Microradiographic Characterization of Pitting Corrosion Damage and Fatigue Life

Effects of actual marine atmospheric precorrosion and prefatigue on the fatigue property of 7085-T7452 aluminum alloy were investigated by using the methods of marine atmospheric outdoor exposure tests and constant amplitude axial fatigue tests. Marine atmospheric corrosion morphologies, fatigue life, and fatigue fractography were analyzed. After three months of outdoor exposure, both pitting corrosion and intergranular corrosion (IGC) occurred, while the latter was the dominant marine atmospheric corrosion mode. Marine atmospheric precorrosion could result in a dramatical decrease in the fatigue life of the as-received 7085-T7452 aluminum alloy, while selective prefatigue can improve the total fatigue life of the precorroded specimen. The mechanism of the actual marine atmospheric corrosion and its effects on the fatigue life of the 7085-T7452 aluminum alloy were also discussed.

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Investigation of pitting corrosion damage of a hydraulic press trunk piston

Engineering Failure Analysis ◽

10.1016/s1350-6307(02)00041-9 ◽

2003 ◽

Vol 10 (2) ◽

pp. 251-254 ◽

Cited By ~ 1

Author(s):

Changli Wang ◽

Yuexian Cui ◽

Li Cui

Keyword(s):

Pitting Corrosion ◽

Corrosion Damage ◽

Hydraulic Press

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Characterization of pitting corrosion in aluminum films by light scattering

Applied Physics Letters ◽

10.1063/1.122472 ◽

1998 ◽

Vol 73 (17) ◽

pp. 2432-2434 ◽

Cited By ~ 14

Author(s):

Y.-P. Zhao ◽

C.-F. Cheng ◽

G.-C. Wang ◽

T.-M. Lu

Keyword(s):

Light Scattering ◽

Pitting Corrosion ◽

Aluminum Films

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Simulation Investigation on Environment-Induced Pitting Corrosion on the Metal Surface

Science of Advanced Materials ◽

10.1166/sam.2021.3940 ◽

2021 ◽

Vol 13 (5) ◽

pp. 820-828

Author(s):

Wei Zhang ◽

Shengli Lv ◽

Leijiang Yao ◽

Xiaoyan Tong

Keyword(s):

Mathematical Model ◽

Pitting Corrosion ◽

Three Dimensional ◽

Corrosion Damage ◽

Sudden Onset ◽

Ion Concentration ◽

Two Dimensional Image ◽

Aging Aircraft ◽

Efficient Calculation ◽

The Mathematical Model

The prediction of corrosion damage is one of effective research methods in the safety inspection of aging aircraft structures. A mathematical model for quantifying corrosion damage is used in this paper to predict the onset of corrosion on structural surfaces exposed to aggressive environments. Based on the finite difference technique, the evolution process of local pitting corrosion on the surface of aluminum alloy in the medium is simulated, which can consider the sudden onset and the randomness of pitting corrosion. The effect of local ion concentration and oxide film damage on subsequent pitting nucleation was analyzed. Based on the efficient calculation program, the effectiveness of the mathematical model is verified by the comparison between the corrosion damage morphology and the experimental data in the literature. The results show a more widespread distribution of subsequent pits because of stronger aggressive ions are released during the life cycle of active pits and the higher diffusion coefficient of the aggressive ions. The three dimensional morphology is generated by image processing method based on the gray value of the two dimensional image of pits.

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