非晶合金准静态循环加载过程滞弹性行为的反速率依赖性

Paradoxical Phenomena in Quasi-static Cyclic Loading-unloanding Compression Tests of Bulk metallic glasses

摘要:

在几何抑制条件下,对锆基块体非晶试样进行不同加载速率的室温准静态循环加载-卸载压缩实验。结果发现,合金存在明显的滞弹性行为、且滞后环面积与加载速率成反比,这与弹性应力诱发的微观结构演化有关。由于弹性应力诱发的微观结构演化与剪切带的空间增殖密切相关,因此循环加载能量消耗可以作为表征块体非晶合金剪切带空间增殖能力的参数。

Abstract:

The anelasticity behavior was investigated of Zr-based bulk metallic glasses in a geometrically constrained quasi-static cyclic loading–unloading compression tests. The results demonstrated that the dissipative energy during cycle loading was in inverse proportion to the cross-head displacement rate used, and the anelasticity behavior have close correlation with the elastic stress-induced microstructure evolution. The dissipative energy during cycle loading in BMGs could also be used as a parameter to characterize the spatial multiplication ability of shear bands. The larger dissipative energy implies the higher the spatial multiplication ability of shear bands.