挤压态EW75稀土镁合金在沈阳工业大气环境中的腐蚀行为研究
Corrosion Behavior of Extruded EW75 Mg-alloy in Shenyang Industrial Atmosphere
孙硕 1代珈铭 1宋影伟 2艾彩娇3
作者信息
- 1. 沈阳工业大学环境与化学工程学院 沈阳 110870
- 2. 中国科学院金属研究所核用材料与安全评价重点实验室 沈阳1100163
- 3. 滨州魏桥国科高等技术研究院山东省先进铝基材料与技术重点实验室滨州 256600
- 折叠
摘要
将挤压态EW75镁合金长期暴露在沈阳典型工业大气中,采用扫描电镜观察其在大气中暴晒不同周期后的表面和截面微观腐蚀形貌,并采用Raman光谱及EDS能谱分析腐蚀产物化学成分.结果表明,工业大气中的可溶性尘土会在挤压态EW75镁合金表面沉积,形成圆形的腐蚀产物,对下面的镁基体有较好的保护性;由于挤压态EW75镁合金中析出相尺寸小,且与镁基体之间的电位差较小,微电偶作用较弱,发生均匀腐蚀.此外,沈阳的季节变化对镁合金的腐蚀影响很大,与低温、低湿的冬季相比,挤压态EW75镁合金在高温高湿的夏季腐蚀率明显更高.
Abstract
Mg-alloys as the lightest metallic structural materials have many excellent properties,but their corrosion resistance is poor.Thus the corrosion behavior of Mg-alloy in different service conditions need to be acquired.Especially,the composition of pollutants and meteorological factors in different atmo-spheric environments may affect the corrosion behavior of Mg-alloys.In this paper,the corrosion behav-ior of the extruded EW75 Mg-alloy in Shenyang industrial atmosphere was investigated by atmospheric exposure at Shenyang atmospheric test station located at 123°26'east and 41°46'north.After exposure for different durations,the test alloys were characterized by means of SEM,EDS and Raman spectrosco-py in terms of their surface and cross sectional morphology and the chemical composition of corrosion products.The results show that the dusts containing soluble salts in the industrial atmosphere were de-posited on the surface of the extruded EW75 Mg-alloy and form round-shaped corrosion products,which show good protection for the corresponding magnesium matrix;the potential difference between the fine precipitation phases and α-Mg is low,which exhibits weak micro-galvanic effect,resulting in the formation of uniform corrosion.In addition,the corrosion rate of Mg-alloys in Shenyang atmosphere is greatly influ-enced by seasonal variations.Compared with the low temperature and low humidity winter,the corrosion rate of the extruded EW75 Mg-alloy is significantly higher in the high temperature and high humidity sum-mer.
关键词
稀土镁合金/大气腐蚀/耐蚀性/工业大气/微电偶腐蚀Key words
rare-earth Mg-alloy/atmospheric corrosion/corrosion resistance/industrial atmosphere/micro-galvanic corrosion引用本文复制引用
基金项目
国家自然科学基金(52171086)
国家科技基础条件平台建设项目(2005DKA10400-15-Z04)
魏桥合作项目(GYY-JSBU-2022-005)
出版年
2024
NETL
NSTL
维普
万方数据