A spray-cast Al-7034 alloy was processed by equal-channel angular pressing (ECAP) to a total of 8 passes at 473 K and the pressed samples were examined using transmission electron microscopy, differential scanning calorimetry and electron back-scatter diffraction. It is shown that the grain size of the alloy is reduced to ~0.3 um by ECAP and the high pressures associated with ECAP lead to a fragmentation of the rod-like eta-phase. The high temperature of ECAP also produces a precipitation of eta-phase. There is an increase in the fraction of high-angle boundaries during the initial passes of ECAP but the fraction of low-angle boundaries remains high even after 8 passes.
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