Crystallographic Distribution of Low Angle Grain Boundary Planes in Magnesium Oxide

We have developed a technique that allows all five macroscopically observable grain boundary degrees of freedom to be characterized for a statistically significant number of interfaces. Using this technique, we have characterized 5 x 10 μm of grain boundary plane area in a 0.15 mm volume of MgO. The observations demonstrate that there is significant texture in the distribution of boundary planes. Here we compare the observed distribution of grain boundary planes at low misorientation angles (~ 5 °) to the calculated geometrically necessary dislocation content of the same interfaces. Based on the inverse correlation between these two quantities, we conclude that relatively low energy configurations are adopted with the highest frequency.