稀有金属材料与工程
稀有金屬材料與工程
희유금속재료여공정
RARE METAL MATERIALS AND ENGINEERNG
2007年
2期
201-207
,共7页
肖葵%董超芳%李久青%李晓刚%魏丹
肖葵%董超芳%李久青%李曉剛%魏丹
초규%동초방%리구청%리효강%위단
镁合金%电偶腐蚀%大气腐蚀
鎂閤金%電偶腐蝕%大氣腐蝕
미합금%전우부식%대기부식
magnesium alloy%galvanic corrosion%atmospheric corrosion
在北京大气环境下,研究AM60镁合金和不同金属材料(碳钢、不锈钢、黄铜和铝合金)偶接的电偶腐蚀行为规律.研究表明,镁合金作为阳极发生不同程度的电偶腐蚀,通过1 a的北京大气环境下的暴露试验后,AM60 镁合金的电偶腐蚀效应由强到弱的顺序为:碳钢、黄铜、不锈钢和铝合金,其中镁合金与LY12铝合金偶接的电偶腐蚀效应最小.通过与其它地区室外暴晒的镁合金电偶腐蚀效应的对比,表明环境因素影响着镁合金的电偶腐蚀效应.同时阴极材料、试验时间、试样尺寸(偶接面积)和试验环境都会对镁合金电偶腐蚀效应产生影响.经1 a曝晒的AM60镁合金形成了具有保护性的腐蚀产物层阻碍了腐蚀发展.北京地区高自然降尘量导致金属表面湿润时间加大,从而加速了AM60 镁合金的电偶腐蚀.采用XRD 方法分析表面的腐蚀产物,用金相显微镜和扫描电镜(SEM)观察试样腐蚀后的表面形貌特征和腐蚀产物的结构,并用与之相连的能谱仪分析腐蚀产物中的元素组成.
在北京大氣環境下,研究AM60鎂閤金和不同金屬材料(碳鋼、不鏽鋼、黃銅和鋁閤金)偶接的電偶腐蝕行為規律.研究錶明,鎂閤金作為暘極髮生不同程度的電偶腐蝕,通過1 a的北京大氣環境下的暴露試驗後,AM60 鎂閤金的電偶腐蝕效應由彊到弱的順序為:碳鋼、黃銅、不鏽鋼和鋁閤金,其中鎂閤金與LY12鋁閤金偶接的電偶腐蝕效應最小.通過與其它地區室外暴曬的鎂閤金電偶腐蝕效應的對比,錶明環境因素影響著鎂閤金的電偶腐蝕效應.同時陰極材料、試驗時間、試樣呎吋(偶接麵積)和試驗環境都會對鎂閤金電偶腐蝕效應產生影響.經1 a曝曬的AM60鎂閤金形成瞭具有保護性的腐蝕產物層阻礙瞭腐蝕髮展.北京地區高自然降塵量導緻金屬錶麵濕潤時間加大,從而加速瞭AM60 鎂閤金的電偶腐蝕.採用XRD 方法分析錶麵的腐蝕產物,用金相顯微鏡和掃描電鏡(SEM)觀察試樣腐蝕後的錶麵形貌特徵和腐蝕產物的結構,併用與之相連的能譜儀分析腐蝕產物中的元素組成.
재북경대기배경하,연구AM60미합금화불동금속재료(탄강、불수강、황동화려합금)우접적전우부식행위규률.연구표명,미합금작위양겁발생불동정도적전우부식,통과1 a적북경대기배경하적폭로시험후,AM60 미합금적전우부식효응유강도약적순서위:탄강、황동、불수강화려합금,기중미합금여LY12려합금우접적전우부식효응최소.통과여기타지구실외폭쇄적미합금전우부식효응적대비,표명배경인소영향착미합금적전우부식효응.동시음겁재료、시험시간、시양척촌(우접면적)화시험배경도회대미합금전우부식효응산생영향.경1 a폭쇄적AM60미합금형성료구유보호성적부식산물층조애료부식발전.북경지구고자연강진량도치금속표면습윤시간가대,종이가속료AM60 미합금적전우부식.채용XRD 방법분석표면적부식산물,용금상현미경화소묘전경(SEM)관찰시양부식후적표면형모특정화부식산물적결구,병용여지상련적능보의분석부식산물중적원소조성.
This paper presents the galvanic corrosion behaviors of AM60 magnesium alloy coupled with variable materials(carbon steel, stainless steel, brass and aluminum alloy) in the outdoor atmosphere of Beijing. The correlations among mass variation, galvanic effect and atmospheric factors for AM60 magnesium alloy coupons were investigated. Surface morphologies were observed by scanning electron microscopy(SEM),and X-ray diffraction(XRD) was used to analyze the crystal corrosion products. The results showed that the AM60 magnesium alloy acted as anodic material when it coupled with tested metals. The arrangement order of galvanic effect from strong to little is carbon steel, brass, stainless steel and aluminum alloy after 12 months exposure in Beijing atmosphere. The atmospheric galvanic effect of magnesium alloys coupled with aluminum alloy is the least among the tested coupled alloys during any testing periods because the effective potential difference of the cathode(AM60)and anode(aluminum alloy)is the least for all of tested coupled alloys. The atmospheric galvanic effects in Beijing compared with other cities indicate that atmospheric environment is most important factor. The atmospheric galvanic effects for magnesium alloys are affected by cathode alloy, testing time, sample acreage and environment condition. And no intact and protective corroded products layer was formed to prevent further corrosion after 1 year exposure. The edge of AM60 coupon suffered harsh galvanic corrosion, which was limited by the existing of thin-film on the coupon surface. The high dust precipitation of Beijing could prolong the time of wetness on metal surface. So, the atmospheric corrosion of AM60 magnesium alloy coupled with different metals could be accelerated.