Exploring structural similarities between crystal phases using EBSD pattern comparison

Abstract

We discuss the application of EBSD for the analysis of structural features of magnetite and hematite relevant in the topotactic growth of both phases. The orientation relationships of both phases are investigated using characteristically related sets of Kikuchi patterns, which were collected from topotactically intergrown hematite variants and their parent magnetite crystal grain. We address the hexagonal description of trigonal and cubic phases with respect to crystallographic relationships. The combination of locally resolved EBSD measurements and microstructural investigations thus offers a promising opportunity to evaluate orientation relationships and intergrowth between magnetite and hematite.

Point-group sensitive orientation mapping of non-centrosymmetric crystals

“…8 Typical applications include EBSD-based lattice strain analysis, 9 EBSD image segmentation, 10,11 and the analysis of orientation relationships in phase transformations. 12 Moreover, EBSD-based chirality determination was recently demonstrated. 13 With respect to crystal structures that show a broken inversion symmetry, A III B V compound semiconductors in their cubic and hexagonal modifications are of great relevance for optoelectronic and photonic applications.…”

The Potential of EBSD and EDS for Ceramics Investigations—Case Studies on Sherds of Pre‐Columbian Pottery

“…The mineral phases of the non‐plastic inclusions were identified by using locally acquired single EBSD patterns, or averaged patterns from small EBSD maps measured on distinct temper particles with a small sampling size. Phase assignment was based on the qualitative elemental composition and a pattern‐matching of experimental and simulated patterns using dynamical theory (Nolze and Winkelmann ). For example, as inferred from the chemical information, in our assessment of EBSD pattern matching by cross‐correlation of a feldspar inclusion in sample BDX 14743, we suspect the particle to be a member of the alkali feldspar series (Na,K)AlSi 3 O 8 ) with the end‐members high albite and high sodium sanidine, and low albite and microcline, respectively.…”

“…In work designed as case studies on examples of Wari , Moche and Cajamarca ceramics, we demonstrate the crystallographic, chemical and microstructural input gained by SEM–EDS and EBSD through a single sample preparation technique, by the making of polished block sections. On the basis of the correct interpretation of high‐resolution Kikuchi patterns by means of dynamical EBSD pattern simulation (Nolze and Winkelmann ), we provide evidence of the mineral phases and intergrowths of the temper grains.…”

Electron backscatter diffraction beyond the mainstream

“… between magnetite and hematite are only 0.4 so that a reliable discrimination of these two phases by η is unlikely, especially when surface topography exists. Fortunately, the pattern correlation is not that strong as for magnetite and wuestite so that a separation by EBSD only is not problematic . Also FeOOH – goethite (α), akaganeite (β), lepdocrocite (γ) – shows a clear difference in so that BSE in combination with EDX can be used for an identification of FeOOH if no or only locally BKD patterns are available.…”