摘要
在500℃下制备压下量分别为0、25%、45%和80%的轧制WE43镁合金,并研究其在3.5 wt.%NaCl溶液中的腐蚀行为。采用光学显微镜(OM)、透射电子显微镜(TEM)和电子背散射衍射(EBSD)对轧制WE43合金的显微组织演变过程进行表征。结果表明,随着轧制压下量增加,合金的基面织构逐渐增强,晶粒尺寸逐渐减小。此外,仅压下量为45%的合金中存在弥散分布的动态析出相。浸泡实验和电化学实验结果表明,轧制WE43合金的耐蚀性由高到底的顺序为压下量45%>压下量80%>压下量25%>压下量0。压下量45%的合金具有最好的耐蚀性,主要原因是基体中大量弥散分布的析出相能促使致密腐蚀产物膜的形成。压下量为80%合金的腐蚀速率增加是析出相回溶至基体所致。析出相是轧制WE43合金腐蚀速率的主要影响因素,而晶粒尺寸、基面织构和形变孪晶是次要影响因素。
The corrosion behavior of WE43 alloy with different rolling reductions(0%,25%,45%,and 80%)at 500℃ was investigated in 3.5 wt.%NaCl solution.The microstructure evolution of the rolled WE43 alloy was characterized in detail by means of optical microscopy(OM),transmission electron microscopy(TEM)and electron back-scattered diffraction(EBSD).The results show that with increasing reductions,basal texture is gradually enhanced and grain size gradually decreases.Only the alloy with 45%reduction exhibits dispersed dynamic precipitates.Immersion and electrochemical measurements demonstrate the decreasing order of the corrosion resistance of the rolled WE43 alloy:45%reduction>80%reduction>25%reduction>0 reduction.The best corrosion resistance of the WE43 alloy with 45%reduction is mainly related to a large number of finely dispersed precipitates,which are capable of promoting the formation of a compact corrosion product layer.The increased corrosion rate of the sample with 80%reduction is induced by the re-solution of the majority of precipitates into the matrix.The grain size,basal texture and deformation twins have a limited effect on the corrosion resistance of rolled WE43 alloy compared with the precipitates.
作者
蔡勇
陈翌鹏
闫宏
单智伟
毛耀宗
陈荣石
Yong CAI;Yi-peng CHEN;Hong YAN;Zhi-wei SHAN;Yao-zong MAO;Rong-shi CHEN(School of Materials Science and Engineering,University of Science and Technology of China,Shenyang 110016,China;Shi-changxu Innovation Center for Advanced Materials,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;School of Materials Science and Engineering,Shandong University of Science and Technology,Qingdao 266590,China;State Key Laboratory for Mechanical Behavior of Materials,Xi’an Jiaotong University,Xi’an 710049,China;Shandong Key Laboratory of Advanced Aluminium Materials and Technology,Binzhou Institute of Technology,Binzhou 256606,China)
基金
supported by the National Natural Science Foundation of China (No.52271107)
the Bintech-IMR R&D Program,China (No.GYY-JSBU-2022-012)
the Natural Science Foundation of Shandong Province,China (No.ZR2021ME241)
the Natural Science Foundation of Liaoning Province,China (No.2020-MS-004).
关键词
稀土镁合金
轧制压下量
析出相
织构
晶粒尺寸
腐蚀行为
rare earth magnesium alloy
rolling reduction
precipitate
texture
grain size
corrosion hehavor
