阴极极化和ZnAl合金涂层对海水中16Mn钢环境敏感断裂的影响

IOCAS-IR > 海洋环流与波动重点实验室

	阴极极化和ZnAl合金涂层对海水中16Mn钢环境敏感断裂的影响
	刘洋
学位类型	博士
	2000
学位授予单位	中国科学院海洋研究所
学位授予地点	中国科学院海洋研究所
学位专业	海洋化学
关键词	阴极极化 Znal合金氢脆应力腐蚀开裂
摘要	本论文重点研究了阴极极化对海水中16Mn钢环境敏感断裂的影响，以及不同成分ZnAl合金涂层对海水中16Mn钢应力腐蚀开裂的影响。研究表明，16Mn钢在海水中对应力腐蚀开裂并不敏感，但是，当对16Mn钢施加阴极极化电位以防止腐蚀时，随着阴极极化电位的负移，16Mn钢在海水中对应力腐蚀开裂的敏感性增加；从样品的断口形貌中可以看出，阴极极化电位为－900mv时，断口有明显的脆性断裂特征；从而可以推断出阴极过保护将促进16Mn钢在海水中发生氢脆。当对16Mn钢进行热浸镀涂层保护之后，研究不同成分ZnAl合金涂层对海水中16Mn钢应力腐蚀开裂的影响表明，ZnAl合金在海水中处于活性溶解状态，合金本身在海水中对应力腐蚀开裂并不敏感，但是具有ZnAl合金涂层的样品在海水中却对应力腐蚀开裂敏感，其原因是在拉伸的过程中出现微小的裂纹，合金涂层则起到牺牲阳作用；在裂纹处形成大阳极，小阴极，产生了过保护现象；随着合金涂层与16Mn钢电偶腐蚀电流的增大，合金涂层样品的延伸率反而变小。这进一步说明16钢在海水中对氢是敏感的，容易发生氢脆现象。
其他摘要	The effect of cathodic polarization on environment sensitive cracking of 16Mn steel in seawater and the effect of different hot-dip ZnAl alloy coating on stress corrosion cracking of 16Mn steel in seawater were studied in this paper. The results show that 16Mn steel is not sensitive to stress corrosion cracking in seawater, but when cathodic polarization is done on 16Mn steel to prevent from uniform attacking, with the decreasing of cathodic potential, the susceptivity to environment sensitive cracking of 16Mn steel is increasing. From the morphology of the fractured surface of 16Mn at different cathodic potential, fractured surface of 16Mn steel at -900mv has obvious brittle characteristics. Over cathodic protection will accelerate hydrogen brittlement of 16Mn steel in seawater. The effect of different hot-dip ZnAl coating on stress corrosion cracking of 16Mn steel in seawater is also studied. ZnAl alloy is in active dissolution state in seawater and not sensitive to stress corrosion cracking. But. 16Mn steel with ZnAl alloy coating is sensitive to stress corrosion cracking in seawater because where there are tiny cracks, ZnAl alloy coating has a function of sacrificing anode. Great anode and little cathode make 16Mn steel at cracks over protection. With the increasing of galvanic current between different ZnAl alloys and 16Mn steel, elongation rate of 16Mn steel with hot-dip alloy coating decreases. 16Mn steel in seawater is sensitive to hydrogen embrittlement.
页数	62
语种	中文
文献类型	学位论文
条目标识符	http://ir.qdio.ac.cn/handle/337002/935
专题	海洋环流与波动重点实验室
推荐引用方式 GB/T 7714	刘洋. 阴极极化和ZnAl合金涂层对海水中16Mn钢环境敏感断裂的影响[D]. 中国科学院海洋研究所. 中国科学院海洋研究所,2000.

条目包含的文件
文件名称/大小	文献类型	版本类型	开放类型	使用许可
LW003407.pdf（3188KB）			限制开放	--	浏览