Solute Segregation to Grain Boundaries

This kind of analysis is most effectively conducted in a dedicated FEGSTEM instrument, which has an increased beam current while maintaining a small probe size. Such instruments also permit the detection of light elements such as B at boundaries. It has become possible to map the distribution of grain-boundary 

Carpenter et al. (1999) prepared, by sputter depositing on NaCl, a lOOnm Al film alloyed with 4 wt% Cu. This they stabilized for 1 h at 475°C, then aged for 4h at 

The mapping conditions were chosen by the authors to minimize the frame time and to maximize the counting statistics by increasing the probe size and probe current, while reducing the number of pixels in the map. These authors summarized the effect of the low-magnification mapping parameters on the measured analytical resolution for their specimen/microscope combination in Table 5.1. 

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