Experimental Study And FEM Simulation Of The Electromagnetic Forming Process Of Titanium Alloy (TC4) Sheet Metal

Titanium alloy（TC4）has been widely used in aerospace and automobile industriesbecause of characters like low density, high strength, and high temperature serviceperformance, etc. But as there are only three slip systems in TC4alloy, the formingprocess is difficult to conduct at room temperature. The hot forming technology is mostlyused in titanium alloy sheet metal forming process, such as super plastic forming, creepforming, laser forming, etc. But owing to the high rejection rate, serious pollution andeasy oxidation, the forming performance of titanium alloy sheet metal still needs to beimproved. Because TC4is a kind of strain rate sensitive material, and the electromagneticforming is a forming technology which can provide high strain rate, and the characteristicsof the forming conditions can be easily controlled, so on the basis of previous research,this paper proposed an forming technology of TC4sheet metal at room temperature byusing electromagnetic forming with a driver plate. The free bulging process of TC4sheetmetal could be conducted by the electromagnetic forming technology with a driver plate.This process is safe, highly controllable, non-pollution and the forming efficiency isrelatively high.The electromagnetic forming principle of TC4sheet metal was studied in the paper,and forming process was conducted through the experiment, and some key parameters ofthe forming process, such as discharge voltage, current, frequency, deformation speed ofsheet metal forming process were obtained by advanced test techniques. The deformationstrain and thickness changes of the TC4sheet metal were also studied. These workprovided the foundations for the later study of finite element simulation of this formingprocess. The microstructure of formed TC4sheet metal was studied by EBSD technique.By comparing the microstructure of original sheet metal, quasi-static formed sheet metaland the electromagnetic formed sheet metal, the effect of electromagnetic forming on themicrostructure evolution of TC4sheet metal was studied. The study found that theelectromagnetic formed titanium alloy TC4sheet caused the change of phase proportionand grain size, but compared with the quasi-static forming, electromagnetic forming did not significantly change the texture of TC4sheet metal.Based on the experimental study, this paper proposed a finite element simulationmethod of the electromagnetic forming process with a driver of TC4sheet metal. Firstlythe finite element model of electromagnetic field study was built in ANSYS. Thedistribution of electromagnetic field and electromagnetic force were obtained. Secondlythe structure model was built in Abaqus, and then the electromagnetic force was loaded tothis model. By calculating the structure model, some important parameters were obtainedsuch as deformation speed, impact force, strain and stress, etc. Comparing with theexperimental study, this numerical simulation method was validated, and some processingproperties were analyzed.