直接空冷凝汽器20#钢与3004铝合金管材的模拟腐蚀实验研究  

Corrosion Characteristics of 20# Steel and Al-alloy 3004 Under Simulated Conditions for Air-cooled Condenser Tubes

作　　者：肖剑峰 朱志平 乔越 曹颉 田龙标 

机构地区：[1]长沙理工大学化学与生物工程学院电力与交通材料保护湖南省重点实验室,长沙410114

出　　处：《腐蚀科学与防护技术》2018年第1期41-48,共8页Corrosion Science and Protection Technology

基　　金：湖南省科技计划重点项目(2013GK2016);湖南省研究生科研创新项目(CX2016B415)~~

摘　　要：通过自建的一套空冷凝汽器模拟装置,在模拟其实际运行状况下对可选用的20#钢和3004铝合金管材进行了腐蚀挂片、动态极化曲线和动态电化学阻抗测试等实验,分析了介质温度、溶解氧、pH值和流速对两种材质腐蚀的影响,用SEM、EDS和XRD对腐蚀产物表面膜进行表征分析,由此探讨了其腐蚀机理。结果表明:3004铝合金的腐蚀速率比20#钢小1~2个数量级,且3004铝合金具有非常良好的阻抗特性、生成了均匀致密的耐蚀性氧化膜,而20#钢氧化膜疏松、易脱落、且有腐蚀坑;从技术经济角度上看,3004铝合金具有较好的应用前景。A device was set up to simulate the actual operation environment of ACC, and then with which, the corrosion behavior of Al-alloy 3004 and carbon steel 20# steel was comparatively studied with the emphasis in the influence of temperature, dissolved oxygen, pH and flow rate of the media on the corrosion of the two materials. After corrosion test, the surface of the two materials was characterized by scanning electron microscopy（SEM）, energy dispersive spectrometer（EDS）, and X-ray diffraction（XRD）. The results show that the corrosion rate of 20# steel steel is 10~100 times higher than that of Alalloy 3004, in other words, the protectiveness of the oxide scale formed on Al-alloy 3004 is better than that on the 20# steel, the former oxide scale is uniform and compact, while the later one is loose and apt to spalling. In general, Al-alloy 3004 has a better application prospect.

关 键 词：20#钢 3004铝合金 极化曲线 电化学阻抗 

分 类 号：TG174[金属学及工艺—金属表面处理]