Misorientations across etched boundaries in deformed rocksalt: a study using electron backscatter diffraction

Automated electron backscatter diffraction (EBSD) in the scanning electron microscope has been used to collect crystallographic orientation and misori entation data from etched surfaces of deformed synthetic rocksalt. By compa ring the misorientation across individual boundaries to the intensity of et ching, we have assessed the effectiveness of the etching procedure. High an gle (>10 degrees) grain boundaries are typically etched significantly more than low angle subgrain boundaries, and thus they can be easily identified using reflected light microscopy. However, there exists considerable variat ion in the intensity of etching of subgrain boundaries, independent of thei r misorientation. The intensity of intragranular boundary etching is contro lled by the crystallographic orientation of the etched surface: surfaces cl ose to {100} faces are only lightly etched, while surfaces close to {111} f aces are heavily etched. Therefore, whilst reflected light microscopy of et ched surfaces of deformed rocksalt remains extremely useful for general mic rostructural characterisation, fully quantitative techniques such as EBSD a re ideal for more detailed microstructural analyses. (C) 1999 Elsevier Scie nce Ltd. All rights reserved.