Hot Deformation Properties And Bending Of Stiffened Panel Of AZ31 Magnesium Alloy

Due to the special physical properties and abundant magnesium resources,the development and application of magnesium alloy materials have been widely concerned by scholars at home and abroad.Among them,the application of magnesium alloy in aerospace is an important research direction.In this paper,the hot deformation behavior of AZ31 magnesium alloy and the deformation law of progressive compression bending process of ribbed magnesium alloy integral panel were studied by numerical simulation and experimental methods,and the evolution law of microstructure during deformation was analyzed(1)According to the material stress-strain curve and the constitutive equation of hyperbolic sine model(Arrhenius type),the constitutive relation model of hot deformation of AZ31 magnesium alloy is established,which provides a theoretical basis for determining the plastic forming process parameters and optimizing the die structure.(2)According to the theory of work hardening rate,the critical conditions of dynamic recrystallization of AZ31 magnesium alloy under hot deformation were determined.The relationship between the critical conditions and deformation parameters was analyzed.The models of critical stress,peak strain and steady-state strain were established,which provided a theoretical model for numerical simulation of microstructure during composite deformation.(3)Deformation-3D software was used to simulate the progressive bending process of magnesium alloy panel.Cellular automata method was used to analyze the microstructure evolution of magnesium alloy integral panel during the bending process.The temperature field and stress field in the deformation zone were analyzed.The deformation process parameters were determined and the die structure was optimized.(4)The progressive bending method was used to process the integral panel of magnesium alloy with ribs.The surface quality of the machined parts was good.The change law of grain size in the machined parts was analyzed.The increase of deformation temperature and reduction can promote the occurrence of dynamic recrystallization of magnesium alloy and improve the grain refinement.(5)The curvature radius of the stiffened magnesium alloy integral panel was analyzed.The relationship model between the curvature radius and the process parameters was determined.The relative errors of the simulation results,experimental results and model calculation results were analyzed.The relative error between the simulation results and the experimental results is less than 10%.The relative error between the calculated results and the experimental results is less than 6%.