Abstract The corrosion tests of G20Mn5QT cast steel and butt weld with Q345D steel in wt 3.5% NaCl solution are conducted. The corrosion morphology of the specimens is observed by SEM. It is mainly corrosion pitting for G20Mn5QT cast steel due to the casting defect and the erosion of chloride ions. The corrosion morphology of weld zone and HAZ tends to be uniform corrosion accompanied with pitting corrosion. Welding defect and erosion of chloride ions cause pitting corrosion for weld zone and HAZ. The largest circular radius of the divided circular pits is defined as the maximum radius of the irregular pit.

中文翻译：

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G20Mn5QT铸钢与Q345D钢对接焊缝腐蚀行为的试验研究

摘要 进行了G20Mn5QT铸钢及Q345D钢对接焊缝在wt 3.5% NaCl溶液中的腐蚀试验。通过扫描电镜观察试样的腐蚀形貌。G20Mn5QT铸钢主要是由于铸造缺陷和氯离子侵蚀而产生的点蚀。焊缝区和热影响区的腐蚀形态趋于均匀腐蚀并伴有点蚀。焊接缺陷和氯离子侵蚀造成焊缝区和热影响区的点蚀。划分的圆形凹坑的最大圆形半径定义为不规则凹坑的最大半径。