摘要
在泰国曼谷地区对5083、6063和7020 3种铝合金进行为期1 a的暴晒实验,采用SEM、电化学实验、XPS和扫描Kelvin探针显微镜(SKPFM)对3种铝合金初期腐蚀形貌及腐蚀机理进行研究。结果表明:6063铝合金中Mg、Si、Fe等合金元素含量较少,腐蚀电位相对较高,约为-0.66 V (vs SCE),腐蚀产物膜较为致密,耐蚀性较好,在泰国曼谷地区的腐蚀速率约为0.7 g/(m^2·a)。7020铝合金含有较多Mg、Zn等合金元素,腐蚀电位约为-0.78 V (vs SCE),腐蚀最为严重,腐蚀速率约为3.26 g/(m^2·a)。3种铝合金均含有Mn、Si、Fe等合金元素,从而形成Fe-Si-Al或Fe-Si(Mn)-Al第二相,第二相表面电位高于基体225~280 mV,在大气环境中第二相作为阴极相,周围的基体Al优先溶解脱落,成为点蚀坑。
With the rapid development of rail transit, high-speed trains are gradually exported to Southeast Asian countries. Aluminum alloy is widely used as a structural material such as train body and rail beam in high-speed trains, so that it is important to study the corrosion behavior of different aluminum alloy in Southeast Asia. The exposure test was conducted on 5083, 6063 and 7020 aluminum alloys in Bangkok, Thailand for 1 a. SEM, XPS, electrochemical experiment and scanning Kelvin probe force microscopy(SKPFM) were used to study the corrosion morphology and corrosion mechanism of different aluminum alloys. The results showed that the corrosion potential of 6063 aluminum alloys were relatively high, about-0.66 V(vs SCE), and the corrosion morphologies were relatively mild, which was due to less alloy elements such as Mg, Si and Fe in the 6063 aluminum alloys. The corrosion rate of 6063 aluminum alloys in Bangkok, Thailand was about 0.7 g/(m^2·a). 7020 aluminum alloy contains more Zn elements, and the corrosion potential was about-0.78 V(vs SCE). The corrosion rate was the highest,about 3.26 g/(m^2·a). The second phase of Fe-Si-Al or Fe-Si(Mn)-Al formed in the microstructure of the three aluminum alloys. The surface potential of the second phase was higher than that of the matrix,about 225~280 mV. In the atmospheric environment, the second phase acted as the cathode phase, and the surrounding matrix Al dissolved preferentially. The second phase fell off and formed a pit.
作者
王力
董超芳
张达威
孙晓光
Thee Chowwanonthapunya
满成
肖葵
李晓刚
WANG Li;DONG Chaofang;ZHANG Dawei;SUN Xiaoguang;Thee Chowwanonthapunya;MAN Cheng;XIAO Kui;LI Xiaogang(Corrosion and Protection Center,University of Science and Technology Beijing,Beijing 100083,China;CRRC Qingdao Sifang Co.,Ltd.,Qingdao 266111,China;s3 Faculty of International Maritime Studies,Kasetsart University,Chonburi 20230,Thailand;School of Materials Science and Engineering,Ocean University of China,Qingdao 266100,China)
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2020年第1期119-128,共10页
Acta Metallurgica Sinica
基金
国家重点研发计划项目No.2017YFB0702300
国家自然科学基金项目No.51871028
国家材料环境腐蚀平台项目No.2005DKA10400~~
关键词
铝合金
泰国曼谷
大气腐蚀
点蚀
aluminum alloy
Bangkok Thailand
atmospheric corrosion
pitting
