Defect Structure Evolution in HCP-Zirconium Alloys: The Role of Anisotropy

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The evolution of the dislocation structure and the ensemble of boundaries during plastic deformation of Zr-Nb alloys studied using electron microscope. The role of the anisotropy of slip in the formation and restructuring of the boundaries, recurrence of dislocation transformation was established. Special emphasis is placed on specific features of geometrically necessary defects evolution. It was found that the geometrically necessary boundaries formation involves an athermal coalescence as a mechanism of relaxation of large accumulated internal stresses, which prevents fracture in an anisotropic polycrystalline material.

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62-66

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October 2014

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© 2014 Trans Tech Publications Ltd. All Rights Reserved

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