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迄今为止,已经研究了大约90个二元金属系统的多层膜离子束混合,获得了许多非晶态合金(金属玻璃)。离子束混合不仅能在负生成热的,通常认为是易玻璃化的系统中合成金属玻璃,而且在正生成热的非玻璃系统,甚至在正生成热很大的互不固溶系统中也合成了金属玻璃。对此,用Miedema的生成热模型构造了二元金属系统的自由能图。在考虑了多层膜中的界面自由能后,提出了一个统一的热力学模型。对正生成热的系统,界面自由能使多层膜提高到比非晶相高的能态,从而有可能形成玻璃。而界面能对于负生成热提供的非晶化驱动力的影响可以忽略。另外,离子束混合也获得了五种结构类型的亚稳晶相(MX)。并从实验观察到的MX相和母相之间晶体学关系推导出MX相形成的原运动机制。自由能图包括了计算的MX相的自由能曲线后就更为完整了,可以用来预言离子束混合中有关合金相的形成。作者提出了用稳态退火实验来校验计算的自由能图在一些重要成份点的相对能态的合理性。实验表明,合金相的演化次序与计算推演的结果符合得很好,从而证实了Miedema理论的适用性。界面的概念也适用于同样开始于多层膜的固态反应技术。在一些正生成热的系统中,通过适当设计使多层膜中包含足够份额的界面,稳态退火确实获得了新的金属玻璃?
Hitherto, multilayer film ion beam mixing of about 90 binary metal systems has been studied to obtain many amorphous alloys (metallic glasses). Ion beam mixing not only synthesizes metallic glass in systems that are negatively-heated, and are generally considered to be vitrifiable, but also in non-glass systems that are generating heat, even in systems that are largely heat-generating Metallic glass. In this regard, we use Miedema’s generated thermal model to construct the free energy diagram of the binary metal system. After considering the interfacial free energy in multilayers, a unified thermodynamic model is proposed. For systems that are generating heat, the free interface allows the multilayer film to be raised to a higher energy state than the amorphous phase, making it possible to form glass. The influence of the interface on the amorphization driving force provided by the negative heat of formation can be neglected. In addition, ion beam mixing also obtained five structural types of metastable phase (MX). From the experimental observation of the relationship between the MX phase and the mother phase of the relationship between the deduced MX phase formation of the original motion mechanism. The free energy map, which includes the calculated free energy curve of the MX phase, is more complete and can be used to predict the formation of the alloy phase in ion beam mixing. The authors propose the use of steady state annealing experiments to verify the rationality of the relative energy states of the calculated free energy diagrams at some important component points. Experiments show that the order of evolution of the alloy phase is in good agreement with the result of calculation and deduction, which proves the applicability of Miedema theory. The concept of interface also applies to solid-state reaction techniques that also begin with multilayer films. In some systems that are generating heat, steady-state annealing does indeed result in a new metallic glass by proper design to include a sufficient proportion of the interface in the multilayer?