Microstructural evolution of Al-Mg-Er-Zr alloy by equal channel angular extrusion at room temperature

•The Al3(Er, Zr) particle exists in the initial material.•Saturated dislocations form dense dislocation walls.•Due to CDRX mechanism, the grains are refined to 2.8 μm at room temperature.•The (101) oriented coarse grains are relatively stable once they are formed. To obtain excellent mechanical properties, Al-Mg alloy was processed through a combination of equal channel angular pressing (ECAP) and micro-alloying techniques. In this study, the microstructural evolution of Al-Mg-Er-Zr alloy during ECAP at room temperature were systematically investigated. TEM results confirm that the Al3(Er, Zr) particle exists in the initial material and saturated dislocations form dense dislocation walls. The grains were refined with an average grain size of 2.8 μm after 4 passes of ECAP. Continuous dynamic recrystallization was identified and this mechanism led to the formation of fine grain structure. The (101)-oriented coarse grains were relatively stable once they had been formed.