Hu Lina, Bian Xiufang, Qin Xubo, Yue Yuanzheng, Zhao Yan, Wang Caidong
Key laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University (South Part), Jingshi Road 73, Jinan 250061, People's Republic of China.
J Phys Chem B. 2006 Nov 2;110(43):21950-7. doi: 10.1021/jp063628q.
Due to the inaccessibility of the supercooled region of marginal metallic glasses (MMGs) within the experimental time window, we study the cluster kinetics above the liquidus temperature, Tl, to acquire information on the fragility of the MMG systems. The thermodynamic basis for the stability of locally ordered structure in the MMG liquids is discussed in terms of the two-order-parameter model. It is found that the Arrhenius activation energy of clusters, Deltah, is proportional to the chemical mixing enthalpy of alloys, DeltaH(chem). Fragility of the MMG forming liquids can be described by the ratio of the absolute DeltaH(chem) value to the glass transition temperature, Tg. The manner of vitrification during rapid solidification is an important factor for the discrepancy between the data presented in this paper and the prediction of the two-order-parameter model concerning the relation between Delta h and the liquid fragility.
由于在实验时间窗口内无法获取边际金属玻璃（MMG）的过冷区域，我们研究了液相线温度Tl以上的团簇动力学，以获取有关MMG系统脆性的信息。根据双序参量模型讨论了MMG液体中局部有序结构稳定性的热力学基础。发现团簇的阿仑尼乌斯活化能Δh与合金的化学混合焓ΔH(chem)成正比。形成MMG的液体的脆性可以用绝对ΔH(chem)值与玻璃化转变温度Tg的比值来描述。快速凝固过程中的玻璃化方式是本文所呈现的数据与双序参量模型关于Δh与液体脆性之间关系的预测存在差异的一个重要因素。
