Microstructure Evolution Of 5A02 Aluminum Alloy During Isothermal Hot Shear Deformation

Shear bending is a new method of forming small bending radius tube, which is suitable for the forming of small bending radius tube of aluminum alloy. Considering the shear bending forming of small bending radius tube in a certain temperature is helpful to improve the mechanical peoperties of the tube, and the microstructure of the formed tube will change during the progress, which is related to the performance of the formed tube. Therefore, it is necessary to explore the law of microstructure evolution.It is very hard to observe the process of the microstructure evolution only through the experiment, in order to have a deep understand about the microstructure evolution of the process of the hot shear bending forming, this paper builded multiphase field model coupling with the dislocation density model based the Ginzburg-Landau equation, which simulating the microstructure evolution of the process of the hot shear bending forming.In order to verify the applicability of the model, this paper combined the simulation and the experiment to explore the law of the microstructure evolution of the aluminum alloy hot shear bending forming, established the relationship of stress-strain and the critical dynamic recrystallization model, in addition to, identified the deformation activation energy and the dynamic recrystallization activation energy, and Qa is 1.8433 ? 105kJ/mol, Qb is 19961J/mol. Other parameters related to the microstructure evolution are identified by searching the papers.Using the designed device of the hot shear bending forming to explore the influence of the different deformation temperature、different deformation rates and different deformation degree on the hot shear bending forming of the 5A02 aluminum alloy, observing the microstructure evolution of the progress by the metallographic microscope, identify the influence of thr above factors on the microstructure evolution.Using the established multiphase field model to explore the different temperature, different deformation rates, different mobility and different nucleation parameters of microstructure evolution process, and analyzed the influence of the different hot shear bending process on the microstructure evolution. The results are in good agreement with the experiment dates and the simulation results reported in the literature, showing the established model has great applicability.