摘要
文章分析了X70钢板的点蚀成因并提出了控制措施,试验表明,X70钢的氧化皮均呈现分层情况,氧化皮内有较多裂纹,结构疏松、不致密,导致层流冷却水中的盐分在X70钢氧化皮中残留,使得X70钢氧化皮内的盐分较高,是导致其在存储过程中发生点蚀的主要原因。磷酸根作为一种缓蚀性阴离子,能够提高材料的自腐蚀电位,并与其他离子相互作用,改善氧化皮的保护性能,但含氧酸根本身就能引起点蚀,所以往层流冷却水中添加PO43-的方法需谨慎。
The paper analyses pitting corrosion form and control of X70 plate.The appearance of the pit under oxide film is shown as a small pit mouth at the interface and a big volume in the matrix.Discussion of the examination results and the survey of literature have led to the conclusion,that the reason of pitting corrosion of X70 micro-alloyed steel plate is the influence of chlorine ions in the cooling water and the concentrating of the aggressive species in rolling process promote the pitting corrosion further.The oxide film had little protective function to the substrate.The laminar structure and micro-cracks among the oxide film may provide the thoroughfare to reach the matrix for the aggressive species,such as chlorine ions.In the results,it is shown that the PO3-4 has inhibition effect on the pitting corrosion in the cooling water,but it needs more research in the application.
出处
《钢铁研究学报》
CAS
CSCD
北大核心
2010年第6期26-30,44,共6页
Journal of Iron and Steel Research
关键词
X70管线钢
点蚀
氧化皮
X70 micro-alloyed steel
pitting corrosion
oxide film
