Journal of Materials Research and Technology (Jul 2021)
Synchrotron white Laue nanodiffraction study on the allotropic phase transformation between hexagonal and monoclinic Cu6Sn5
Abstract
The allotropic phase transformation of Cu6Sn5 from a hexagonal (η) to monoclinic (η′) structure at 186 °C is scientifically interesting and technologically important. As the η′ lattice is crystallographically pseudosymmetrical with η, the identifications of η and η′ and their transformation are extremely difficult via traditional techniques, such as electron backscatter diffraction, transmission electron microscopy, or, X-ray powder diffraction. Herein, a study of the η-to-η′ transformation and phase distribution by Laue diffraction via synchrotron white X-ray radiation with a 70 nm × 70 nm focused beam is conducted. The allotropic species (η and η’) can be well distinguished, and two-stage phase transformation kinetics is proposed.