The effect of anodic polarization on the ambient creep of brass

• Published in: Corrosion science 1994-08, Vol.36 (8), p.1437-1445
• Main Authors: Gu, B., Chu, W.-Y., Chu, W., Qiao, L.-J., Hsiao, C.-M.
• Format: Article
• Language: English
• Subjects: Applied sciences; Creep; Exact sciences and technology; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/0010-938X(94)90191-0

The effect of anodic and cathodic polarizations on the ambient creep of brass in 3.5% NaCl and CH 3COOH + CH 3COONa solutions has been investigated. The results showed that the creep rate in both solutions increased linearly with the increase of the anodic current density and was approximately inversely proportional to the square of the radius of the specimen. The dε/dt in 3.5% NaCl solution was much higher than that in the CH 3COOH + CH 3COONa solution at the same anodic current density. The creep rate resulting from dislocation climb induced by vacancy supersaturation during the anodic polarization has been calculated as follows: dϵ dt = K βi r 2 where K = 8 παMϱD s ΔtΔr/ C 0 dFZ ln ( R/ b), and β is a constant related to the degree of de-alloying. The experimental data support the proposed mechanism. Cathodic polarization could also increase the ambient creep of brass by a mechanism related to hydrogen-facilitated local plastic deformation.