Research On Milling Force Modeling And Manufacturing Process Of TC4 Titanium Alloy

With the rapid development of aerospace,ship,automobile,weapon,medicine,architecture and other industries in China,titanium alloy has been highly valued and widely used in these fields because of its excellent properties.TC4 is one of the difficult-to-machine materials widely used in aerospace industry.It is of great theoretical and practical significance to study the high-speed milling technology of titanium alloy and how to improve the cutting efficiency and surface quality.In this paper,TC4 titanium alloy material is taken as the research object,and theory,simulation and experimental methods are used to study the theoretical model of high-speed milling of titanium alloy,as well as the variation of milling force and surface roughness with processing parameters and the reasonable selection of processing parameters.The main contents of this paper are as follows:(1)Based on the theory of tool contour reproduction,a geometric model of end milling plane surface is established.The effects of feed rate,feed distance,spindle rotation eccentricity and axial movement on the surface geometric morphology are studied.(2)Based on the unequal shear zone model and oblique cutting theory,a theoretical model of milling force in titanium alloy processing is established by the method of discrete-infinitesimal-integral.The distribution of shear flow stress and temperature in unequal shear zones and the influence of processing parameters on the theoretical model of milling force were studied.(3)Finite element simulation analysis of titanium alloy processing was carried out.The stress and temperature variation of different elements in circumference and axis during milling were studied.The distribution of stress field and temperature field and the generation process of cutting force were analyzed,and the influence of processing parameters on milling force and temperature was analyzed.(4)A milling force experimental platform was constructed and the milling experiments of titanium alloy were carried out,which verified the correctness of the theoretical model of milling force and the accuracy of the finite element model.The rule of surface roughness varying with processing parameters was studied by using single factor test data.Based on orthogonal test data,an empirical model of surface roughness was established by least square fitting.(5)Based on the genetic simulated annealing algorithm,an optimization model for milling parameters of titanium alloy is established.The optimization objectives are the maximum material removal rate,the minimum surface roughness and the bi-objective function of the two together.The processing parameters are optimized by genetic simulated annealing algorithm with machine tools,cutting tools and cutting parameters as constraints.Thus,the optimal combination of processing parame ters for different objectives can be obtained.In this paper,the surface morphology,milling force and parameter optimization of titanium alloy milling process are studied,which provides a theoretical basis for further study of the surface roughness and milling force of titanium alloy processing parameters,and also provides a reference for reasonable selection of processing parameters in actual production.