Multi-Scale Simulation Of 2219 Aluminum Alloy Ring Rolling Forming

2219 aluminium alloy ring parts are mainly used in the aerospace and marine industries.They are usually in service under high pressure,high temperature and kinematic loads,and therefore have high requirements for their production quality.Radial-axial ring rolling is an important method for the production of high quality large rings,which are formed as a whole,but is a complex non-linear deformation process.It is therefore important to investigate the macro-forming and microstructural changes in 2219 aluminium alloy during radial-axial ring rolling.In this paper,the following studies are done around the macroscopic integral forming process and microstructural changes of 2219 aluminium alloy ring parts:1.A material rheological stress model containing two stages of work hardeningdynamic reversion and dynamic recrystallization was established.According to the ring rolling results,the changes in grain shape and second phase particles were analysed.A hot compression test was set up,based on which a rheological stress model containing two stages of work-hardening-dynamic recovery and dynamic recrystallisation was constructed,and this model can be used for the numerical analysis of the hot working process of 2219 aluminium alloy.2.Based on the flow stress model,a macroscopic finite element model for the diameter-axial ring rolling of 2219 aluminium alloy is established.Based on this model,the stress field,strain field,temperature field,roundness of the ring,cross-sectional quality and other deformation states of the ring rolling process are analysed;the stress concentration is mainly located in the deformation zone consisting of the rolls,the higher strain is located at the edges of the ring,while the temperature distribution is higher in the internal temperature and lower in the external temperature.The rolling force varies as an increase followed by a decrease and then tends to dynamic stability.The roundness and thickness error of the ring increases and then decreases,and the height error gradually increases with deformation。3.A dynamic recrystallisation cellular automaton model is developed which takes into account the dislocation changes,recrystallisation nucleation and nucleation growth.Based on the dynamic recrystallisation cellular automata model,the process of nucleation,growth,reduction in average grain size and microstructural changes at grain boundaries was investigated.During the rolling process,both the original and recrystallised grains are compressively deformed and the grains are gradually elongated in the tangential direction.The model is validated by comparing the grain size and morphology of the experimental results with the simulation results.The effect of processing conditions on dynamic recrystallisation was also investigated and results were obtained for lower strain rates and higher recrystallisation percentages at higher temperatures under the same conditions.