一种预测非晶合金的非晶形成能力新判据

A New Criterion for Predicting Glass Forming Ability of Metallic Glasses

本文提出了一种非晶合金的非晶形成能力(GFA)新判据β’,表达式为(Tg/Tx-Tg/Tl/η),其中Tg,Tx,Tl和η分别为合金的玻璃转变温度、起始晶化温度、液相线温度和常系数。新判据β’的理论基础是非晶形成能力的本质涵义,即GFA不仅表征合金熔体形成非晶的能力,也表征非晶合金在受热条件下的稳定性。采用文献报道的大量数据,对新判据和现有判据的预测能力进行了比较。结果表明,跟其他现有判据相比,新提出的β’判据与临界冷速具有最高的线性相关系数,能更好地预测出合金的非晶形成能力。

According to the meaning of glass-forming ability（GFA）,the GFA should incorporate both the factors of glass-forming tendency and the thermal stability of bulk metallic glasses.A modified criterion,β＇,defined as Tg/Tx-Tg/Tl/η（Tg,Tx,Tl and η denote the glass transition temperature,the onset of crystallization temperature,the liquidus temperature and constant coefficient,respectively）,has been proposed for assessing the glass-forming ability（GFA） of bulk metallic glasses（BMGs）.A survey of the readily available experimental data associated with the thermal analysis of various BMG alloys demonstrates that the new β＇ criterion exhibits much better correlation with the critical cooling rate than other currently used criteria,and thus could reflect the GFA more precisely.