Effects Of High Magnetic Field On Microstructure And Texture Evolution In Cold-Rolled Pure Copper By Magnetic Field Annealing

In the present study, the diamagnetic pure copper sheet was selected as the original materials. Magnetic field was applied during the different kinds of heat treatments. Microhardness of the magnetically treated samples was examined by the conventional methods; texture and microtexture were investigated by XRD and EBSD analysis, respectively. Based on the experimental results and comparisons with the samples treated without magnetic field, observed the exact position of nuclei formation and the orientation of nuclei in the initial stage of recrystallization, the effects of high magnetic field on the process of grain growth in samples is equally important, finally illustrate the effects of magnetic field on microstructure and texture evolution in cold-rolled pure copper by magnetic field annealing.The samples were annealed at different temperature(160℃,180℃,200℃) for 5min, with different magnetic field strength(0T,12T). During the magnetic field annealing, the magnetic field was applied along the samples’rolling direction and transverse direction, respectively.The results were similar when magnetic field direction parallel to the samples’ rolling direction or transverse direction. (1)The microhardness of samples with magnetic field was higher; the area percentage of recry stall ized regions in samples with magnetic field was lower; the evolution of grain boundary misorientation distribution in annealed samples with magnetic field was slower. Which showed that applied the magnetic field, the process of recrystallization was hindered, and the effect was more obvious when the magnetic field’s direction parallel to the transverse direction. The reason was that the structure sensitiveness of magnetic free energy in materials, in order to maintain the system at the lowest free energy state, magnetic field would inhibit the recrystallization. (2)In the process of annealing, the evolution of texture in samples with magnetic field was slower;{001}<100> component was the main texture components in the annealed samples with and without magnetic field, and {001}<100> component in the samples with magnetic field was stronger. Although magnetic field hindered the recrystallization process, has promoted the development of {001}<100> oriented recrystallization grains. (3)The exact position of nuclei formation was{123}<634> component, because its higher strain energy. (4) The E3 CSL grain boundary has been restrained by high magnetic field.The samples were annealed at 250℃ for different time (5min,30min,120min), with different magnetic field strength (OT,12T). During the magnetic field annealing, the magnetic field was applied along the samples’ rolling direction and transverse direction, respectively.The results were similar when magnetic field direction parallel to the samples’rolling direction or transverse direction. (1) The microhardness of samples with magnetic field was lower, it was proved that more completely grain growth in samples with magnetic field. (2) high magnetic field has promoted the development of {001}<100> oriented recrystallization grains, the effect was more obvious when the magnetic field’s direction parallel to the rolling direction, The reason was that anisotropy of magnetic susceptibility in materials. (3) The ∑3 CSL grain boundary has been restrained by high magnetic field.