Wu Kai, Ge Hong-Hua, Wang Feng, Sha Jun-Yi, Wang Le-Tian, Wan Chuan, Zhao Yu-Zeng, Meng Xin-Jing
Shanghai University of Electric Power, Shanghai Engineering Research Center of Energy-Saving in Heat Exchange Systems, Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power, Shanghai 200090, China.
J Nanosci Nanotechnol. 2018 Dec 1;18(12):8321-8326. doi: 10.1166/jnn.2018.16420.
The surface states of brass in simulated cooling water (SCW) containing or free of sodium dodecyl benzene sulfonate (SDBS) and TiO2 nanofluid were analyzed by means of scanning electron microscope (SEM), energy spectrum analysis (EDS) and X-ray diffraction (XRD). The concentrations of Cu and Zn ions in the solution after brass immersion were analyzed using a plasma emission spectrometer. The relationship between the surface states and corrosion resistance of brass was investigated by electrochemical impedance spectroscopy (EIS). The results showed that the brass surface was mainly covered with zinc compound Zn5(OH)6(CO3)2 as corrosion product in SCW. In SCW containing SDBS, a large amount of SDBS was adsorbed on the brass surface. In TiO2 nanofluid, the brass surface was relatively bare and mainly contained cuprous oxide. There was no obvious adhesion of SDBS aggregates and no accumulation of zinc compound on brass surface in TiO2 nanofluid. TiO2 nanoparticles inhibit the adsorption of SDBS on brass surface. Solution analysis results showed that the concentrations of Cu and Zn ions in TiO2 nanofluid was obviously higher than that in SCW and SCW containing SDBS, indicating that most of corrosion products of brass dissolved into the nanofluid. The EIS results illustrated the brass electrode had a larger reaction resistance in SCW containing SDBS, indicating the good protective performance of the adsorbed SDBS film on brass surface. The reaction resistance of the brass electrode was the smallest in TiO2 nanofluid, which illustrated that TiO2 nanoparticles in solution promoted the corrosion of brass.
通过扫描电子显微镜（SEM）、能谱分析（EDS）和X射线衍射（XRD）对黄铜在含有或不含十二烷基苯磺酸钠（SDBS）和TiO₂纳米流体的模拟冷却水（SCW）中的表面状态进行了分析。使用等离子体发射光谱仪分析黄铜浸泡后溶液中铜离子和锌离子的浓度。通过电化学阻抗谱（EIS）研究了黄铜表面状态与耐蚀性之间的关系。结果表明，在模拟冷却水中，黄铜表面主要覆盖有作为腐蚀产物的锌化合物Zn₅(OH)₆(CO₃)₂。在含有SDBS的模拟冷却水中，大量的SDBS吸附在黄铜表面。在TiO₂纳米流体中，黄铜表面相对裸露，主要含有氧化亚铜。在TiO₂纳米流体中，黄铜表面没有明显的SDBS聚集体附着，也没有锌化合物的堆积。TiO₂纳米颗粒抑制了SDBS在黄铜表面的吸附。溶液分析结果表明，TiO₂纳米流体中铜离子和锌离子的浓度明显高于模拟冷却水和含有SDBS的模拟冷却水，这表明黄铜的大部分腐蚀产物溶解到了纳米流体中。EIS结果表明，黄铜电极在含有SDBS的模拟冷却水中具有较大的反应电阻，这表明吸附在黄铜表面的SDBS膜具有良好的保护性能。黄铜电极在TiO₂纳米流体中的反应电阻最小，这说明溶液中的TiO₂纳米颗粒促进了黄铜的腐蚀。
