非晶合金的结构非均匀性及其与弛豫行为间的关联研究

项目名称： 非晶合金的结构非均匀性及其与弛豫行为间的关联研究

项目编号： No.51501169

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 一般工业技术

项目作者： 柯海波

作者单位： 中国工程物理研究院

项目金额： 24万元

中文摘要： 非晶合金具有优异的物理、化学和力学性能，已引起了科学界和工业界的广泛研究和关注，然而其中的一些基础问题仍未能得到清晰的理解，如对非晶合金结构的构建表征以及弛豫行为的认知。因此，本项目拟采用典型金属非晶为模型合金，利用纳米压痕新技术和高分辨电镜对其结构非均匀性进行表征，同时借助于动态力学分析仪和差示扫描量热仪等手段对其弛豫行为进行系统研究。系统考察非晶合金体系中本征属性（脆度）引起的结构非均匀性差别和外界因素（热退火处理）导致的结构演化行为，分析脆度以及热退火处理对其弛豫行为的影响，并建立起结构非均匀性与弛豫行为之间的内在关联。同时，尝试揭示结构非均匀性和非指数弛豫的物理起源，为进一步认识玻璃转变现象和玻璃的本质提供理论依据和实验数据。

中文关键词： 非晶态合金；结构非均匀性；弛豫行为；脆度；热退火

英文摘要： Metallic glasses show some excellent physical, chemical and mechanical properties, which have attracted widespread attention from both scientists and industrialists. However, lots of basic problems in metallic glasses are still lack of clear understanding and remains challenges, such as the relaxation mechanism, the structure characterization and construction. In current work, serial metallic glasses are selected as model alloy systems. The structure heterogeneity will be characterized by nanoindentation technique and high resolving transmission electron microscopy (TEM). Meanwhile, the non-exponential relaxation behaviors will be investigated by means of dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC). The distinction of structure heterogeneity caused by the intrinsic property such as the fragility and the evolution of structure result from extrinsic factor such as the thermal annealing will be carefully studied. Furthermore, the impact of both the fragility as well as the thermal annealing upon the non-exponential relaxation will be considered. Based on these results, the correlation between structure heterogeneity and non-exponential relaxation behavior will be established. Finally, this study tries to reveal the underlying physical origin of structure heterogeneity and non-exponential relaxation behavior, which will provide both theoretic foundation and experimental data for the understanding of glass transition and the nature of glass.

英文关键词： amorphous alloy;structure heterogeneity;relaxation behavior;fragility;thermal annealing