Defect Control And Numerical Research During The Cross Piecing Progress

As from the special materials used in the manufacture of aircraft, Titanium is wellknown as its low density, high strength, corrosion resistance and other characteristics. Thealloy has excellent performance, which use of its good mechanical properties and processperformance, made most people recognized. Titanium alloy tube is difficult to producebecause of the larger resistance to deformation hardening strong, easy to crack, etc. Withthe application of titanium in industrial promotion, Titanium alloy seam less pipe of theplastic forming process has become a hot topic in the field. In order to meet thedemanding requirements of industrial Titanium alloy tubes internal quality andperformance of the rolling process put forward higher requirements. Supported byNational Natural Science Foundation of China(51005179), the titanium tube cross piercingprocess of one factory in china as the research object, this paper did some research aboutthe thermo-mechanical coupled numerical simulation of the cross piercing process withnonlinear finite element, studied the distribution and variation of temperature, stress, strain,velocity etc. in rolling process, guessed the reason of rolling block in practical productionby the metallographic experiment and energy spectrum analysis,and analyzed the rollingprocess with finite element method based on the result.This paper built heat-mechanical coupled finite element model and simulation of thetube cross piercing process by the finite element software DEFORM-3D, the TA2materialwith a factory actual production process as the research object. studied the stress, strain,rolling temperature, rolling speed etc. Inferred the reason of the failure and the processaccording to the failure model of piercing. established the titanium tube piercing modeland steel tube piercing model accordance to the same process parameters in DEFORM-3Dplatform. Results showed that the process parameters was suitable for steel tube not fortitanium tube.Compared the stress and strain, rolling temperature, rolling speed etc. oftwo models analyzed the forces of the titanium tube piercing guide disc and found thereason of titanium tube rolling block. On this basis, did some finite element simulation bychanging a few key piercing parameters, in which simulation progressed smoothly in a certain set of parameters, while other groups failed. Thus obtained a set of reasonableparameters of titanium cross piercing process.To further study titanium tube piercing process, did metallographic experiment andenergy spectrum analysis using the titanium tube rolled block. Observed internalmicrostructure and surface quality of process waste material. Then inferred reasons ofrolling block occurred in the actual production.