High-temperature electron backscatter diffraction and scanning electron microscopy imaging techniques: In-situ investigations of dynamic processes

In-situ heating experiments have been conducted at temperatures of approximately 1200 K utilising a new design of scanning electron microscope, the CamScan X500. The X500 has been designed to optimise the potential for electron backscatter diffraction (EBSD) analysis with concomitant in-situ heating experimentation. Features of the new design include an inclined field emission gun (FEG) column, which affords the EBSD geometrical requirement of a high (typically 160degrees) angle between the incoming electron beam and specimen surface, but avoids complications in heating-stage design and operation by maintaining it in a horizontal orientation. Our studies have found that secondary electron and orientation contrast imaging has been possible for a variety of specimen materials up to a temperature of at least 900degreesC, without significant degradation of imaging quality. Electron backscatter diffraction patterns have been acquired at temperatures of at least 900degreesC and are of sufficient quality to allow automated data collection. Automated EBSD maps have been produced at temperatures between 200degreesC and 700degreesC in aluminium, brass, nickel, steel, quartz, and calcite, and even at temperatures >890degreesC in pure titanium. The combination of scanning electron microscope imaging techniques and EBSD analysis with high-temperature in-situ experiments is a powerful tool for the observation of dynamic crystallographic and microstructural processes in metals, semiconductor materials, and ceramics.