MgCl_2液滴对1420Al-Li合金腐蚀行为的研究  

Corrosion behavior of 1420Al-Li alloy under MgCl_2 solution drops

作　　者：李朝兴[1,2] 徐静[1] 李劲风[2] 邓畅光[1] 陈和兴[1] 

机构地区：[1]广州有色金属研究院,广东广州510650 [2]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《材料研究与应用》2013年第3期168-173,共6页Materials Research and Application

摘　　要：采用开尔文探针对1420Al-Li合金在初始浓度为0.1~1.0mol/L、体积为4μL的MgCl2液滴下的腐蚀行为进行了研究.结果表明,当MgCl2液滴初始浓度为0.1,0.3mol/L时,主要发生丝状腐蚀,其电位基线在-0.7^-0.8VSHE范围内,随着合金表面丝状腐蚀生长的停止与开始,出现电位突然增加而后立即下降的现象.当初始浓度增加到1mol/L时,主要发生孔蚀,随着孔蚀的不断形成与钝化,出现电位突降而后立即回复的现象.当液滴达到环境相对湿度后,随着MgCl2初始浓度的增加阴极极限电流减小,腐蚀速率降低.The corrosion behaviors of 1420Al-Li alloy under 4 μl MgClz solution drops with initial concen- tration of 0. 1~1.0mol/L were studied using a kelvin probe. The results showed that the filiform corro- sion mainly occurred when adding the MgCl2 drops with initial 0. 1mol/L and 0.3mol/L concentration, and the Volta potential baseline was at the range of --0. 7 to --0.8 VSHE. The electric potential increased sud- dently and then decreased immediately, which could be associated with the filiform corrosion growth stop and initiation. In the case of 1.0mol/L initial concentration, the meta-stable pitting corrosion mostly ap- peared, and the electric potential exhibitted a sudden decrease and then immediate recovery , which was as- sociated with the initiation and re-passivation of meta-stable pits. After the MgCl2 droplets reached the en- vironmental relative humidity, the cathodic limiting current associated with oxygen reduction was de- creased with increasing the initial MgCl2 concentration and the corrosion rate was decreased.

关 键 词：1420AL-LI合金 开尔文探针 腐蚀 MgCl2液滴 

分 类 号：TG171[金属学及工艺—金属表面处理]