Crack‐induced intergranular corrosion behavior of aerial aluminum alloy subjected to severe plastic deformation.

The influence of crack‐induced on the intergranular corrosion (IGC) behavior of aerial aluminum alloy subjected to severe plastic deformation (SPD) is investigated in this work. Addressing this problem, a particular SPD technology, namely elliptical cross‐sectioned spiral equal channel extrusion (ECSEE), is employed to prefabricate cracks. The microstructure, induced‐crack observation and IGC behavior of the ECSEE‐ed alloy are observed. ECSEE can significantly refine the grains, while lots of small and deep dimples as well as broken second‐phase particles appear on fracture surface. The formation mechanism of the fracture surface is revealed based on the observation of fracture morphology. A typical stress corrosion cracking characteristic is observed in IGC tested ECSEE‐ed alloy, and the corroded fracture consisted of higher volume fraction of brittle intergranular fractures that are made up of rockcandy‐like brittle and intergranular fracture. The mechanism of intergranular corrosion of dehiscence and cracking is determined considering the factors such as grain refinement, grain boundary precipitations, preexisted crack, and residual stress. The influence of crack‐induced on the intergranular corrosion (IGC) behavior of aerial aluminum alloy subjected to severe plastic deformation (SPD) is investigated. The mechanism of intergranular corrosion of dehiscence and cracking is determined considering the factors such as grain refinement, grain boundary precipitations, preexisted crack, and residual stress. [ABSTRACT FROM AUTHOR]