Thermal stability of gradient microstructure in a low-alloyed Cu-Cr-Zr alloy

•Stable ultrafine grain microstructure in Cu-0.1%Cr-0.1%Zr after ECAP and aging.•Number of ECAP passes effects on recrystallization temperature.•Recrystallization temperature is limited by recrystallization mechanisms.•The chromium content controls the kinetic of recrystallization temperature degradation. The thermal stability of gradient microstructures in a Cu – 0.096%Cr – 0.07%Zr (wt.%) alloy subjected to equal channel angular pressing (ECAP) at 400 °C was studied. The microstructure after intense plastic straining and aging at 300–500 °C was almost the same. Aging at 600 °C led to the development of a partially recrystallized microstructure. After aging at 700 °C, the fully recrystallized microstructure evolved. An increase in ECAP passes from 1 to 12 decreased the recrystallization temperature from 664 °C to 617 °C. The effect of deformation microstructures and particle precipitation on the recrystallization development is discussed.