Removing the oxide layer from magnesium alloys to allow successful EBSD data collection

Instruments used

PECS™ II and EDAX^® Velocity™ Super EBSD analysis system with EDAX APEX™ software

Background

To obtain valid electron backscatter diffraction (EBSD) orientation measurements, the true structure of a specimen must be undistorted and continuous to the surface. Routinely, mechanical or electropolishing is applied to prepare a specimen surface for analysis. However, on certain materials like magnesium or zinc alloys that are extremely susceptible to oxidation, an oxide layer may quickly form when the sample comes into contact with water. This may happen during polishing or afterward by exposure to water vapor in the air during transport or storage. Such an oxide layer effectively blocks the observation of EBSD patterns and has to be removed before analysis.