EBSD Analysis of Deformation and Determination of Dislocation Density

Wednesday, September 15, 2021: 2:20 PM
242 (America's Center)
Dr. Donald Susan , Sandia National Laboratories, Albuquerque, NM
Dr. Phillip Noell , Sandia National Laboratories, Albuquerque, NM
Ms. Bonnie McKenzie , Sandia National Laboratories, Albuquerque, NM
Ms. Sara Dickens , Sandia National Laboratories, Albuquerque, NM
Electron backscatter diffraction (EBSD) and electron channeling contrast (ECCI) imaging are powerful techniques to observe the amount of deformation and/or recrystallization in cold worked and annealed specimens. Simple inspection of EBSD maps and ECCI images can give a qualitative understanding of the extent of recovery, recrystallization, and grain growth. In addition, based on measurements of relative misorientation between pixels, an estimate of the geometrically necessary dislocation (GND) density can be obtained. This is useful to assess the relationship between GND density and, for example, hardness, ductility, and tensile strength. We show examples from cold-sprayed and annealed coatings, additively manufactured and annealed stainless steel, and surface-machined Fe-Co soft magnetic alloys. The results are correlated with microhardness measurements and tensile testing to determine the degree of recovery, recrystallization, and grain growth as a function of time and temperature for these materials.

Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.