Influence of equal-channel angular pressing on the corrosion fatigue behaviour of an Al-Mg-Si aluminium alloy for automotive conductors

[Display omitted] •ECAP induced an increase in fatigue lifetime in air due to grain refinement.•Pre-corrosion and corrosion fatigue led to a decrease in fatigue lifetime.•A synergy between cyclic mechanical loading and corrosion processes was shown.•IMC breakdown led to more corrosion defects and a decrease in fatigue lifetime.•Higher sensibility to pre-corrosion and corrosion fatigue was found after ECAP. The influence of equal channel angular pressing (ECAP) on the corrosion fatigue behaviour of an Al-Mg-Si alloy was studied. Preliminary fatigue tests in air showed an increase in fatigue lifetime for ECAP samples, as compared to as-received samples, related to the ECAP-induced grain refinement. After pre-corrosion, the fatigue lifetime was lower for ECAP samples than for as-received samples, because the fragmentation of coarse intermetallics during ECAP led to an increase in the density of corrosion defects. Corrosion fatigue tests demonstrated a synergy between cyclic mechanical loading and corrosion processes for all samples; a deleterious effect of ECAP was also noted.