Research on Corrosion Fatigue Performance and Multiple Fatigue Sources Fracture Process of Corroded Steel Wires

Abstract

Corrosion fatigue (CF) failure is one of the typical failure modes of high-strength steel wires for bridge cables because the cables are subjected to long-term fatigue loads and exposed to heavily polluted environment simultaneously. In this paper, a numerical simulation method was proposed to study CF performance of corroded high-strength steel wires. Firstly, the cellular automata (CA) method was used to generate a numerical model of corroded steel wires with corrosion pit, which can accurately describe the electrochemical process of metal corrosion. In the established CA model, three kinds of cells were involved, namely, metal cell, passive film cell, and corrosive medium cell. By setting 10 cellular transformation rules, morphology of the random corrosion pit on the steel wire surface was simulated. And then, a damage evolution model related to coupling of corrosivemedium and fatigue loads (CCF) was developed to describe the CF damage evolution process of steel wires. Subsequently, the damage evolution process was analyzed by ABAQUS with a user-defined material subroutine (UMAT). Finally, the life of corroded steel wires was predicted, and the CF performance of corroded steel wires with multiple corrosion pits was evaluated. The results show that the proposed method can reasonably describe the CF damage evolution process and illuminate the failure mechanism of steel wires subjected to the CCF. Damage of the steel wire with a single corrosion pit evolves gradually, and the damage evolution rate increases. For the steel wires with multiple corrosion pits, the corrosion pits affect mutually in the fracture process. When the angle and distance between corrosion pits reach a certain degree, the mutual effects can be ignored. With the same pit depth, the angle and distance among corrosion pits determine the CF life of steel wires mainly, and the number of corrosion pits affects slightly.

A Simplified Approach for the Corrosion Fatigue Assessment of Steel Structures in Aggressive Environments

“…When corrosive phenomena occur in combination with cyclic loadings, corrosion-induced damage does not simply add up to fatigue damage, but rather, the two processes influence each other. Multiple factors underlie this mutual interaction, namely [ 11 ]: On one hand, corrosion induces a localized reduction of the resisting cross-section, resulting in stress amplifications which accelerate fatigue cracking. Moreover, the fatigue strength of iron oxide products is considerably lower in comparison to that of pristine steel; On the other hand, fatigue cracking creates preferable spots for corrosion development as the cracks can penetrate through protective layers, if present.…”

Effect of stress ratios on corrosion fatigue life of high‐strength steel wires

“…Environmental corrosion can significantly decrease mechanical and fatigue properties of high-strength steel wires, and it had a crucial detrimental role of the remaining fatigue life. 2,3 The main reasons were that the decrease of cross-sectional area and the formation of corrosion pits on the surface of metallic steel wires in a corrosive environment. The existence of corrosion pits decreased the fatigue life significantly, and there was a negative relationship between elongation and ultimate strength and corrosion degree.…”

“…Environmental corrosion can significantly decrease mechanical and fatigue properties of high‐strength steel wires, and it had a crucial detrimental role of the remaining fatigue life 2,3 . The main reasons were that the decrease of cross‐sectional area and the formation of corrosion pits on the surface of metallic steel wires in a corrosive environment.…”

Simulation of pit interactions of multi-pit corrosion under an anticorrosive coating with a three-dimensional cellular automata model

“…The relationship between the value of parameters in CA model and realistic parameters is studied in reference [22]. By selecting appropriate parameters or adjusting parameters through experiments, CA model is recently starting to be used in the study of corrosion and mechanical problems of structural parts [43][44][45].…”