Phase transformations and microstructural changes of a furnace cooled eutectoid Zn-Al based alloy were studied during ageing at 100 and 170°C using X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. Three phase transformations occurred in the furnace cooled eutectoid Zn-Al alloy. The metastable η′FCphase decomposed during isothermal ageing. The four-phase transformation, α + ε → T′ + η followed the discontinuous decomposition of the η′FCphase. Typical morphologies of the decomposition of the η′FCand ε phases were observed in scanning electron microscopy. Decomposition of Al-rich α phase was observed during the prolonged ageing by transmission electron microscopy. The different types of decomposition of the different metastable phases dominated at different stages of ageing.
ASJC Scopus subject areas
- Materials Science(all)