时效工艺对Al-Zn-Mg-Sc-Er合金显微组织与耐蚀性能的影响  

Effects of Aging Process on the Microstructure and Anti-Corrosion Properties of Al-Zn-Mg-Sc-Er Alloys

作　　者：汤中英 邢清源 杨守杰 TANG Zhongying;XING Qingyuan;YANG Shoujie(Institute of Corrosion Science and Technology,Guangzhou 510000,China;AECC Beijing Institute of Aeronautical Materials,Beijing 100095,China)

机构地区：[1]广东腐蚀科学与技术创新研究院,广东广州510000 [2]中国航发北京航空材料研究院,北京100059

出　　处：《材料保护》2024年第9期154-160,共7页Materials Protection

摘　　要：Al-Zn-Mg合金是可热处理强化铝合金,研究不同合金时效工艺对其组织与性能的影响是铝合金研究的主要方向之一。基于室温拉伸、剥落腐蚀的试验方法和极化曲线、电化学阻抗谱、透射电镜等分析手段,研究不同时效工艺对Al-Zn-Mg-Sc-Er合金力学与耐腐蚀性的影响。结果表明:时效制度T6、T7-LS、T7-SL处理后Al-Zn-Mg-Sc-Er合金的室温拉伸性能依次降低,剥落腐蚀评级依次为EA、P、N级;极化曲线及电化学阻抗谱测试分析显示,随合金时效程度的加深,腐蚀电流密度降低,发生电化学腐蚀时电荷转移电阻增大,合金的耐腐蚀性能提高;影响合金耐腐蚀性能的主要因素为析出相的种类、尺寸、分布及无沉淀析出带(PFZ)的宽度。Al-Zn-Mg alloys are aluminum alloys that can be strengthened through heat treatment.Investigating the effects of various alloy aging processes on the microstructure and properties is one of the primary research directions in aluminum alloy studies.In this study,the effects of different aging processes on the mechanical properties and corrosion resistance of Al-Zn-Mg-Sc-Er alloys were investigated based on room-temperature tensile tests,exfoliation corrosion tests,polarization curves,electrochemical impedance spectroscopy(EIS)and transmission electron microscopy(TEM).Results showed that after treatment with aging schedules T6,T7-LS and T7-SL,the room-temperature tensile properties of Al-Zn-Mg-Sc-Er alloys decreased sequentially,while the exfoliation corrosion ratings were EA,P and N,respectively.Analysis of polarization curves and electrochemical impedance spectroscopy revealed that as the aging degree of the alloy increased,the corrosion current density decreased,and the charge transfer resistance during electrochemical corrosion increased,leading to improved corrosion resistance.The main factors affecting the corrosion resistance of the alloy were identified as the type,size,distribution of precipitates and the width of the precipitate-free zone(PFZ).

关 键 词：Al-Zn-Mg-Sc-Er合金 时效工艺 微观组织 耐蚀性 剥落腐蚀 

分 类 号：TG156.9[金属学及工艺—热处理]