Research On The Method Of Calculating The Energy Storage Of Pure Aluminum Deformation Structure In Homogeneous And Heterogeneous Structures Based On EBSD Dat

The deformation stored energy in plastically deformed metal microstructures is critical for subsequent recrystallization.The purpose of this study is to develop a method to calculate the deformation stored energy of pure aluminum based on electron backscatter diffraction(EBSD)data,which lays a foundation for the further study of recrystallization.Based on international cooperative research,this paper studies the scientific problem of deformation energy storage calculation of homogeneous structure and heterogeneous structure AA1050 prepared by different deformation methods.AA 1050 pure aluminum samples with homogeneous structure and heterogeneous structure were prepared by rolling,uniform compression and uneven compression,respectively.The deformation microstructure of pure aluminum samples was characterized by EBSD,and the deformation stored energy of different pure aluminum samples was calculated based on the dislocation boundary spacing and misorientation distribution.The dislocation boundary spacing and the misorientation distribution of different samples were obtained by manual statistical method and statistical method using EBSD post-processing software(Channel 5),and the advantages and disadvantages of the above two methods were compared.And then a method for calculating deformation stored energy of pure aluminum based on EBSD data was established.Finally,the relationship between deformation stored energy,texture and microstructure of pure aluminum samples and the microstructure after annealing was studied.The research in this paper is divided into three stages: the calculation method of deformation stored energy described in this paper is established by using the rolling sample with strain of 1.9;The rolling samples with strain of 0.7～3.9 were studied and compared with the relevant data of transmission electron microscope(TEM)to verify the accuracy of the above calculation method.The accuracy of the above calculation method is verified in rolled,uniformly compressed and unevenly compressed samples with strain values of 1.9,and the relationship between deformation stored energy,texture and microstructure and the microstructure of annealed samples is analyzed.The results show that there are significant differences in dislocation boundary spacings and misorientation distributions between manual statistical method and EBSD post-processing software statistical method,especially for the interface with misorientation less than 2°.Through the application of the new method,more accurate dislocation boundary spacings and misorientation distributions can be obtained,and then more accurate deformation stored energy can be calculated.The method proposed in this paper has the characteristics of easy preparation of samples,sufficient statistical data and high accuracy of calculation results,which effectively overcomes the defects of obvious errors in the measurement results of dislocation boundary spacings and misorientation distributions when the traditional EBSD post-processing software processes deformed metal materials.This method is expected to be popularized and applied in other metal materials,which can provide more possibilities for the basic research of recovery and recrystallization of metal materials.