Lee Yun-Ho, Hong Min-Sung, Ko Sang-Jin, Kim Jung-Gu
School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Korea.
Materials (Basel). 2021 May 21;14(11):2722. doi: 10.3390/ma14112722.
Carbonaceous residues on copper pipes during the manufacturing process are known to be one of the main causes of pitting corrosion on copper pipes. This study examined the corrosion-inhibiting effect of benzotriazole (BTA) on C12200 copper pipes with carbonaceous film in synthetic tap water. In the absence of BTA, localized corrosion mechanisms due to galvanic corrosion, crevice corrosion, and oxygen-concentration cell were proposed in the boundary part of the carbonaceous film on the copper through X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) with energy dispersive spectrometer (EDS) analyses. Electrochemical tests showed that BTA inhibits corrosion by forming Cu-BTA complexes on all over the copper surface where carbonaceous film is present. BTA mitigates galvanic corrosion and crevice corrosion at the boundary of the carbonaceous film and suppresses the formation of oxygen-concentration cells through the formation of a Cu-BTA complex.
制造过程中铜管上的碳质残渣是已知的铜管点蚀主要原因之一。本研究考察了苯并三唑（BTA）对合成自来水中带有碳质膜的C12200铜管的缓蚀作用。在没有BTA的情况下，通过X射线光电子能谱（XPS）、配备能谱仪（EDS）的扫描电子显微镜（SEM）分析，在铜上碳质膜的边界部分提出了由于电偶腐蚀、缝隙腐蚀和氧浓差电池引起的局部腐蚀机制。电化学测试表明，BTA通过在存在碳质膜的整个铜表面形成Cu-BTA络合物来抑制腐蚀。BTA减轻了碳质膜边界处的电偶腐蚀和缝隙腐蚀，并通过形成Cu-BTA络合物抑制了氧浓差电池的形成。
