Correlation between mechanical and thermodynamic properties for La-Ce-Ni-Cu-Al high-entropy metallic glasses  

作　　者：Lin Wu Yong Zhao Jun-jun Li Ji-li Wu Bo Zhang 

机构地区：[1]Institute of Amorphous Matter Science and School ofMaterials Science and Engineering, Hefei University of Technology, Hefei 230009, Anhui, China

出　　处：《Journal of Iron and Steel Research International》2018年第6期658-665,共8页

摘　　要：The mechanical properties, thermodynamic features and their correlation were studied for La-Ce-Ni-Cu-Al high-entropy bulk metallic glasses （HE-BMGs）. Compressive testing indicated that the HE-BMGs are ductile on a microscopic scale but brittle on a macroscopic scale, because of the low fragility index rn of the HE-BMGs. In the non-isothermal process, the activation energies for glass transition for these HE-BMGs are the lowest of the known HE-BMGs. Large values of the Avrami exponent n imply that the crystallization process proceeded through three-dimensional growth and with an increasing nucleation rate. The activation energy for glass transition （Eg） is almost proportional to the HE-BMG fracture strength, because a higher Eg is required to dislodge the molecules from the glassy configuration for the HE-BMGs with a high strength. The findings provide unambiguous evidence for the correlation between the mechanical and thermodynamic properties.The mechanical properties, thermodynamic features and their correlation were studied for La-Ce-Ni-Cu-Al high-entropy bulk metallic glasses （HE-BMGs）. Compressive testing indicated that the HE-BMGs are ductile on a microscopic scale but brittle on a macroscopic scale, because of the low fragility index rn of the HE-BMGs. In the non-isothermal process, the activation energies for glass transition for these HE-BMGs are the lowest of the known HE-BMGs. Large values of the Avrami exponent n imply that the crystallization process proceeded through three-dimensional growth and with an increasing nucleation rate. The activation energy for glass transition （Eg） is almost proportional to the HE-BMG fracture strength, because a higher Eg is required to dislodge the molecules from the glassy configuration for the HE-BMGs with a high strength. The findings provide unambiguous evidence for the correlation between the mechanical and thermodynamic properties.

关 键 词：High-entropy bulk metallic glass Fracture mechanism Crystallization Avrami exponent Glass-transitionactivation energy 

分 类 号：O414.1[理学—理论物理] TG146.21[理学—物理]