Thermodynamics and Kinetics of Metastable Alloy Formation

研究了机械合金化、离子辐照和气相沉积形成的合金中亚稳态合金形成的热力学和动力学。进行了考虑过冷液体过量比热的热焓和自由能计算。用X射线衍射仪、电子显微镜和卢瑟福背散射法研究了应力和结构弛豫对薄膜扩散偶相平衡和反应动力学的影响。采用电子辐照亚稳非晶合金的方法研究了非晶态合金的扩散机制和点缺陷过饱和度对相平衡的影响。这项研究有望促进我们对亚稳态合金相形成的热力学和动力学方面的理解。这些不同寻常的材料可以大量生产，并具有商业可能性。

The thermodynamics and kinetics of metastable alloy formation are investigated in alloys formed by mechanical alloying, ion irradiation, and vapor deposition. Enthalpy and free energy calculations are performed that account for excess specific heat of an undercooled liquid. Effects of stress and structural relaxation on phase equilibria and reaction kinetics in thin film diffusion couples are studied by X-ray diffraction, electron microscopy, and Rutherford backscattering spectrometry. Electron irradiation of amorphous alloys in metastable equilibrium with terminal solution precipitates is employed to examine diffusion mechanisms in amorphous alloys and the effects of point defect supersaturation on phase equilibria. %%% This research is expected to advance our understanding of both the thermodynamic and kinetic aspects of metastable alloy phase formation. These unusual materials can be made in large quantities and have commercial possibilities.