Manipulating Precipitation Through Thermomechanical Treatment to Control Corrosion Behavior of an Al–Cu–Mg Alloy

• Published in: Acta metallurgica sinica : English letters Vol. 35; no. 9; pp. 1547 - 1558
• Main Authors: Zhu, Xiu-Rong, Wang, Jun, Shi, Wei-Ning, Liu, Xue-Bing, Zhang, Xin-Fang, Zhou, Hai-Fei
• Format: Journal Article
• Language: English
• Published: Beijing The Chinese Society for Metals 01.09.2022; Springer Nature B.V
• Subjects: Aging; Aging (natural); Alloys; Aluminum alloys; Aluminum base alloys; Characterization and Evaluation of Materials; Chemistry and Materials Science; Cold; Cold rolling; Copper; Corrosion and Coatings; Corrosion potential; Corrosion prevention; Corrosion resistance; Corrosion tests; Deformation; Grain boundaries; Intergranular corrosion; Interiors; Low temperature resistance; Magnesium; Materials Science; Metallic Materials; Microscopy; Morphology; Nanotechnology; Organometallic Chemistry; Phase distribution; Pitting (corrosion); Pitting potential; Radiation; Spectroscopy/Spectrometry; Thermomechanical treatment; Tribology; Precipitation; Pitting corrosion; Intergranular corrosion; Thermomechanical treatment
• ISSN: 1006-7191; 2194-1289
• DOI: 10.1007/s40195-022-01385-8

Controlling the precipitation through thermomechanical treatment is an important method to improve the corrosion resistance of Al–Cu–Mg alloys. In this study, the corrosion behaviors of Al–Cu–Mg alloys in the solution-treated state and retrogression-treated state under cold rolling deformation and then natural aging were investigated. In the solution-treated series alloys, the cold-rolled deformation improved the resistance to intergranular corrosion by suppressing the precipitation of the S-phase on the grain boundaries. The increased pitting potential and corrosion potential were related to the increased concentration of solute atoms within the grain interiors and the eliminated S-phase on grain boundaries. In the retrogression-treated series alloys, the 30% cold rolling deformation stimulated the growth of the S-phase and transformed the S-phase distribution from discontinuous to continuous on the grain boundaries, thereby changing the pitting corrosion to the network corrosion morphology. The precipitation of the S-phase with large dimension within the grain interiors contributed to the decreased pitting potential and corrosion potential.