Electron diffraction mapping for strain analysis of grain boundary, and its application for mineralogy

Abstract

We obtained electron diffraction mapping from grain boundaries of minerals using conventional TEM, in order to analyze local strain quantitatively. The samples are sillimanite-mullite coexistence from Asama volcano and rainbow-garnet with fine lamellae from Tenkawa, Nara. Diffraction patterns were automatically obtained, while incident electron beam was scanned on the samples. As the results, d-spacing images can be constructed. From the garnet sample, strain distribution near the boundaries between the host and lamellae is successfully visualized.