摘要
研究了Zn含量对经过模拟钎焊处理的3003铝合金显微组织、力学性能和电化学性能的影响规律。透射电镜(TEM)结果表明:Zn合金化对合金微观组织尤其是析出相的形貌影响不明显,三种合金的析出相均为较规则的近球形颗粒,Zn含量增大会使析出相的密度增大。用能谱分析仪(EDS)分析了含Zn铝合金的基体和析出相的成分,结果表明基体中含有Zn元素,而析出相中不含Zn元素,证明Zn主要是以固溶体的形式而非相的形式存在于合金中。拉伸试验结果表明:随着Zn含量的增加,合金的拉伸强度会略微提高,延伸率略微下降。用扫描电镜(SEM)对拉伸断口形貌进行了分析,结果表明合金的断裂形式为典型的韧性断裂。在0.5%NaCl溶液中的电化学实验结果表明,当合金中添加质量分数为1.5%的Zn元素,合金的腐蚀电位明显负移,这不利于合金的抗蚀性。随着Zn的质量分数从1.5%增加到1.8%,腐蚀电位变化较轻微,说明Zn含量的增加使合金的腐蚀电位向负方向移动,但是随着Zn含量的增加,这种影响越来越弱。同时,随着Zn含量的增加,腐蚀电流密度逐渐增大,说明Zn含量的增加使合金的抗腐蚀性能减弱。
In this paper,effect of Zn content on the microstructure and properties of simulated brazing 3003 Al alloy was investigated.Transmission electron microscopy（TEM） experiments revealed that the influence of Zn alloying on the microstructure of alloy,especially the morphology of precipitate phase,was not distinct.The precipitates in three alloys are regular and near spherical particles.However,an increase of Zn content increases the density of precipitates in alloys.The composition of both the matrix and precipitates of alloys was analyzed using Energy Dispersive X-Ray Spectroscopy（EDS）.The results indicate that the alloy matrix contains Zn element but the precipitates are Zn-free,indicating that Zn element in the alloys exists in the form of solid solution rather than compound form.Tensile testing results show that,with increase of the Zn content,the tensile strength slightly increases but the elongation decreases slightly.The scanning electron microscopy（SEM） observation of fracture surfaces reveals that all alloys demonstrate a typical ductile fracture.The electrochemical testing results indicate that Zn addition to the 3003Al alloy has a great impact on the corrosion potential of simulated brazing alloys in 0.5% NaCl solution.The corrosion potential of alloy alloying with 1.5wt% Zn shifts apparently to negative direction by 65 mV,which is harmful to corrosion resistance.When the Zn content increases from 1.5 wt% to 1.8 wt%,the potential of alloy slightly decreases by only 2 mV.This indicates that the corrosion potential shifts to negative direction with addition of Zn element to the alloys but the negative effect decreases with increase of the Zn content.At the same time,the corrosion current density increases with increase of the Zn content,which proves that the addition of Zn decrease the corrosion resistance of the alloy.
出处
《上海有色金属》
CAS
2012年第1期1-6,共6页
Shanghai Nonferrous Metals
基金
上海市高新技术产业化重大项目
关键词
3003铝合金
Zn元素
微观组织
力学性能
电化学性能
腐蚀
3003 Al alloy
Zn element
microstructure
mechanical properties
electrochemical properties
corrosion
