The Effects Of Initial Microstructure On The Microstructure And Properties After Deformation Of TA2 And TC4titanium Alloy

Titanium and its alloys are extensively used due to their high heat resistance, corrosion resistance and other properties. However the limitation of the research has restricted the further application of titanium. This paper mainly studies about pure titanium TA2 and TC4 titanium alloy. To obtain the different initial microstructure by the early different pretreatments, then the thermal simulation experiments in different deformation process were executed on the initial microstructure to study the relationship between the deformation properties and initial microstructure of two kinds of titanium. Finally the cupping forming experiment was conducted on both materials to study the deformation properties. The main contents of this article are as follows:(1) The TA2 pure titanium were annealed at three different temperatures which were in the vicinity of its recrystallization temperature and the phase transition temperature to obtain different grain sizes, different organizations for the thermal deformation experiments.(2) The TC4 titanium alloy were cooled at four kinds of cooling methods followed by the solution treatment to obtain the different initial microstructure,then the thermal deformation experiments were conducted on the material that were cooled at different methods after the solution treatment at 1000?.(3)The thermal simulation experiments were executed on the TA2 pure titanium after annealing. To study the evolution of the different initial microstructure and the deformation properties of the materials after the deformation, we had changed the deformation temperature and the deformation rate in the thermal deformation experiments. When the deformation temperature is 650? and the deformation rate is 10S-1, the peaks of true stress-true strain curve and the hardness values of the material are significantly improved.(4) The thermal simulation experiments were executed on the TC4 titanium after solid solution at 1000?. To study the evolution of the different initial microstructure and the deformation properties of TC4 titanium after the deformation, we used three temperatures750?, 850?,950? in the thermal compression experiments. The peaks of the stress and thehardness values of the samples are relatively larger when the deformation temperature is low.(5) The cupping forming experiment was conducted on the TA2 pure titanium. The TA2 blocks were annealed at different temperatures after cold rolling, then the Erichsen test was executed. The results show that the erichsen value is the biggest and the deformation performance of TA2 is the best after annealing at 550 ?.(6) The cupping forming experiment was executed on the TC4 titanium. Solution and aging treatment at different temperatures and times were executed on the TC4 titanium after cold rolling. The results show that the erichsen value is the biggest and the deformation performance of TC4 is the best after aging treatment at 550? for one hour.The research on deformation behavior of different initial microstructure from TA2 and TC4 titanium alloy can provide a theoretical basis for the control of microstructure and properties of these two materials and it is meaningful for the actual production.