Rearch On The Cold Ceformation Of TB8High-strength Titanium Alloy For Enhancing The Performance And Application

TB8high strength titanium alloy is a kind of beta type alloy, of which Americantype is β-21s. This material has excellent oxidation resistance, corrosion resistance andgood capability of plastic forming at solid solution state, and it is mainly used in theproduction of aerospace fasteners. At present, the domestic research of TB8alloy colddeformation strengthening performance reports was less, in this background to study thecold deformation aging strengthening law, characteristics and influence factors of TB8had important theoretical significance and practical application.The solid-solution state TB8was compressed in Gleeble-1500D thermal simulationtesting machine at room temperature, the strain rate is0.01,0.1,1,10s-1, respectively.Building the flow stress model of TB8and resulting data into the DEFORM simulationsoftware, extensive material database. Then according to result of the process analysisof the part model the mold structure and workpiece by Solidworks3D software. Withthe help of numerical simulation software DEFORM rigid-plastic element simulationwas done for cold extrusion forming. The effective stress and travel-load was analyzed.Do the experiment based on the analysis result. Subsequent processing the semi-finishedproducts got from experiment, the hardness testing, metallographic analysis, scanningelectron microscopy (SEM) and transmission electron microscope (TEM) weredone.This paper comparatively studied the cold forging process for reinforcement ofTB8material, connected the deformation and the grain morphology as reference of thegrain state in cold deformation, and analyzed the TB8material deformation agingstrengthening mechanism.It concluded that cold deformation could increase the graindislocations, prompt a large number of precipitates produced during the heat treatmentprocess, and precipitates and dislocations played a pinning effect, under the interactionbetween these two,the aging strengthening had been further strengthened, so as toincrease the amount of cold deformation, precipitates increased,the hardness of thematerial was greatly enhanced. This paper used the method to combine numerical analysis and experimenttogether,Shortened the design cycle of process and die and reduced the cost. Anappropriate way of forward extrusion deformation forming parts was determined.weformed a qualified components, made originally less than1300MPa TB8productsoverall strength increased after cold deformation strengthening process,eventuallyreached and exceed the product acceptance criteria.