Nanocrystalline materials are defined by their fine grain size, but detailsof the grain boundary character distribution should also be important. Grainboundary character distributions are reported for ball milled, sputterdeposited, and electrodeposited Ni and Ni-based alloys, all with average grainsizes of ~20 nm, to study the influence of processing route. The two depositedmaterials had nearly identical grain boundary character distributions, bothmarked by a {\Sigma}3 length percentage of 23-25%. In contrast, the ball milledmaterial had only 3% {\Sigma}3-type grain boundaries and a large fraction oflow angle boundaries (16%), with the remainder being predominantly random highangle (73%). These grain boundary character measurements are connected to thephysical events that control their respective processing routes. Consequencesfor material properties are also discussed with a focus on nanocrystallinecorrosion. As a whole, the results presented here show that grain boundarycharacter distribution, which has often been overlooked in nanocrystallinemetals, can vary significantly and influence material properties in profoundways.
展开▼
