析出相对铝基牺牲阳极组织及电化学性能的影响  

Effects of Precipitation Phase on Microstructure and Electrochemical Performance of Aluminum-based Sacrificial Anode

作　　者：朱王科 李兰云[1] 董会[1] 韩燕 任康 ZHU Wangke;LI Lanyun;DONG Hui;HAN Yan;REN Kang(School of Materials Science and Engineering,Xi'an Shiyou University,Xi'an 710065,China;PetroChina Pipeline Engineering Technology Research Institute,Xi'an 710077,China)

机构地区：[1]西安石油大学材料科学与工程学院,陕西西安710065 [2]中国石油集团石油管工程技术研究院,陕西西安710077

出　　处：《热加工工艺》2021年第2期31-35,共5页Hot Working Technology

基　　金：国家自然科学基金资助项目(51904331);西安石油大学材料科学与工程省级优势学科项目(YS37020203);西安石油大学研究生创新与实践能力培养项目(YCS18212051)。

摘　　要：基于化学成分调控制备了两种不同的Al-Zn-In系阳极。在表征了析出相成分、分布的基础上,研究了析出相对阳极电化学性能的影响。采用扫描电镜(SEM)、能谱仪(EDS)表征析出相、腐蚀形貌及腐蚀产物。在污水储罐水质环境中进行了电化学性能测试,温度为室温(20℃)。结果表明:Al-Zn-In-Mg-Ti的第二相为富In相,呈细小颗粒状分布,Al-Zn-In-Mg-Sn的第二相为InSn2相,呈球状分布;在两种阳极的晶界处都形成了Al4Fe第二相,呈层片状分布。Al-ZnIn-Mg-Ti、Al-Zn-In-Mg-Sn的电流效率分别为65%、74%。宏观上均为典型的局部腐蚀形貌,微观上均发生了以析出相溶解为主的晶间腐蚀。Al-Zn-In-Mg-Ti点蚀严重,有径向腐蚀发展趋势,以富In相的优先溶解机理为主;Al-Zn-In-Mg-Sn较均匀,纵向腐蚀较为明显,以InSn2相的溶解-再沉积机理为主。Two different Al-Zn-In anodes were prepared based on chemical formation control.Based on characterizing the composition and distribution of the precipitated phase, the influences of the precipitated phase on the electrochemical performance of the anode were studied.Scanning electron microscope(SEM) and energy dispersive spectrometer(EDS) were used to characterize the precipitated phase, corrosion morphology and corrosion products.The electrochemical performance test was performed in the water environment of the sewage storage tank, and the temperature is room temperature(20 ℃). The results show that the second phase of Al-Zn-In-Mg-Ti is an In-rich phase,which is distributed in fine particles. The second phase of Al-Zn-In-Mg-Sn is In Sn2 phase, with a spherical distribution;in addition, a second phase of Al4 Fe appears at the grain boundaries of both anodes, which is distributed in a lamellar shape.The current efficiency of Al-Zn-In-Mg-Ti and Al-Zn-In-Mg-Sn is 65% and 74%, respectively.From a macro perspective, they are all typical local corrosion morphologies.Intergranular corrosion occurs mainly at the dissolution of the precipitated phase.Al-Zn-In-Mg-Ti has serious pitting corrosion and has a tendency of radial corrosion development. It is mainly based on the preferential dissolution mechanism of the In-rich phase;Al-Zn-In-Mg-Sn is relatively homogeneous, and the longitudinal corrosion is more obvious, mainly based on the dissolution-redeposition mechanism of In Sn2 phase.

关 键 词：牺牲阳极保护 电化学 第二相 晶间腐蚀 活化机理 

分 类 号：TG174.36[金属学及工艺—金属表面处理]