·528· 北京科技大学学报 2002年第5期 Foum,1984,7(4):211 7李久青，田虹，卢翠英等，铝和铝合金稀土转化膜碱性 3 Mansfeld F,LinS,Kim S,et al.Corrosion protection of Al 成膜技术).腐蚀科学与防护技术，1998,10(2：98 alloy and Al-based metal matrix composites by chemical 8 Hinton B R W,Arnott DR,Ryan NE.Cerium conversion passivation [J].Corrosion,1989,45(8):615 coatings for the corrosion protection of aluminum [J. 4 Davenport A J,Isaacs HS,Kendig M W.X-ray absorp- Metals Forum,1986(9):162 tion study of cerium in the passive film on aluminium [J]. 9 AldykewiczA J Jr,Isaacs HS,Davenport A J.The inves- J Electorchem Soc,1989,136(6):1873 tigation of cerium as a cathodic inhibitor for aluminum- 5 Mansfeld Florian B,Shih Hong,Wang You.Method for copper alloys [J].J Electrochem Soc,1995(142):3342 Creating a Corrosion-Resistant Aluminium Surface [P]. 10 Scully JR,Knight TO,Buchheit R G,et al.Electrochem- Patent US,No.5194138,1993 ical characteristics of the Al:Cu,Al,Ta and Al Zr intermet- 6刘伯生，抑制铝合金腐蚀的新颖转化膜).国外金 allic phases and their relevance to the localized corrosion 属加工，1992(1少27 of Al alloys [J].Corrosion Science,1993(35):185 Forming Process of Rare Earth Conversion Coatings on LY12 Al Alloy GAO Tianzhu,LI Jiuqing Material Science and Engineering School,UST Beijing,Beijing 100083,China ABSTRACT A Cu/Al galvanic couple was used to simulate the electrochemical behavior of LY12 alumin- um alloy in cerium salt solutions.The galvanic current decreased with time from 0.08 mV to 0.005 mV after immersion in the solutions,which indicates that the corrosion was inhibited.The galvanic potential moved negatively,which shows the cerium film inhibits the cathodic reaction.After 8 h of immersion,a yellow layer was formed on the copper of the galvanic couple.SEM,EDX anslyses show that the layer has a dry mud ap- pearance and contains a mess of Ce. KEY WORDS galvanic couple;aluminum alloy;rare-earth conversion coating. 5 28 . 北 京 科 技 大 学 学 报 2朋 2 年 第 s 期 F o r u r n , 19 8 4 , 7 (4 ) : 2 1 1 3 M an s fe l d F, L in S , K i m S , e t a l . C o mr s i o n Pr o t e ct ion o f A I a lloy an d A I 一 b a s e d m e at l m a tir x e om P o s iet s by c h e m i e a l P a s s i v at i o n [ J] . C o or s i o n , 1 9 89 , 4 5 ( 8) : 6 15 4 D va e nP 0 rt A J , I s ac s H S , K e n d ig M W. X 一 r a y ab s o pr - t i o n stU dy o f c e ir nUI in ht e P as s ive if lm on a l um in ium [J ] . J E l e oCt cr h e m S 0 e , 19 89 , 13 6 ( 6 ) : 1 8 7 3 5 M an s fe ld F ot ir an B , S h止 oH gn , V自叮g 、 or u . Me t h o d for C er at in g a C or s ion 一 eR s i s st nL t A l u m诚um S u r fa c e [P ] . Pat e in U S , N o . 5 1 9 4 1 3 8 , 1 9 9 3 6 刘 伯生 . 抑 制铝合金腐蚀 的新 颖转 化膜 [J] . 国外金 属加 工 , 1 9 9 2 ( l ) : 2 7 7 李久青 , 田 虹 ,卢翠英等 . 铝和铝 合金稀 土转化膜碱性 成 膜技术 [J] . 腐蚀科学 与 防护 技术 , 19 98 , 10 (2 :) 98 8 H i n t o n B R W, A m o tt D R , yR an N E . C e ir um c o vn e sr i o n e o at i n g s for het c o mr s i o n P r oet ot i o n o f al um i num [J ] . M e t a l s F o r u r n , 19 86 (9 ) : 16 2 9 A I勿 ke w i c z A J rJ, I s娜 s H S , D va e nP o rt A J . hT e in v e s - t ig at i o n o f e e ir um a s a e hat o id e Ihn ib i t o r for ia um l n切m - e 0 PP e r al loy s [J ] . J E l e c tr o c h e m Soc , 1 9 9 5 ( 1 4 2 ) : 3 3 4 2 10 S e u l ly J 凡 肠lgh t T O , B那h e it R G , et a l . E l e e otr e h e m - i e a l e h a r a c et ir st i c s o f l h e A 1 2 C u , A 1 3 aT an d A 13Z r int e n n et - ia li e hP as e s an d ht e ir er l e v an e e ot ht e lco ia 吮d e o mr s i o n o f A I a ll o y s [J ] . C o lr 勺 s ion S e i e n e e , 19 9 3 ( 35 ) : 1 8 5 F o mr ing P or e e s s o f R a r e E a rt h C o vn e r s i o n C o at i n g s o n l笼 12 A I A ll o y G 搜口 厂沁” 艺六u, LI iJ u q ign M at e r ial S c i cen e 阳 d E n g ien r i n g S c h o o l , U S T B e ij in g , B e ij ign 10 0 0 83 , C h in a A B S T R A C T A C 侧A I g a l v a in e e o uP l e w a s u s e d t o s im u l aet ht e e l e e otr e he m i e a l b e h va i o r o f YL 12 a l um in - um al loy in e e r l u rL n s alt s o l u t l o n s . hT e gVal an i e c u 比 e nt d e e er a s e d w iht tha e fr om 0 . 0 8 m V ot o 乃0 5 m V a ft e r In u n e r s i o n in ht e so lut ion s , w h l e h in id c aet s ht a t t h e e o or s i o n w a s i刊比b iet d . hT e g al v an i e P o t e nt i a l m o ve d n e g at i v e ly, w h l e h s h ow s t h e e e r l U比 n if lm i n h lb it s het c a th o d i e er ac ti on . A ft e r 8 h o f u r 匡n e r s i o n , a y e ll o w lay er w a s fo mr e d o n het e o p e r o f ht e g a l v 耐 e e o uP l e . S E M , E D X an s ly s e s s bo w ht a t 阮 lay er ha s a 山下 m 回 aP - P e ar an e e a n d c o n at in s a me s s o f C e . K E Y W O R D S g a l v an i e e o uP l e : a l um l n um a ll o y : r ar e 一 e 别rt h e o n v e r s ion e o at i n g