X-Ray Microbeam Measurements of Individual Dislocation Cell Elastic Strains in Deformed Single Crystal Copper


Lyle E. Levine, B C. Larson, W Yang, M E. Kassner, J Z. Tischier, M A. Delos-Reyes, Richard J. Fields


The distribution of elastic strains (and thus stresses) at the sub-micrometer length scale within deformed metal single crystals has surprisingly broad implications for our understanding of important physical phenomena. These include the evolution of the complex dislocation structures that govern mechanical behavior within individual grains, the transport of dislocations through such structures, changes in mechanical properties that occur during reverse loading (e.g. sheet metal forming), and the analyses of diffraction line profiles for microstructural studies of these phenomena. We present the first direct measurements of the elastic strains within individual dislocation cells in copper single crystals deformed in tension and compression along <100> axes. Broad distributions of elastic strains are found, with profound implications for theories of dislocation structure evolution, dislocation transport, and the extraction of dislocation parameters from X-ray line profiles.
Citation: Nature Materials
Pub Type: Journals
Created August 26, 2016, Updated February 17, 2017