The Influence Of Magnetic Field On Diffusion Behavior In Al-Cu Diffusion Couple And Solution And Aging In 2A12 Al Alloy

The magnetic field and the non-magnetic field under different heat treatment were used to study the influence of the magnetic field on the growth regularity of diffusion couple and the effect of magnetic field on solution aging.Al-Cu diffusion couple and 2A12 aluminum alloy were used as the experimental materials.The influence of the magnetic field on the diffusion phase of the Al-Cu alloy was studied.The effects of the magnetic field on the solution aging of the 2A12 aluminum alloy were investigated by applying the pulsed magnetic field in the solution aging process of the 2A12 aluminum alloy.The layer of Al-Cu diffusion-coupling interface shows that there are different phases in the Al-Cu diffusion-couple at different temperatures.The annealing temperature of 400? and 450?,there are three kinds of metal compounds in the diffusion intermediate diffusion layer,respectively CuAl2,CuAl and Cu3Al2.When the diffusion couple is kept at 500?,there are four kinds of metal compounds,CuAl2,CuAl,Cu12Al9 and Cu3Al2,appear in the intermediate diffusion layer.The application of pulsed magnetic field and strong magnetic field did not change the type of phase in the diffusion layer,but changed the thickness of the diffusion layer.The growth of the phase layer under conventional conditions,pulsed magnetic field and strong magnetic field all follow the parabolic law.As the intensity of the pulse magnetic induction increases,the thickness of the intermediate layer of the diffusion couple becomes more and more thick.When the direction of the pulsed magnetic field parallel to the direction of the diffusion,the magnetic field plays a strong role in promoting the diffusion.When the magnetic field gradient is 0,the thickness of the diffusion layer is increased under the steady strong magnetic field.In the gradient magnetic field,both the positive gradient magnetic field and the negative gradient magnetic field can suppress the diffusion of the diffusion couple,and the larger the gradient is,the more obvious the inhibition is.The effect of pulsed magnetic field on the solid solution aging of aluminum alloy was analyzed by applying the pulse magnetic field to the solution aging process of 2A12 aluminum alloy.The results show that when the solute is dissolved at 495?,the solute atoms dissolve into the solvent lattice and cause the distortion of the solvent lattice.The longer the solution time is,the lower the conductivity is.Under the same solution condition,the application of pulsed magnetic field promoted the solid solution of aluminum alloy,and the electrical conductivity of alloy decreased.When the pulse magnetic field is applied in the aging stage of aluminum alloy,the hardness and electrical conductivity of the specimen are higher than those without applying the pulsed magnetic field,which indicates that the pulse magnetic field accelerates the aging process.The application of pulsed magnetic field increases the diffusion rate of the atom,accelerates the dissolution of the eutectic phase and the precipitation of the second phase in the aluminum alloy,and promotes the solution and aging process of the aluminum alloy.