Use of EBSD to identify phases in interdendrite region of a cast Zn-Al-based alloy (ZA27)

Electron backscattered Kikuchi diffraction methodology was used to identify phases in the interdendrite region of an alloy ZA27. Two Zn-rich hexagonal close-packed structure phases η and ε phases were distinguished using predetermined lattice parameters of the phases. In relation to studies of scanning electron microscopy and X-ray diffraction, electron backscattered diffraction results revealed that the Al-rich precipitates of the α phase were from decomposition of the η′T, and the four-phase transformation: α + ε → T′ + η, had occurred in the ε phase after ageing at 150°C for 8 h.