船体钢在海洋环境中的力学-化学效应机理及腐蚀模型研究

Corrosion allowance is an effective way to guarantee the safety of hull structures in the whole life cycle; corrosion model of structural materials is the essential factor to determine the correct corrosion allowance, and the stress or strain response of hull structures is an important factor affecting corrosion behavior of structural materials. The present study is to focus on the system of the materials of hull structures, stress and marine environment and investigate the mechanism of mechano-chemical effect from the perspective of the physical principle of materials, and then propose a corrosion model of hull structures based on the mechanism of mechano-chemical effect, thus laying a foundation for the refinement of corrosion allowance of hull structures. The present study decouples the coupling effects of mechanical and chemical factors on hull steels by employing mechano-chemical experiments and the relevant basic theories combined with X-ray diffraction and other techniques suitable for detecting the microstructure of materials, and then proposes a theoretical model for corrosion damage of hull structures under the effect of mechanical factor. By mechano-chemical experiments, the corrosion characteristics and laws of hull steels under the combined effects of mechanical factor and marine environment are studied, and then the developed theoretical model above is verified. Considering the effect of corrosion time, the new corrosion model which can allow for the mechanism of mechano-chemical effect is proposed on the basis of representative corrosion models. Based on the above work, further research is developed on the application of corrosion model in the lifetime prediction of hull structures, and finally this method is verified by long-term field corrosion test.

腐蚀裕量是保障船体结构全生命周期安全性的有效途径，结构材料的腐蚀模型则是确定正确腐蚀裕量的根本要素，而船体结构应力（或变形）响应又是影响结构材料腐蚀行为的重要因素。本项目拟着眼于“船体结构材料-应力-海洋环境”体系，从材料物理原理入手，开展力学-化学效应机理研究，并建立基于力学-化学效应机理的船体结构腐蚀模型，进而为确立精细化的船体结构腐蚀裕量奠定基础。通过X射线衍射等材料微观结构检测技术，结合力学-化学实验及相关基础理论，将力学因素与化学因素对船体钢的耦合腐蚀效应解耦，建立基于力学因素影响的船体结构腐蚀损伤理论模型；通过力学-化学实验测量，研究船体钢在海洋环境和力学因素作用下的腐蚀行为特征及规律，验证腐蚀损伤理论模型；继而通过考虑腐蚀时间的影响，结合经典腐蚀模型，建立基于力学-化学效应机理的新型腐蚀模型。在此基础上，开展新型腐蚀模型在船体结构寿命预测中的应用研究，并通过实海腐蚀实验验证。

腐蚀裕量是保障船体结构全生命周期安全性的有效途径，结构材料的腐蚀模型则是确定正确腐蚀裕量的根本要素，而腐蚀防护措施以及船体结构应力（或变形）响应又是影响结构材料腐蚀行为的重要因素。基于此，本项目以船体钢和防腐涂层为研究对象，围绕其在腐蚀环境、应力场以及阴极保护等因素联合作用下的腐蚀损伤规律和机理，进行了大量的实验研究和理论分析，并开展了基于力学-化学效应机理的新型腐蚀模型研究。本项目创新性地建立了适用于研究力学-化学效应的多通道实验研究系统，为应力场和阴极保护等因素对结构材料腐蚀行为的影响规律以及对涂层防腐功能退化行为的影响规律研究提供了新手段；揭示了应力场对结构材料腐蚀行为的影响机制，建立了相应的影响规律；揭示了应力、阴极保护等因素作用下涂层防腐功能的退化行为；建立了基于力学-化学效应机理的船体结构腐蚀模型，并开展了新型腐蚀模型在船体板壳结构寿命预测中的应用研究。本项目的研究成果为船舶与海洋工程结构的安全设计、腐蚀裕量的选取以及防腐涂层和阴极保护系统的优化设计提供了理论依据。. 基于本项目研究工作取得的进展，现已发表标注资助的学术期刊论文5篇，其中SCI检索4篇，EI检索5篇；参加国际学术合作交流1次；申请并获授权中国发明专利3项；培养毕业硕士研究生2名。