Effect of Al Addition on the Mechanical Properties and Microstructure of Zr35Ti30Cu7.5Be27.5 Bulk Metallic Glass

摘要:

利用单轴压缩试验研究了用部分Al替代Zr对Zr35-xTi30Cu7.5Be27.5Alx (x=0，1，1.5，2，2.5，5，at%) 块体金属玻璃力学性能的影响。研究表明，当添加Al含量为1.5 at%和2 at%时，所得到的块体金属玻璃的压缩塑性从0.95% (x=0) 分别提高至15.10% (x=1.5) 和3.45% (x=2)。利用扫描电子显微镜 (SEM) 对金属玻璃样品的断裂形貌进行了表面分析。利用透射电子显微镜 (TEM) 对不同Al含量的块体金属玻璃试样进行了微观结构表征，结果显示，Al含量为1.5 at %和2 at %的金属玻璃样品的微观结构呈现出了纳米级别的“微观不均匀性”。最后，结合临界剪切应力 (CSS) 讨论了微观结构与塑性变形行为之间的关联性

Abstract:

The effect of partial substitution of Al for Zr on the mechanical properties of Zr35-xTi30Cu7.5Be27.5Alx (x=0, 1, 1.5, 2, 2.5, 5, at%) bulk metallic glasses were studied by uniaxial compression test. The results showed that the compressive plasticity can be greatly improved from 0.95% (x=0) to 15.10% (x=1.5) and 3.45% (x=2) in Zr35Ti30Cu7.5Be27.5 bulk metallic glass. The fracture morphologies of the Zr35-xTi30Cu7.5Be27.5Alx bulk metallic glasses were characterized by means of scanning electron microscope (SEM). Transmission electron microscope (TEM) was employed to investigate the microstructures of the bulk metallic glasses containing different amounts of Al. It is found that the enhanced compressive plasticity could be attributed to the nanoscale heterogeneity in the bulk metallic glasses. The effect of Al addition on the microstructure and deformation behavior of the Zr-based bulk metallic glasses was discussed in terms of different critical shear stress (CSS).