Characterization of Microstructure Inhomogeneity in UFG Copper after Static Annealing and Creep Exposure

0385922 - ÚFM 2013 RIV CZ eng A - Abstract
Král, Petr - Dvořák, Jiří - Kvapilová, Marie - Sklenička, Václav
Characterization of Microstructure Inhomogeneity in UFG Copper after Static Annealing and Creep Exposure.
Book of abstracts S4G, 7th International Conference on stereology, Spatial Statistics and Stachastic Geometry. Praha: Matfyzpress, 2012 - (Lachnerová; Beneš, V.). s. 39-40. ISBN 978-80-7378-207-8.
[International Conference on Stereology, Spatial Statistics and Stachastic Geometry - S4G /7./. 25.06.2012-28.06.2012, Praha]
Institutional support: RVO:68081723
Keywords : Inhomogeneity of microstructure * creep behaviour * ultrafine-grained materials
Subject RIV: JJ - Other Materials

Experiments were conducted to evaluate an effect of static annealing and creep on homogeneity of microstructure in pure Cu processed by equal-channel angular pressing (ECAP) at room temperature. The experimental material used in this investigation was a coarse-grained copper having the mean grain size ~ 1.2 mm in its received state. The billets were processed by ECAP using a die that had an internal angle of 90° between the two parts of the channel and an outer arc of curvature of ~ 20°, where these two parts intersect. It can be shown from first principles that these angles lead to an imposed strain of ~ 1 in each passage of the sample through the die [1]. The ECAP pressing was performed by route Bc up to 8 passes. The microstructure after 2 and 8 ECAP passes was annealed at from 373 to 573 K for 5 min, 10 and 100 h. Constant load creep tests in tension were conducted at 373, 473 and 573 K under different applied stresses. Microstructure of samples was characterized by scanning electron microscope (SEM) equipped with the electron backscatter diffraction unit (EBSD). The data obtained by EBSD were analyzed at two values of boundary misorientations (subgrains with Δ ≥ 2° and grains with Δ ≥ 15°).
Permanent Link: http://hdl.handle.net/11104/0215242