强脆概念在Al85Ni10Ce5金属玻璃液体上的应用.docVIP

 Application of strong-fragile concept to Al85Ni10Ce5 metallic glass-forming liquid# ZHOU Chao, HU LiNa, BIAN XiuFang** 5 10 15 20 25 30 35 40 (Key Laboratory of Liquid Structure and Heredity of Materials(Ministry of Education), Shandong University, JiNan 250061) Abstract: The question concerning the fragility of the so-called “marginal” glass forming metallic alloys is obligatory and interesting. Based on the proposition that both the rates of glass transition and that of crystallization in metallic glasses scale as the viscosity, the fragility parameter, m, for Al85Ne10Ce5 glass has been evaluated by means of thermal measurements from the glass transition to the close crystallization temperature. The calculated value of fragility parameter “m” shows that the investigated Al85Ni10Ce5 glasses exhibit a characteristic of being extremely fragile. It renders supports to the controversial relationship between glass-forming ability and fragility, for which they are expected to be parallel. Keywords: amorphous alloy; glass-forming ability; fragility; Al85Ni10Ce5 0 Introduction The classification of glasses as strong or fragile introduced by Angell [1-3] is perhaps the most far-reaching concept since it gives new insights for glass transition, structural relaxation phenomenon, glass or supercooled liquid structure and so on. During the past few years, the investigation on the fragility parameter, m, was mainly focused on simple and complex covalent molecular liquids, polymers, ionic melts, oxides and alcohols [4-6]. According to the reported fragility parameters, it is believed that, for strong and fragile liquids, the limit of fragility parameters is about 16 and 200, separately. An initial attempt to investigate the values of m for glass-forming metallic alloys was conducted by Komatsu in 1995 [7]. Then in order to obtain more reliable estimates of the fragility parameter for metallic glasses, Perera et.al [8] calculated the values of m for bulk metallic glasses (B