摘要
为了得到附着力好、耐腐蚀性强的稀土镁合金,在353 K油浴条件下,采用循环伏安法分别研究了Gd(Ⅲ)、Mg(Ⅱ)、Co(Ⅱ)在氯化胆碱-尿素低温熔盐体系中的电化学行为。结果表明:Co(Ⅱ)→Co为一步不可逆反应,其在Pt电极的传递系数为0.41,扩散系数为1.32×10^(-6)cm^2/s,Mg(Ⅱ)、Gd(Ⅲ)在此体系中不能单独还原为单质,可被Co(Ⅱ)诱导共沉积。由恒电位法电沉积得到的Gd-Mg-Co合金中Gd的含量随沉积电位、沉积时间、Gd^(3+)/Mg~)(2+)/Co^(2+)浓度比的改变而改变,在-1.15 V电位下,Gd^(3+)/Mg~)(2+)/Co^(2+)摩尔比为4∶3∶4、沉积20 min时,得到表面均匀的黑色合金膜。在此沉积条件下得到的合金膜经扫描电镜(SEM)、X射线衍射仪(XRD)、能谱仪(EDX)等手段进行形貌、成分分析可知,此合金膜为非晶态,在碱性溶液中具有较好的耐腐蚀性能,合金膜中Gd的质量分数高达62.41%。
In order to get rare earth magnesium alloy with good adhesion and corrosion resistance, cyclic vohammetry was used to study the electrochemical behaviors of Gd （ III） , Mg （ II ） , Co （ II ） in chlorcholine - urea low - temperature molten salt systems under 353 K oil bath condition. Results showed that the reaction of Co（II ） transforming into Co was irreversible, which had transfer coefficient of 0.41 on the Pt electrode and diffusion coefficient of 1.32×10-6 cm^2/s. Mg（ II ） and Gd（ III） could not be reduced and deposited separately, while were always induced co-deposition by Co（ II ）. In addition, the Gd content in Gd-Mg-Co alloy deposited by potentiostatic method changed as the deposition potential, deposition time, and the concentration ratio of Gd3＋/Mg2＋/Co2＋. When the molar ratio of Gd3＋/Mg2＋/Co2＋ was 4 ： 3 ： 4 and deposi- tion time was 20 min, the dense black alloy film with uniform surface was obtained at the potential of -1.15 V. By using scanning electron microscope （SEM） , X-ray diffractometer （XRD） and energy dispersive spectrometer （EDX） to analyze the morphology and composition, the obtained alloy film with amorphous phase had good corrosion performance in alkaline solution, and the mass content of Gd in the alloy fihn reached up to 62.41%.
作者
李苗
何敏
陈必清
LI Miao;HE Min;CHEN Bi-qing(College of Chemistry and Chemical Engineering, Qinghai Normal University, Xining 810008, China)
出处
《材料保护》
CAS
CSCD
北大核心
2018年第3期50-55,共6页
Materials Protection
基金
青海基础研究计划项目(2016-ZJ-753)
国家自然基金项目(21553002)资助
