316L不锈钢的非敏化态晶间腐蚀与电位的关系及其敏感性的检测方法

• 作 者: 于福洲 王月平 程华
• 机 构: 北京化工学院应用化学系\\r\\r\\r\\r\\r\\r\\r\\r\\n,北京化工学院应用化学系\\r\\r\\r\\r\\r\\r\
• 出 处: 北京化工学院学报(自然科学版)
• 发表日期: 1987年03期
• 关键词: 晶间腐蚀 过钝化电位 恒电位 腐蚀速度 尿素生产 极化曲线 电位值 暴露面积 动电位扫描 全面腐蚀

用恒电位浸蚀方法在尿素高压釜中和在常温硫酸中研究了尿素级316L不锈钢的非敏化态晶间腐蚀与电位的关系,以及这种晶间腐蚀的发展过程与检测方法。结果表明:非敏化态晶间腐蚀只在过钝化电位区发生;随恒电位浸蚀时间推移(随浸蚀电量增加),晶间腐蚀深度与宽度都加大,腐蚀截面呈V字形;在等电量的恒电位浸蚀条件下,浸蚀电位愈正,则晶间腐蚀速度在总腐蚀速度中所占比例愈小;使用添加NaCl的硫酸或高氯酸溶液在过钝化区进行恒电位浸蚀是检测不锈钢非敏化态晶间腐蚀敏感性的快速而有效的新方法。

The relationship between the non-sensitized intergranular corrosion and potential of urea-grade 316L stainless steel was investigated by potentiostatic etching in urea autoclave and normal temperature sulfuric acid, and the development process and detection method of intergranular corrosion. The results show that intergranular corrosion in non-sensitized state occurs only in the over-passivation potential region. With the increase of etching potential, the depth and width of intergranular corrosion increase, and the corrosion cross-section is V-shaped. Under the conditions of constant potential etchant of equal electricity, the more positive the etching potential, the smaller the intergranular corrosion rate is in the total corrosion rate. The more constant etching rate Potential etching is a fast and effective new method to detect the sensitivity of non-sensitized stainless steel to intergranular corrosion.