Characterization of Free Volume in a Bulk Metallic Glass Using Positron Annihilation Spectroscopy
Characterization of Free Volume in a Bulk Metallic Glass Using Positron Annihilation Spectroscopy
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DOI：
10.1557/jmr.2002.0171
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发表时间：
2002-05
影响因子：
2.7
通讯作者：
K. Flores;D. Suh;R. Dauskardt;P. Asoka-kumar;P. Sterne;R. Howell
中科院分区：
文献类型：
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作者：
K. Flores;D. Suh;R. Dauskardt;P. Asoka-kumar;P. Sterne;R. Howell
金属玻璃的自由体积对原子驰豫过程有重要影响，尽管目前还缺乏对自由体积位置的性质和分布的详细了解。用正电子湮没谱研究了Zr-Ti-Ni-Cu-Be大块金属玻璃经塑性应变和原子氢阴极充电后的自由体积。多项技术表明，应变样品有更多的开放体积，而适度的充氢导致自由体积减少。研究还表明，自由体积与锆和钛有关，而与镍、铜和铍的关系不大。塑料的应变导致了轻微的化学重新排序。
The free volume of metallic glasses has a significant effect on atomic relaxation processes, although a detailed understanding of the nature and distribution of free volume sites is currently lacking. Positron annihilation spectroscopy was employed to study free volume in a Zr–Ti–Ni–Cu–Be bulk metallic glass following plastic straining and cathodic charging with atomic hydrogen. Multiple techniques were used to show that strained samples had more open volume, while moderate hydrogen charging resulted in a free volume decrease. It was also shown that the free volume is associated with zirconium and titanium at the expense of nickel, copper, and beryllium. Plastic straining led to a slight chemical reordering.