Three-dimensional morphology and composition of omega precipitates in a binary titanium-molybdenum alloy

Using atom probe tomography, the three-dimensional morphology and composition of nanoscale omega precipitates in a simple binary titanium-molybdenum alloy have been uniquely determined. The results include the average composition of the omega precipitates and the partitioning of Mo across the omega/beta interfaces. These investigations also revealed compositional inhomogeneity within the nanoscale precipitates, with the presence of a Mo-rich core, presumably arising from the relatively slow rate of Mo rejection during isothermal growth of these omega precipitates. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.