市政给排水管道缝隙腐蚀行为研究
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摘要
对给排水管道用TP140钢进行了模拟市政给排水管道水中应力条件下的缝隙腐蚀试验。结果表明,无论有无外加应力,缝隙的存在都会加剧TP140钢材料的腐蚀,使得有缝隙试样的腐蚀速率远大于无缝隙试样;随着外加应力从0.6σ增加至1.0σ,TP140钢的最大腐蚀深度和平均腐蚀深度都呈现为先减小而后增加的趋势,在外加应力为0.8σ时取得最小值;相对于未施加外加应力条件,随着外加应力的增加,无缝隙和有缝隙条件下试样的腐蚀电位均向负向移动,且腐蚀电流密度均增大。施加外加应力,TP140钢的耐腐蚀性能降低,且有缝隙试样的腐蚀更为严重;外加应力试样的交流阻抗谱图中容抗弧的半径有所减小,腐蚀速率有所加快,这表明外加应力使材料的电化学阻抗降低,加速了TP140钢的腐蚀。
The crevice corrosion test of TP140 steel under the stress condition of simulated municipal water supply &drainage pipeline was investigated. The results show that the existence of gap will increase the corrosion of the TP140 steel whether with or without external stress, leading to that the corrosion rate of sample with gap is far greater than the seamless samples. The maximum corrosion depth and the average corrosion depth of TP140 steel presents a trend of decreasing first and then increasing with the increase the applied stress from 0.6 σ to 1.0 σ, and the minimum value is obtained when the applied stress is 0.8 σ. With the increase of stress, the corrosion potential of specimens with and without gap shifts to negative direction compared to that without applying stress, and the corrosion current density increases. The corrosion resistance of TP140 steel decreases after applying stress, and the corrosion of specimen with gap is more serious.Compared to the sample without applying external stress, the capacitive arc radius in AC impedance spectrum decreases for the sample with applying external stress, and the corrosion is accelerated, which indicates that the external stress would make the electrochemical impedance of materials reduce, thereby accelerating the corrosion of TP140 steel.
The crevice corrosion test of TP140 steel under the stress condition of simulated municipal water supply &drainage pipeline was investigated. The results show that the existence of gap will increase the corrosion of the TP140 steel whether with or without external stress, leading to that the corrosion rate of sample with gap is far greater than the seamless samples. The maximum corrosion depth and the average corrosion depth of TP140 steel presents a trend of decreasing first and then increasing with the increase the applied stress from 0.6 σ to 1.0 σ, and the minimum value is obtained when the applied stress is 0.8 σ. With the increase of stress, the corrosion potential of specimens with and without gap shifts to negative direction compared to that without applying stress, and the corrosion current density increases. The corrosion resistance of TP140 steel decreases after applying stress, and the corrosion of specimen with gap is more serious.Compared to the sample without applying external stress, the capacitive arc radius in AC impedance spectrum decreases for the sample with applying external stress, and the corrosion is accelerated, which indicates that the external stress would make the electrochemical impedance of materials reduce, thereby accelerating the corrosion of TP140 steel.
引文
[1]邬可胜.浅谈给排水管道防腐施工新技术研究应用分析[J].全面腐蚀控制,2016,30(9):87-89.
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[4]刘星,陈聪聪,李谋成.409型不锈钢在冷凝液中的缝隙腐蚀行为[J].腐蚀与防护,2017,38(5):383-386.
[5]刘艳朝,赵国仙,薛艳,等.超级13Cr钢在高温高压下的抗CO2腐蚀性能[J].全面腐蚀控制,2011,25(11):29-34.
[6]Han D,Jiang Y M,Shi C,et al.Effect of temperature,chloride ion and p H on the crevice corrosion behavior of SAF 2205 duplex stainless steel in chloride solutions[J].Journal of Materials Science,2012,47(2):1018-1025.
[7]Machuca L L,Bailey S I,Gubner R,et al.Effect of oxygen and biofilms on crevice corrosion of UNS S31803 and UNS N08825 in natural seawater[J].Corrosion Science,2013,67(1):242-255.
[8]Yang Y Z,Jiang Y M,Li J.In situ investigation of crevice corrosion on UNS S32101 duplex stainless steel in sodium chloride solution[J].Corrosion Science,2013,76(10):163-169.
[9]Nakatsu M.Effects of Sulphate,Nitrate and Bicarbonate Ions on Occurrence and Repassivation of Crevice Corrosion for13Cr Stainless Steel Healds in Diluted Na Cl Solution[J].Zairyo-to-Kankyo,2013,62(11):454-459.
[2]翁窈瑶.市政给排水管道的耐蚀设计与优化[J].热加工工艺,2015,44(6):216-218.
[3]Tachibana M,Ishida K,Wada Y,et al.Effects of gamma-ray irradiation on crevice corrosion repassivation potential of stainless steel in high temperature diluted simulated seawater[J].Journal of Nuclear Science&Technology,2016(7):1-11.
[4]刘星,陈聪聪,李谋成.409型不锈钢在冷凝液中的缝隙腐蚀行为[J].腐蚀与防护,2017,38(5):383-386.
[5]刘艳朝,赵国仙,薛艳,等.超级13Cr钢在高温高压下的抗CO2腐蚀性能[J].全面腐蚀控制,2011,25(11):29-34.
[6]Han D,Jiang Y M,Shi C,et al.Effect of temperature,chloride ion and p H on the crevice corrosion behavior of SAF 2205 duplex stainless steel in chloride solutions[J].Journal of Materials Science,2012,47(2):1018-1025.
[7]Machuca L L,Bailey S I,Gubner R,et al.Effect of oxygen and biofilms on crevice corrosion of UNS S31803 and UNS N08825 in natural seawater[J].Corrosion Science,2013,67(1):242-255.
[8]Yang Y Z,Jiang Y M,Li J.In situ investigation of crevice corrosion on UNS S32101 duplex stainless steel in sodium chloride solution[J].Corrosion Science,2013,76(10):163-169.
[9]Nakatsu M.Effects of Sulphate,Nitrate and Bicarbonate Ions on Occurrence and Repassivation of Crevice Corrosion for13Cr Stainless Steel Healds in Diluted Na Cl Solution[J].Zairyo-to-Kankyo,2013,62(11):454-459.