Texture and grain-boundary misorientation distributions in Y123 ceramics deformed by torsion under pressure

Open School-Conference of NIS Countries Ultrafine Grained and Nanostructured Materials

Imayev, M.F.^1 ; Kabirova, D.B.^1

Institute for Metals Superplasticity Problems, Russian Academy of Sciences, 39 Khalturin st., Ufa

450001, Russia^1

关键词: Biaxial textures;    Deformed samples;    Grain boundary misorientation;    High Tc superconductors;    Low angle grain boundaries;    Misorientation angle;    Non-basal textures;    Strong fibers;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/447/1/012013/pdf
DOI  :  10.1088/1757-899X/447/1/012013

来源: IOP

【 摘 要 】

Texture and grain-boundary misorientation distributions in different parts of the sample of the high-T c superconductor Y123 deformed by torsion under pressure at 1008 °C to a twist angle of 30° were investigated. The average levels of the basal plane texture (the Lotgering factor F) of undeformed and deformed samples were F = 0.25 and 0.965, respectively. In the undeformed sample, the fraction of low-angle grain boundaries (LAGBs) with misorientation angles from 2° to 10° does not exceed 5%. The deformation led to the formation of a strong, but non-uniform texture along the radius of the sample. In the center of the sample, a strong fiber texture is formed with the [001]-axis parallel to the axis of compression / torsion, and the fraction of LAGBs is about 20%. At a distance of 2 mm from the center of the sample there is a ring with a non-basal texture, where the fraction of LAGBs reaches 30%. A biaxial texture is formed at the edge of the sample: the [001] axis is parallel to the axis of compression / torsion, and the [110] axis is oriented along the radius of the sample. The fraction of LAGBs at the edge of the sample is 56%.