TY - JOUR
T1 - Inhomogeneous structure and glass-forming ability in Zr-based bulk metallic glasses
AU - Sun, Yong Li
AU - Qu, Dong Dong
AU - Sun, Ya Juan
AU - Liss, K. D.
AU - Shen, Jun
N1 - Funding Information:
This work was supported by the National Natural Science Foundation of China (NSFC) under Grant Nos. 50771040 and 10732010 , and the Heilongjiang Provincial Natural Science Foundation (Contract no. JC200806 ).
PY - 2010/1/1
Y1 - 2010/1/1
N2 - Recently, a series of quaternary Zr-based bulk metallic glasses (BMGs), i.e., Zr53Cu18.7Ni12Al16.3, Zr51.9Cu23.3Ni10.5Al14.3 and Zr50.7Cu28Ni9Al12.3, have been developed and their glass-forming ability (GFA) increases with Cu concentration. In this work, atomic structures of the three BMGs were rebuilt by reverse Monte Carlo simulations based on the reduced pair distribution functions measured by high energy X-ray diffraction. The results show that a certain amount of substitution of short Zr-Cu, Cu-Cu pairs with long Zr-Zr and Zr-Al pairs enhances the local denser packing of Kasper polyhedral centered by Zr and Al atoms. A cell sub-divided method is proposed to describe the fluctuation of local number density which is found to follow the normal distribution function. The largest possible free volume in the three alloys is found to approaches to 3.8 Å. For the three alloys, the enhancement of GFA with increasing Cu content is due to the increase in the fluctuation degree of local density instead of the dense packing.
AB - Recently, a series of quaternary Zr-based bulk metallic glasses (BMGs), i.e., Zr53Cu18.7Ni12Al16.3, Zr51.9Cu23.3Ni10.5Al14.3 and Zr50.7Cu28Ni9Al12.3, have been developed and their glass-forming ability (GFA) increases with Cu concentration. In this work, atomic structures of the three BMGs were rebuilt by reverse Monte Carlo simulations based on the reduced pair distribution functions measured by high energy X-ray diffraction. The results show that a certain amount of substitution of short Zr-Cu, Cu-Cu pairs with long Zr-Zr and Zr-Al pairs enhances the local denser packing of Kasper polyhedral centered by Zr and Al atoms. A cell sub-divided method is proposed to describe the fluctuation of local number density which is found to follow the normal distribution function. The largest possible free volume in the three alloys is found to approaches to 3.8 Å. For the three alloys, the enhancement of GFA with increasing Cu content is due to the increase in the fluctuation degree of local density instead of the dense packing.
KW - Amorphous metals
KW - Metallic glasses
KW - Monte Carlo simulations
UR - http://www.scopus.com/inward/record.url?scp=70450183953&partnerID=8YFLogxK
U2 - 10.1016/j.jnoncrysol.2009.09.021
DO - 10.1016/j.jnoncrysol.2009.09.021
M3 - 文章
AN - SCOPUS:70450183953
VL - 356
SP - 39
EP - 45
JO - Journal of Non-Crystalline Solids
JF - Journal of Non-Crystalline Solids
SN - 0022-3093
IS - 1
ER -