Determination of accurate theoretical values for thermodynamic properties in bulk metallic glasses  

作　　者：Pei-You Li Gang Wang Ding Ding Jun Shen 

机构地区：[1]School of Materials Science and Engineering,Harbin Institute of Technology [2]Laboratory for Microstructures,Shanghai University

出　　处：《Advances in Manufacturing》2013年第4期293-304,共12页先进制造进展（英文版）

基　　金：supported by the grant from the National Natural Science Foundation of China(Grant No.51025415)

摘　　要：Deviation values of specific heat difference ACp, the Gibbs free energy difference AG, enthalpy dif- ference AH, and entropy difference AS between the supercooled liquid and corresponding crystalline phase produced by the linear, hyperbolic, and Dubey＇s expres- sions of ACp and the corresponding experimental values are determined for sixteen bulk metallic glasses （BMGs） from the glass transition temperature Tg to the melting temperature Tm. The calculated values produced by the hyperbolic expression for ACp most closely approximate experimental values, indicating that the hyperbolic ACp expression can be considered universally applicable, compared to linear and Dubey＇s expressions for ACp, which are accurate only within a limited range of condi- tions. For instance, Dubey＇s ACp expression provides a good approximation of actual experimental values within certain conditions （i.e., ~ = ACg/AC~ 〈 2, where ACpg and ACp represent the specific heat difference at temperatures Tg and Tm, respectively）.Deviation values of specific heat difference ACp, the Gibbs free energy difference AG, enthalpy dif- ference AH, and entropy difference AS between the supercooled liquid and corresponding crystalline phase produced by the linear, hyperbolic, and Dubey＇s expres- sions of ACp and the corresponding experimental values are determined for sixteen bulk metallic glasses （BMGs） from the glass transition temperature Tg to the melting temperature Tm. The calculated values produced by the hyperbolic expression for ACp most closely approximate experimental values, indicating that the hyperbolic ACp expression can be considered universally applicable, compared to linear and Dubey＇s expressions for ACp, which are accurate only within a limited range of condi- tions. For instance, Dubey＇s ACp expression provides a good approximation of actual experimental values within certain conditions （i.e., ~ = ACg/AC~ 〈 2, where ACpg and ACp represent the specific heat difference at temperatures Tg and Tm, respectively）.

关 键 词：Bulk metallic glass （BMG） ~ Specificheat ~ Linear expression ~ Hyperbolic expression 

分 类 号：O614.813[理学—无机化学]