摘要
采用光学显微镜(OM)、扫描电镜(SEM)、透射电镜(TEM)、万能材料试验机和电化学试验等方法,研究了Nd含量对Mg-2Zn-0.2Sr-0.6Zr-xNd(质量分数/%,x=0,1,2)合金微观组织、力学性能及耐蚀性能的影响。结果表明,添加Nd可以细化晶粒,形成颗粒状均匀分布的Mg-Zn-Nd第二相(T相),且第二相体积分数随着Nd含量的增加而增加。室温拉伸试验结果表明,微量的Nd可以提升镁合金的抗拉强度和屈服强度,但伸长率略有下降。利用Hank’s溶液研究合金的降解行为,结果发现,当x=0、1、2时,Mg-2Zn-0.2Sr-0.6Zr-xNd合金的腐蚀速率分别为0.49、0.39、1.12 mm/a。添加1%的Nd的合金耐蚀性能有所提升,而添加2%的Nd的合金耐蚀性能大幅下降。总体来看,Mg-2Zn-0.2Sr-0.6Zr-1Nd合金具有最佳的力学和耐蚀性能。
The microstructure, mechanical properties and corrosion resistance of Mg-2 Zn-0.2 Sr-0.6 Zr-xNd(x=0, 1, 2, weight fraction) alloy were investigated by optical microscope(OM), scanning electron microscope(SEM), transmission electron microscope(TEM), universal material testing machine and electrochemical experiments. Microstructure experiments show that the addition of Nd can refine the grain size and the granular Mg-Zn-Nd second phase(T phase) which grows up with the increase of Nd content is uniformly distributed. Tensile tests at room temperature show that trace amount of Nd can improve the yield strength and tensile strength, however the elongation is decreased slightly with the increase of Nd content. The degradation behavior of Mg-2 Zn-0.2 Sr-0.6 Zr-xNd alloy was analyzed by using Hank’s solution. The results show that the corrosion rate of Mg-2 Zn-0.2 Sr-0.6 Zr-xNd(x=0,1,2) is 0.49 mm/a, 0.39 mm/a and 1.12 mm/a, respectively. With 1%Nd addition, corrosion resistance of the alloy can be improved. However, the corrosion resistance of the alloy with 2%Nd is decreased significantly. In general, Mg-2 Zn-0.2 Sr-0.6 Zr-1 Nd has the satisfied combination of mechanical properties and corrosion resistance.
作者
王祯寅
徐玉召
李静媛
Wang Zhenyin;Xu Yuzhao;Li Jingyuan(Beijing Advanced Innovation Center for Materials Genome Engineering;School of Materials Science and Engineering,University of Science and Technology Beijing)
出处
《特种铸造及有色合金》
CAS
北大核心
2021年第10期1238-1244,共7页
Special Casting & Nonferrous Alloys
基金
国家自然科学基金资助项目(52027805)。
