Lv Shanglin, Li Kefei, Chen Jie, Li Xiaobin
Department of Civil Engineering, Tsinghua University, Beijing 100084, China.
National Construction Steel Quality Supervision and Test Centre, Central Research Institute of Building and Construction, China Metallurgical Group Cooperation, Co., Ltd., Beijing 100088, China.
Materials (Basel). 2020 Oct 27;13(21):4790. doi: 10.3390/ma13214790.
The stress corrosion cracking is the central issue for high-strength wires under high tensile stress used in civil engineering. This paper explores the resistance of stress corrosion cracking of three typical steel wires of high-strength carbon through a laboratory test, combining the actions of tensile stress and corrosive solution. Besides, the impact of tensile stress and immersion time are also investigated. During the tests, the wires were subject to electrochemical measurements of potentiodynamic polarization and electrochemical impedance spectroscopy, and the microstructure analysis was performed on the fractured cross sections. The obtained results show the following: the high-strength wire, conforming to GB/T 5224, has higher resistance to the combined actions of tensile stress and corrosive solution; tensile stress of 70% fracture strength and longer loading-immersion time make the film of corrosion products on steel surface unstable and weaken the corrosion resistance; the surface film consisted of the iron oxide film and the corrosion products film whose components are mainly iron thiocyanate and iron sulphide.
应力腐蚀开裂是土木工程中使用的承受高拉应力的高强度钢丝的核心问题。本文通过实验室试验，结合拉应力和腐蚀溶液的作用，探究了三种典型高强度碳素钢丝的应力腐蚀开裂抗性。此外，还研究了拉应力和浸泡时间的影响。在试验过程中，对钢丝进行了动电位极化和电化学阻抗谱的电化学测量，并对断裂横截面进行了微观结构分析。所得结果表明：符合GB/T 5224的高强度钢丝对拉应力和腐蚀溶液的联合作用具有较高的抗性；70%断裂强度的拉应力和较长的加载-浸泡时间会使钢表面的腐蚀产物膜不稳定并削弱耐腐蚀性；表面膜由氧化铁膜和主要成分是硫氰酸铁和硫化铁的腐蚀产物膜组成。
