摘要
通过超声振动在7075合金中添加SiO_(2),原位生成Al_(2)O_(3)颗粒,利用X射线衍射仪(XRD)、自带能谱分析仪(EDS)的扫描电子显微镜(SEM)、透射电镜(TEM)、浸泡腐蚀实验和电化学测试实验对合金的微观组织、物相组成和耐腐蚀性能进行分析。结果显示,超声振动和Al_(2)O_(3)颗粒的原位生成可以细化合金的微观组织,将团聚的Al_(2)O_(3)颗粒分散均匀,且Al_(2)O_(3)颗粒可作为异质形核的核心,提高形核率。超声态Al_(2)O_(3(p))/7075合金主要由Al、Al_(2)O_(3)、Al_(7)Cu_(2)Fe、Al_(2)CuMg、Mg_(2)Zn相组成。相比于7075合金,超声态Al_(2)O_(3(p))/7075合金的失重腐蚀速率和析氢腐蚀速率下降,白色腐蚀产物减少,点蚀和晶间腐蚀程度减弱,自腐蚀电位(E_(corr))和点蚀电位(E_(p))上升,腐蚀电流密度(I_(corr))下降。超声态Al_(2)O_(3(p))/7075合金耐腐蚀性能提升是微观组织细化导致的腐蚀速率减缓和Al_(2)O_(3)颗粒原位生成导致的腐蚀电位升高的协调作用。
SiO_(2) was added into 7075 alloys by ultrasonic vibration to form Al_(2)O_(3)particles in situ.The microstructure,phase composition and corrosion resistance of the alloy were studied and analyzed by XRD,SEM,TEM,immersion corrosion tests and electrochemical tests,respectively.The results showed that ultrasonic vibration and in situ formation of Al_(2)O_(3)particles could refine the microstructure of the alloy and disperse the agglomerated Al_(2)O_(3)particles evenly,and Al_(2)O_(3)particles could be used as the core of heterogeneous nucleation to improve the nucleation rate.The Al_(2)O_(3(p))/7075 alloys with ultrasonic vibration are mainly composed of Al,Al_(2)O_(3),Al_(7)Cu_(2)Fe,Al_(2)CuMg and Mg_(2)Zn phases.Compared with the 7075 alloys,its weight loss corrosion rate and hydrogen evolution corrosion rate decreased,the white corrosion products reduced,and the degree of pitting and intergranular corrosion weakened.The self-corrosion potential(E_(corr))and pitting potential(E_(p))increased,and the corrosion current density(I_(corr))decreased.The improvement in the corrosion resistance of the Al_(2)O_(3(p))/7075 alloy with ultrasonic vibration is due to the coordination of the slowing corrosion rate caused by microstructure refinement and the increase in corrosion potential caused by the in situ formation of Al_(2)O_(3)particles.
作者
朱炳耀
贾小波
ZHU Bingyao;JIA Xiaobo*(Department of Mechanical and Automotive Engineering,Liuzhou City Vocational College,Liuzhou 545006,Guangxi,China;School of Microelectronics and Materials Engineering,Guangxi University of Science and Technology,Liuzhou 545006,Guangxi,China)
出处
《有色金属科学与工程》
CAS
北大核心
2023年第4期511-517,共7页
Nonferrous Metals Science and Engineering
基金
2020年度广西高校中青年教师科研基础能力提升项目(2020KY47011)。
