Hou Yanhui, Wang Jingru, Liu Linli, Li Guangqiang, Zhai Dongyu
Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan, Hubei, 430081, China; The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan, Hubei, 430081, China.
Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan, Hubei, 430081, China; The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan, Hubei, 430081, China.
Micron. 2020 Nov;138:102898. doi: 10.1016/j.micron.2020.102898. Epub 2020 Jun 3.
In order to reveal the mechanism of galvanic pitting corrosion initiation induced by typical complex inclusions in Al-Ti-Mg deoxidized high strength pipeline steel, first-principles calculations, combining with immersion tests, scanning electron microscopy was used to study the correlation between electronic work function and galvanic corrosion of Al-Ti-Mg killed steel. The results show that MnS inclusions act as anodes in the electrochemical environment, preferentially corroding and dissolving; MgAlO and AlO inclusions act as cathodes, leading to the corrosion of Fe matrix; different end planes of MgTiO and MgTiO act as both anodes and cathodes, but they have little effect on pitting corrosion. Microcrevices on the MgTiO and MgTiO inclusions boundary are the main cause of matrix dissolution.
为揭示Al-Ti-Mg脱氧高强度管线钢中典型复杂夹杂物诱发电偶点蚀萌生的机制，采用第一性原理计算，并结合浸泡试验、扫描电子显微镜研究了Al-Ti-Mg镇静钢电子功函数与电偶腐蚀之间的相关性。结果表明，MnS夹杂物在电化学环境中作为阳极，优先腐蚀溶解；MgAlO和AlO夹杂物作为阴极，导致铁基体腐蚀；MgTiO和MgTiO的不同端面兼具阳极和阴极作用，但对点蚀影响较小。MgTiO和MgTiO夹杂物边界处的微缝隙是基体溶解的主要原因。
