Y元素对铸态Mg-Y合金组织和性能的影响

Effect of Y on Microstructure and Properties of As-cast Mg-Y Alloy

采用金相显微镜、扫描电镜、能谱分析、X射线衍射物相分析、力学性能测试等方法,研究了5种Mg-Y合金铸态组织的相组成和力学性能,对比观察了随Y含量变化时合金的显微组织变化。结果表明,随着Y含量的增加,合金的微观组织由单一的α-Mg相变为α-Mg相和第二相Mg24Y5共存。Y含量为0.25%,2.5%时,微观组织为单一的α-Mg相,Y含量为5%,8%和15%时,微观组织由α-Mg相和第二相Mg24Y5组成。随着Y含量的增加,铸态Mg-Y系合金的抗拉强度和硬度增加,而伸长率降低。

The microstructure and mechanical properties of as-cast Mg-Y alloys with different Y addition were investigated by means of optical microscopy, scanning electron microscopy, X-ray diffractometry and EDS as well as tensile testing. The results reveal that with increase of Y element, the microstruc- ture of the alloy is changed from the single α-Mg phase to the coexist phases of the α-Mg and Mg24 Ys. The grain size in the alloy contained Y is refined with the Y content increased from 0.25% to 15%. With the increase of Y element, the tensile strength and hardness of Mg-Y are increased, while the elon- gation is decreased.