous optimization between clampingforce and cutting parameters is carried out. Based on the method of genetic algorithm and finiteelement analysis, optimization model is established to obtain optimal value of clamping force andcutting parameters at every cutter location.4) According to different requirements of compensation, theory of global compensation and localcompensation is analyzed. Using the method of FEM, the value of full compensation and optimalcompensation is calculated. Experiment is carried out to validate the applicability of the model of fullcompensation. In order to generate compensation program rapidly, a software based on UG/Open isdeveloped to provide friendly interface to customer.