Synchrotron white Laue nanodiffraction study on the allotropic phase transformation between hexagonal and monoclinic Cu6Sn5

The allotropic phase transformation of Cu6Sn5 from a hexagonal (eta) to monoclinic (eta') structure at 186 degrees C is scientifically interesting and technologically important. As the eta' lattice is crystallographically pseudosymmetrical with eta, the identifications of eta and eta' 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 eta-to-eta' transformation and phase distribution by Laue diffraction via synchrotron white X-ray radiation with a 70 nm x 70 nm focused beam is conducted. The allotropic species (eta and eta') can be well distinguished, and two-stage phase transformation kinetics is proposed. (C) 2021 The Author(s). Published by Elsevier B.V.

Automated summary

The allotropic phase transformation of Cu6Sn5 from a hexagonal to monoclinic structure at 186 degrees C is studied using synchrotron white X-ray Laue diffraction method, which successfully distinguishes the η and η' structures and proposes a two-stage phase transformation kinetics.