基于元胞自动机的耐候钢腐蚀演化及力化耦合机制研究

Study on Corrosion Evolution and Chemo-Mechanical Coupling of Weathering Steel Based on Cellular Automata

摘要: 腐蚀对南海等严苛海洋大气环境中耐候钢结构的耐久性构成重大威胁，同时受机械应力作用下，局部腐蚀对基础结构的完整性造成了重大挑战。传统方法难以描述点蚀演化及力学作用的影响，该文基于元胞自动机方法，建立腐蚀演化模型，引入有限元模型，构建了力化耦合数值模型。通过Gutman机制将应力应变数据引入腐蚀反应概率，实现应力对腐蚀行为的调控。结果表明：在应力作用下，蚀坑形貌由规则对称逐渐向不规则、深窄发展，最大腐蚀深度随应力增大显著增加。当应力接近材料屈服强度时，最大腐蚀深度提高约55.6%。

Abstract: Corrosion poses a major threat to the durability of weathering steel structures in harsh marine atmospheric environments such as the South China Sea. At the same time, under the action of mechanical stress, localized corrosion poses a major challenge to the integrity of the foundation structure. The traditional method is difficult to describe the evolution of pitting corrosion and the influence of mechanical action. In this paper, based on the cellular automata method, the corrosion evolution model is established, and the finite element model is introduced to construct the mechanical coupling numerical model. Through the Gutman mechanism, the stress-strain data are introduced into the corrosion reaction probability to realize the regulation of stress on the corrosion behavior. The results show that under the action of stress, the morphology of the corrosion pit gradually develops from regular symmetry to irregular and deep narrow, and the maximum corrosion depth increases significantly with the increase of stress. When the stress is close to the yield strength of the material, the maximum corrosion depth is increased by about 55.6%.