η相在Al-Zn-In-Mg-Ti牺牲阳极合金中的活化作用  

Activation Effects of η Precipitates in the Al-Zn-In-Mg-Ti Sacrificial Anode Alloys

作　　者：马景灵[1,2] 文九巴[1] 卢现稳[1] 

机构地区：[1]河南科技大学材料科学与工程学院 [2]兰州理工大学材料科学与工程学院

出　　处：《特种铸造及有色合金》2010年第1期18-21,共4页Special Casting & Nonferrous Alloys

基　　金：洛阳市科技攻关项目(0701025A)

摘　　要：采用扫描电镜、透射电镜、X射线衍射、电化学性能测试等方法,研究了Al-5Zn-0.02In-1Mg-0.05Ti牺牲阳极合金中析出相的腐蚀行为。结果表明,该合金主要含η-MgZn2析出相。η析出相相对α-Al基体呈阳极相,在3.5%的NaCl溶液中与α-Al基体组成微腐蚀电池,引起析出相自身溶解。溶解的Zn2+沉积在蚀坑周围,增加这些位置氧化膜的缺陷,促使氧化膜脱落。该牺牲阳极合金的溶解是以η析出相为活化中心,由此向外扩展,引发合金全面溶解。Activation effects of η precipitates in the Al-5Zn-0.02In-1Mg-0.05Ti sacrificial anode alloy were examined by SEM(scanning electron microscope),TEM(transmission electron microscope),XRD(X-ray diffraction)and electrochemical properties testing.The results reveal that the main precipitates are the MgZn2 phase(η phase).The η precipitates are taken as anodic phase to form a micro-corrosion cell with α-Al matrix in 3.5%NaCl solution,leading to the self-dissolution of the precipitates.Dissolved Zn2+ is deposited around the pit to enhance the occurrence of oxidized defects and to promote the exfoliation of oxidization film.The η phases are acted as the activation center for alloy dissolution,resulting in the whole dissolution of the alloy by extending outward.

关 键 词：牺牲阳极合金 η析出相 腐蚀 活化 

分 类 号：TG174.41[金属学及工艺—金属表面处理]