Study On Evolution Of Defomation-Solid-Ageing Microstructure And Properties Of 2A14 Aluminum Alloy

2A14 aluminum alloy is widely used in aerospace and transportation.It belongs to Al-Cu-Mg-Si series high-strength heat-resistant aluminum alloy and contains a small amount of Mn.Because of its heat resistance,it can be used to make complex shapes.Free forgings and die forgings.2A14 aluminum alloys are commonly used in thermoforming.Different thermoforming conditions have a great influence on the properties of the formed materials.The evolution of deformation-solid solution-aging microstructure properties of 2A14 aluminum alloy under different deformation conditions can not only provide the basis for finite element simulation,but also provide a theoretical basis for actual production.In the forming process of aluminum alloys,the forming conditions affect the mechanical properties and the evolution of the materials.The flow stress constitutive equation of 2A14 aluminum alloy is established in this paper,and the thermal compression experiments at different deformation temperatures and rates are performed using Geeleble 3500.The average relative error is mostly below 5%,indicating that this equation predicts the flow stress of 2A14 aluminum alloy.The effect is good.Dynamic recrystallization needs to reach its critical condition.Critical conditions are determined by true stress-strain curves and equations.The volume fraction prediction model and dynamic recrystallization dimension prediction model for dynamic recrystallization are established.A certain degree of growth occurs as the deformation rate and temperature increase.Deformation curves of metal materials are usually related to dislocations.In combination with the obtained models and dislocation theory,we modified the rheological strain model at high strain rates.This equation predicts the flow stress ratio of Arrhenius equation.The predicted flow stress is more accurate.The different thermal deformation conditions affect the deformed microstructure of the material.The strain energy during hot deformation promotes the static recrystallization during cooling.In this paper,the artificial heat treatment process of artificially aged 2A14 aluminum alloy was analyzed.The microstructure and properties after heat treatment were analyzed.The higher the dislocation density of deformation accumulation,the higher the alloy's storage capacity and the higher its strength.Different deformation conditions also have an effect on the dynamic recrystallization of 2A14.The dynamic recrystallization degree of the sample at high temperature and low rate is large,but at the same time,the crystal grains are also coarse.The combination of thermal deformation and cold deformation,through the strengthening of cold deformation,is conducive to promoting the dissolution of the second phase and improving the shape of the second phase,and ultimately improving the comprehensive mechanical properties of the material.In order to study the influence of deformation condition on the second-phase ?? conversion rate during aging,the isothermal conversion rate curve was obtained based on the DSC temperature-temperature conversion curve by using the JMAK equation,and the isothermal conversion curve constants under different deformation conditions were obtained.The relationship between isothermal conversion curve constants and deformation conditions.Different dislocation conditions will result in different dislocation densities,but the dislocation density of the solid solution will decrease,and most of them are very close.The precipitation of the second phase is determined by both dislocations and grains.Large dislocation density and small grain size after solid solution promote the precipitation of the second phase.The relationship between isothermal transformation curve constants and deformation conditions is established,and the deformation aging conditions can predict the second-phase aging precipitation curve.