高氮奥氏体不锈钢点蚀行为的电化学噪声特征  

Characteristics on Electrochemical Noise of Pitting Corrosion for High Nitrogen Austenitic Stainless Steels

作　　者：安朋亮 梁平[1] 任建民[1] 史艳华[1] 刘峰[1] 陈思瑶 AN Pengliang1, LIANG Ping1, REN Jianmin1, SHI Yanhua1, LIU Feng1, CHEN Siya2(1 School of Mechanical Engineering, Liaoning Shihua University, Fushun 113001, China; 2 North Hua Jin ChemicalIndustries Group Corporation, Panjin 124021, Chin)

机构地区：[1]辽宁石油化工大学机械工程学院,抚顺113001 [2]北方华锦化学工业集团有限公司,盘锦124021

出　　处：《中国腐蚀与防护学报》2018年第1期26-32,共7页Journal of Chinese Society For Corrosion and Protection

基　　金：国家自然科学基金(51175240)~~

摘　　要：通过对电化学噪声数据进行时域、频域和Weibull分布等分析,比较了高氮奥氏体不锈钢(HNSS)和316L不锈钢(316L SS)在6%(质量分数)FeCl_3溶液中的点蚀行为。时域分析结果表明,316L SS在溶液中浸泡5 h后,电位噪声和电流噪声均出现了噪声暂态峰,试样表面发生了亚稳态点蚀,而此时HNSS并没有出现明显的噪声暂态峰,电位噪声和电流噪声仅发生小幅高频波动,表面钝化膜虽发生轻微腐蚀,但仍具有一定的再钝化能力。316L SS的噪声电阻波动幅值较大,而HNSS噪声电阻幅值在小范围内波动,表面钝化膜的自钝化和修复能力优于316L SS。功率谱密度图像表明,316L SS的高频段斜率和白噪声水平强度均高于HNSS,且Weibull分布分析表明316L SS的点蚀孕育速率约是HNSS的2倍,316L SS更容易发生点蚀,HNSS的抗点蚀能力更强。The pitting corrosion behavior of high nitrogen stainless steel（HNSS） and 316 L stainless steel（316 L SS） in 6%（mass fraction） Fe Cl3 solution was compared by time domain, frequency domain spectrum and Weibull distribution analysis of electrochemical noise（EN） data. The time domain analysis results show that after immersion in the solution of 6%FeCl3 for 5 h, the noise transient peaks appear on the measured potential noise and current noise of 316 L SS, implying the occurrence of metastable pitting, however, at the same time, the noise transient peak does not appear on the EN plot of HNSS, while the potential noise and current noise only presented a slight high-frequency fluctuations, indicating the surface passivation film suffered from slightly attack, while presented ability of repassivation to certain extent. Moreover, the noise resistance fluctuation amplitude of 316 L SS is larger than that of HNSS, which suggesting the ability in self-passivation and re-healing of the passivation film of HNSS is better than that of 316 L SS. Plots of power spectral density show that the values of slope of high frequency and plateau intensity of white noise of 316 L SS are larger than those of HNSS, and the relevant Weibull distribution analysis reveals that the rate of pitting inoculation for 316 L SS is twice of that for HNSS, which predicating that the 316L SS is much prone to pitting than HNSS.

关 键 词：高氮不锈钢 电化学噪声 功率谱密度 

分 类 号：TG174.3[金属学及工艺—金属表面处理]