曝晒位置对纯铜热带海洋大气环境腐蚀性能的影响研究

目的研究不同离岸曝晒位置对纯铜热带海洋大气环境腐蚀性能的影响。方法通过对T2铜在三亚热带海滨离岸不同距离进行24个月的大气曝晒试验,结合大气Cl~-在相应位置的沉积量及湿度变化情况,并采用扫描电子显微镜、X射线能谱仪和XRD等对其腐蚀产物形貌、成分和物相进行分析。结果 T2铜热带海洋大气腐蚀以均匀腐蚀为主,其平均腐蚀速率随离岸距离的增加、曝晒时间的延长而下降。腐蚀产物为双层结构,外层为具有疏松结构的绿色Cu_2(OH)_3Cl,内层为致密的Cu_2O。随着离岸距离的增加、暴露时间的延长,试样表面电解液介质中Cl~-浓度越大,T2铜腐蚀产物中Cu_2(OH)_3Cl含量增加,但腐蚀产物生成主要以Cu_2O相为主。结论腐蚀速率与盐雾沉积量与离岸距离变化关系存在差异,盐雾沉积量先升后降,在离岸80 m处有最大值,由于大气相对湿度的影响,导致T2铜腐蚀速率在离岸0 m处有最大值,在离岸80 m处有极大值。

Exposure Position Influences on the Corrosion Resistance of the T2 Copper in Tropic Marine Atmosphere

Objective To study influences on the corrosiveness of pure copper in the tropical marine atmosphere circumstances of different exposure positions. Methods The T2 copper in Sanya tropical beach of different offshore distances was tested for 24 months of marine atmospheric exposure. Combined with the changing conditions of deposition and humidity of Chloride Ion accordingly in the air, morphology, ingredient and phase of the corrosion products were analyzed with SEM, X-Ray EDS, and XRD. Results T2 copper in the tropical marine atmosphere corroded uniformly. Its average corrosion speed decreased with the increase of the distance to the ocean surfaces and the time of exposing. The corrosion products were in a bilayer structure, the outer sphere of which was green Cu2(OH)3Cl; the inlayer was dense Cu2O.With the increase of the distance to the ocean surfaces and the time of exposing, the heavier the concentration of the Chloride Ion in the electrolytes on the surface of the samples and the more the Cu2(OH)3Cl in corrosion products of TS copper. Whereas, Cu2O was the most in the corrosion products. Conclusion There were significant differences between corrosion rate and salt spray deposition with offshore distance changes, salt spray deposition first increased and then decreased, with the maximum value in the 80 meters offshore; due to influences of the relative humidity of the atmosphere, the corrosion rate of T2 copper has the maximum value in the offshore 0 meters, a maximum at 80 meters offshore.