Modeling And Experimental Research On Residual Stresses Of Machined Surface In Titanium Turning

Titanium alloy Ti6Al4V with its superior performance has been widelyapplied in various fields, the material for titanium alloy parts is mainly applied toimportant parts of the mechanism.Therefore, it is very high that the use oftitanium alloy parts performance and the surface quality requirement,such asfatigue strength and the service life of workpiece and so on. This article startswith the affect of the residual stress on the machined surface, establish theequivalent thermal-force load model of residual stress which affects themachined surface, and predicts the residual stress in machined surface oftitanium alloy, the main research work as follows:First, according to the theory of metal cutting and thermal elastic-plasticdeformation theory as the foundation, the effect of cutting heat and cutting forceon machined surface residual stress has been studied; Analysis of the cuttingforce and chip thermal load in the tool-chip interface and tool-workpiece surfacethermal distribution form, the methods of simplify the load were studied;Decomposite the cutting force of cutting process and cutting edge area of ploughforce，build the relationship among the cutting force and friction heat sourcecoefficient, cutting temperature and heat flux, and the relationship betweencutting force and equivalent stress, then set up machined surface residual stressof the equivalent thermal-force load mode.And then, it will carry out finite element simulation analysis of forcethermal load distribution of cutting process of, study the feasibility of thesimplified load; According to the results of the research,conduct a test ofequivalent load model of heat friction and residual stress; Build machinedsurface’s model of residual stress equivalent thermal load simulation, andthrough the machined surface residual stress testing experiment verify the reliability of the finite element model.Finally, to research on the influence laws of the tool wear effect on residualstress, through the analysis of tool wear morphology,study on the change ofabrasion tool shape and size has the influence on surface residual stress; Fromthe perspective of the tool wear geometry and combined with the finite elementsoftware, set up on the impact of tool wear on finished surface residual stressfinite element model, then realization of finite element modeling and analysis ofthe tool wear on the machined surface residual stress effects．...