S31655奥氏体不锈钢在湿法磷酸中的腐蚀行为  

Corrosion Behavior of Austenitic Stainless Steel S31655 in a Simulated Wet Process Phosphoric Acid Solution

作　　者：张建斌[1,2] 田欢 欧阳明辉 郝汀 ZHANG Jianbin;TIAN Huan;OUYANG Minghui;HAO Ting(State Key Laboratory of Advanced Processing and Reuse of Nonferrous Metals,Lanzhou University of Technology,Lanzhou 730050,China;Wenzhou Pump and Valve Research Institute of Lanzhou University of Technology,Wenzhou 325000,China;Zhejiang Xuanda Group Corrosion Resistant Special Metal Materials Research Institute,Wenzhou 325000,China;School of Mechanical Engineering,Suzhou University of Science and Technology,Suzhou 215009,China)

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,兰州730050 [2]兰州理工大学温州泵阀研究院,温州325000 [3]浙江宣达集团耐腐蚀特种金属材料研究院,温州325000 [4]苏州科技大学机械工程学院,苏州215009

出　　处：《材料研究学报》2024年第12期902-910,共9页Chinese Journal of Materials Research

基　　金：国家自然科学基金(12075274)。

摘　　要：研究了S31655奥氏体不锈钢在模拟工业湿法磷酸中不同温度下的腐蚀行为。结果表明:随着温度的升高S31655的耐蚀性能降低且存在一个临界温度(60℃),在80℃耐蚀性能显著下降,钝化膜的缺陷浓度ND提高、厚度Wsc减小、稳定性降低且其半导体性在电位高于0.7 V时由n型半导体转为p型半导体。Cr_(2)O_(3)、Fe(III)等通过稳定钝化膜提高耐蚀性,NH_(4)^(+)和NH3配体可对酸性溶液起缓释作用从而抑制腐蚀过程。临界温度的存在与钝化膜中N元素和NH_(4)^(+)在80℃时溶解度的提高相关。温度的升高同时促进了可溶性Fe(H_(2)PO_(4))_(2)和多孔膜的生成,S31655不锈钢中Ni和N的显著富集使Cr_(2)O_(3)沉淀率降低,但是促进了Cr_(2)O_(3)的充分结晶和结构稳定,从而使其耐蚀性提高。The corrosion behavior of austenitic stainless steel S31655 in a simulated industrial wet process phosphoric acid solution at 25℃,40℃,60℃ and 80℃ was investigated by means of electrochemical test and XPS technique.The results show that:with the increasing temperature,the corrosion resistance of S31655 decreases and the is a critical point at 60℃,while the corrosion resistance decreased significantly at 80℃,meanwhile,the defects concentration ND of the formed passivation film increased,its thickness Wsc decreased,and thestability deteriorated,meanwhile,the semi-conductivity of the passivation film transforms from n-type semiconductor to p-type semiconductor by potential above 0.7 V.Results of XPS spectra show that Cr_(2)O_(3)and Fe(III)etc.could improve the corrosion resistance by stabilizing the passivation film,and ligands NH_(4)^(+)and NH3 could inhibit the corrosion process by acting as retardant to acidic solutions.The presence of a critical temperature is associated with an increase in the solubility of N and NH_(4)^(+)in the passivation film at 80℃.The increase in temperature simultaneously promotes the generation of soluble Fe(H_(2)PO_(4))_(2)and porous films,and the significant enrichment of Ni and N in S31655 leads to a decrease in the precipitation rate of Cr_(2)O_(3),but also promotes the full crystallization and structural stability of Cr_(2)O_(3),thereby improving its corrosion resistance.

关 键 词：材料腐蚀与防护 湿法磷酸腐蚀 电化学 钝化膜 含氮奥氏体不锈钢 

分 类 号：TG142.71[一般工业技术—材料科学与工程]