非晶态金属的结构与合金的玻璃形成能力

STRUCTURE AND GLASS FORMING ABILITY (GFA) OF AMORPHOUS ALLOYS

本文提出了一种非晶态金属的微观结构模型—Cluster模型,根据此模型的统计热力学计算导出了一个表征合金玻璃形成能力(GFA)的参量: α_c=[1-2.08/Φ_m]T_g/T_m其中T_g为玻璃转变温度,T_m为熔点,Φ_m为合金的熔化熵,α_c值越大合金越易形成非晶态。这个新的合金GFA判据不但为过去的几种GFA经验判据提供了理论依据,而且比它们更合理。

A new microstructure model is developed for amorphous alloys, so called Clus-ter model, in which the amorphous phase is thought of composing of randomly distributed or-dered clusters of different sizes. Thermodynamic calculation on this model deduces a parameter describing the glass forming ability of metallic alloys: a_c=(1-2.08/φm)T_g/ T_m, where T_g is glass transition temperature, T_m is the melting temperature, and φm is entralpy change of melt-ing. It is believed that easy glass forming alloy systems have larger values of a_c This new criter- ion of GFA not only provides the theoretical background for several GFA criteria in the litera-ture cited, but also can predict the GFA of many alloy systems more reasonably and accurately.