Effect of prior deformation and heat treatment on the corrosion-induced hydrogen trapping in aluminium alloy 2024

Abstract

The nature of the corrosion-induced hydrogen trapping in Al-alloy 2024-T351 was studied by thermal desorption spectroscopy. The microstructure was altered by solution treatment and plastic deformation, prior to corrosion. The results showed that the high temperature, 500. °C, trap state (T4 state) is associated with the S-phase. In the absence of S-phase, hydrogen is trapped at vacancies, which liberate hydrogen at higher temperatures. Plastic deformation prior to corrosion revealed that the trap state at 400. °C (T3 state) is associated with dislocations. High plastic strains (above 0.06) lead to a reduction of hydrogen trapped in both dislocations and the S-phase. © 2013 Elsevier Ltd.