316H不锈钢母材与焊缝在模拟沿海大气中的高温腐蚀行为

High Temperature Corrosion Behavior of 316H Stainless Steel Base Metal and Weld in Simulated Coastal Atmosphere

采用高温腐蚀试验,研究了316H不锈钢母材与焊缝在520℃模拟沿海大气环境中长达3000 h的高温腐蚀行为。采用扫描电镜、能谱仪和X射线衍射仪对腐蚀产物形貌和成分进行了观察和分析,并探讨了其腐蚀机理。结果表明:焊缝与母材的腐蚀质量增加曲线均符合抛物线规律;高温腐蚀3000 h后,母材和焊缝试样的腐蚀均轻微,氧化层致密且无剥落,主要成分为(Cr,Fe)_(2)O_(3),其腐蚀速率分别为0.44,0.61μm/a,均小于0.001 mm/a,均属于完全耐蚀级别;焊缝试样的腐蚀速率略大于母材,原因是母材中的Cr与Mo含量较高。

The high temperature corrosion behavior of 316H stainless steel base metal and weld in simulated coastal atmospheric environment was studied by high temperature corrosion test at 520℃for 3000 h.The morphology and composition of corrosion products were observed and analyzed by scanning electron microscopy,energy dispersive spectrometer and X-ray diffractometer.The corrosion mechanism was discussed.The results show that the corrosion mass increase curves of the weld and base metal conformed to the parabolic law.After 3000 h of high temperature corrosion,the corrosion of base metal and weld samples was slight,and the oxide layer was dense and without spalling.The main component was(Cr,Fe)_(2)O_(3),and the corrosion rates were 0.44 and 0.61μm/a,respectively,both of which were less than 0.001 mm/a,all of which belonged to the complete corrosion resistance level.The corrosion rate of the weld sample was slightly higher than that of the base metal because of the higher content of Cr and Mo in the base metal.