Nanocrystallization in a Zr 57 Ti 5 Cu 20 Al 10 Ni 8 bulk metallic glass
Nanocrystallization in a Zr 57 Ti 5 Cu 20 Al 10 Ni 8 bulk metallic glass
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Zr 57 Ti 5 Cu 20 Al 10 Ni 8 块状金属玻璃中的纳米晶化
DOI：
10.1080/09500830110078071
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
P. Guyot
中科院分区：
文献类型：
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作者：
Á. Révész;P. Ochin;P. Donnadieu;J. Simon;P. Guyot
通过差示扫描量热法、X射线衍射、透射电子显微镜和高分辨率电子显微镜研究了Zr 57 Ti 5 Cu 20 Al 10 Ni 8 块体金属玻璃向平衡热弛豫的第一阶段。这些联合实验排除了这种玻璃在结晶开始之前存在纳米级相分离的情况。结晶的第一步是初级类型，即它由纳米微晶在非晶基质中成核组成，它们以亚稳态平衡共存。非常高的成核率导致纳米复合结构具有约7 2 10 24 m -3 的3-4nm微晶的数密度，占据约15%的体积分数。讨论了这些特征以及等时或等温加热过程中观察到的结晶动力学。
The first stages of thermal relaxation towards equilibrium in a Zr 57 Ti 5 Cu 20 Al 10 Ni 8 bulk metallic glass have been studied by differential scanning calorimetry, X-ray diffraction, transmission electron microscopy and high-resolution electron microscopy. These coupled experiments rule out for this glass the existence of a phase separation on the nanometric scale preceding the onset of crystallization. The first step of crystallization is of the primary type, that is it consists of the nucleation of nanocrystallites in the amorphous matrix with which they coexist in metastable equilibrium. The very high nucleation rate leads to a nanometric composite structure with a number density of about 7 2 10 24 m -3 of 3-4nm crystallites, occupying a volume fraction of about 15%. These features, as well as the crystallization kinetics observed during isochronal or isothermal heating, are discussed.