Zn-rich Zn-Al-Cu alloys were produced by milling of elemental powders
mixtures, Zn-22 wt.% Al-3 wt.% Cu and Zn-20 wt.% Al-10 wt.% Cu, for ti
mes of up to 1080 ks. The X-ray diffraction analysis showed the format
ion of alpha (aluminum-rich), eta (zinc-rich) and epsilon (CuZn4) phas
es at the early stage of milling. The presence of epsilon phase was mo
n evident with the increase of copper content in mixture. In the case
of the two alloy compositions. the following phase transformation alph
a + epsilon --> eta + tau' was observed to occur during milling. A mix
ture of eta, alpha and tau' phases was found in powder mixtures milled
for 1080 ks, which is in agreement with phases predicted for these co
mpositions in the equilibrium Al-Cu-Zn phase diagram. Finally, all the
se phases were present on a nanometer scale in both mechanically alloy
ed powders.