کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1600845 | 1005177 | 2010 | 4 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Correlation between fragility and cooperativity in bulk metallic glass-forming liquids Correlation between fragility and cooperativity in bulk metallic glass-forming liquids](/preview/png/1600845.png)
It is known that the structural relaxation in supercooled liquid and glassy metals exhibit a non-Debye type relaxation behavior and a VFT-like temperature dependence. Such behaviors are often characterized by the exponent of the Kohlrausch–Williams–Watts (KWW) function and by the value of the fragility. In the present work, a quantity NB which gives the number of structural units involved in the thermally activated viscous flow is introduced to characterize the bulk metallic glass-forming liquids. NB is defined from the Bond Strength – Coordination Number Fluctuation (BSCNF) model of the viscosity. It is shown that NB can be a new indicator that quantifies the degree of cooperativity within the bulk metallic glass-forming liquids. For several bulk metallic glass-forming liquids, it is shown that the characteristic temperature ratio T0/Tg, NB, and the stretched exponent βKWW are mutually correlated through the fragility index m derived from the BSCNF model.
Journal: Intermetallics - Volume 18, Issue 10, October 2010, Pages 1796–1799