Grain boundary segregation is a critical issue in materials science because it determines the properties of individual grain boundaries and thus governs the macroscopic properties of materials. Recent progress in electron microscopy has greatly improved our understanding of grain boundary segregation phenomena down to atomistic dimensions, but solute segregation is still extremely challenging t...

The grain boundary character distribution (GBCD) is a direct measurement that can be determined from a single planar section. Since the GBCD is inversely related to the grain boundary energy distribution, it offers a useful metric for validating grain boundary energy calculations. Comparisons between the measured GBCD and calculated energies for 388 grain boundaries in Al show that, for boundar...

The extrinsic grain boundary dislocations (EGBD's) in copper have been studied by transmission electron microscopy. It was shown that some EGBD's remain on grain boundaries after recrystallization and annealing at 0.6 T,, but not on those annealed at 0.8 T,. For several grain boundaries the crystallography of the defects was examined in detail and the dynamic theory of diffraction was used for ...

Ultra-high purity alumina was sintered in hydrogen at temperatures ranging from 13251 to 20201C. Normal grain growth was maintained in all samples and grain boundary mobilities were measured. The data represent the most complete measure of intrinsic grain boundary mobility for alumina grain growth currently available. There are two orders of magnitude of discrepancy between the calculated and m...

A stereological method is described for estimating the distribution of grain-boundary types in polycrystalline materials on the basis of observations from a single planar section. The grain-boundary distribution is expressed in terms of five macroscopically observable parameters that include: three parameters that describe the lattice misorientation across the boundary and two parameters that d...

Grain boundaries and their networks have a profound influence on the functional and structural properties of every class of polycrystalline materials and play a critical role in structural evolution and phase transformations. Recent experimental advances enable a full crystallographic characterization, including the boundary misorientation and inclination parameters, of grain boundaries. Despit...

Single grain boundaries in CuGaSe2 have been grown epitaxially. Hall measurements indicate a barrier of 30-40 meV to majority carrier transport. Nevertheless, local surface potential measurements show the absence of space charge around the grain boundary; i.e., it is neutral. Theoretical calculations [Persson and Zunger, Phys. Rev. Lett. 91, 266401 (2003)] have predicted a neutral barrier for t...