Investigation of orientation relationships by EBSD and EDS on the example of the Watson iron meteorite

Abstract

The suitability of the electron back-scatter diffraction technique (supported by EDS) in order to study the complex microstructures of iron meteorites is demonstrated on the example of the Watson meteorite. The orientation relationships between the main phases kamacite, taenite and schreibersite/rhabdite as well as effects of the real structure have been investigated. In kamacite bands highly deformed blocks appear which show a contineous change of orientation. Plessitic regions are surrounded by deformed taenite lamellae. Also these lamellae show the typical M-profile of the Ni concentration in cross section. In the center a martensitic microstructure has been proven. The white plessite is characterized by a high number of individual kamacite grains which however are separated mainly by low-angle boundaries. So an orientation clustering occurs. The determination of orientation relationships was only possible for a single plessite region comparing the intensity distribution in pole figures with simulations. Schreibersite is brittle and shows a high number of microcracks. However, the strong deformation of kamacite does not allow us to decide whether an orientation relationship between the phosphides and the surrounding kamacite exists or not.

Effect of growth temperature on the structural, morphological and magnetic properties of Fe films on GaN(0001)

“…EBSD is the fastest and most reliable method for revealing the crystalline structure and orientation of a single-or multi-phase crystalline solid [18,19]. In addition, EBSD offers high spatial resolution and thus direct visualization of even nano-crystalline grain/domain structures.…”

The mechanisms of the fcc–bcc martensitic transformation revealed by pole figures

“…1 obtained on a 9% Cr steel. Similar features appear in many fcc-bcc martensitic materials such as CuZn brasses [3], bainitic steels [4] and FeNi meteorites [5][6][7]. They are not artefacts that could be attributed to the EBSD method, as Bunge et al also observed them by synchrotron X-ray diffraction [8].…”

“…Kurdjumow-Sachs [9] The determination of the OR can be realized either by filtering the PFs [5,6] or by more complex calculations [4]. Most of the time, the singular features around the averaged OR are simulated by a superposition of NW and KS ORs [13,14] or by a higher number of discrete ORs including NW, KS, GT and other intermediate ORs [7].…”

Investigations of the meteoritic mineral (Fe,Ni)3P

“…If the deformation of the surrounding meteoritic metal is too strong the determination of the OR is problematic or impossible (cf., for the Watson meteorite in [32]). …”