Investigation of the de-alloying behaviour of θ-phase (Al2Cu) in AA2024-T351 aluminium alloy. (July 2016)

• Record Type: Journal Article
• Authors: Zhang, X.; Hashimoto, T.; Lindsay, J.; Zhou, X.
• Is Part Of: Corrosion science. Volume 108(2016)
• Page Start: 85
• Page End: 93
• Publication Date: 2016-07
• Subjects: A. Aluminium -- A. Intermetallic -- B. SEM -- B. TEM -- C. De-alloying; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2016.03.003
• Languages: English
• ISSNs: 0010-938X

Abstract

Highlights: De-alloying might occur preferentially at S-phase in the multi-phase particles. The de-alloying of θ-phase resulted in porous copper-rich θ-phase remnant. Banding structure developed during the de-alloying of θ-phase that contains stacking faults. The de-alloying of θ-phase could preferentially occur from beneath alloy surface. Abstract: For multi-phase intermetallic particles consisting of both θ-and S-phase, de-alloying occurred preferentially at S-phase and the de-alloying of θ-phase initiated in the regions surrounding S-phase. The selective dissolution of Al from θ-phase resulted in porous copper-rich θ-phase remnant, comprised of randomly oriented copper metallic particles and copper oxides with sizes of 10–50 nm. Banding structure developed during the de-alloying of θ-phase particles that contain stacking faults. The de-alloying of θ-phase could preferentially occur from beneath the alloy surface, associated with the local low pH environment generated by trenching of the alloy matrix in the periphery θ-phase particles.