Stability of periodic microstructure and property change of mesoscopic materials of phase-separation type alloys.

1.采用俄歇电子能谱、扫描电子显微镜和透射电子显微镜研究了在SiO_2衬底上制备的各种双层膜在退火过程中的微观结构变化。结果表明：(1)在Ag/Ge、Ag/Si、Al/Ge或Al/Si双层膜沉积状态下，薄膜内层为无定形的Ge或Si，外层为多晶的Ag或Al，退火后，Ge或Si原子析出，在自由表面扩散形成晶态的Ge或Si团簇。(2) Fe/Mo双层膜退火后形成了Fe-Mo平衡相图无法预测的FeMo金属间化合物。(3) Cu/Ge双层膜沉积状态下，内层为无定形Ge，外层为多晶Cu_3Ge。由于退火作用，内部的Ge层转变为多晶Cu_3Ge，部分Ge原子析出，在自由表面形成晶态的Ge团簇。提出了一种新的基于离散型扩散方程的相分解过程计算方法，并利用该方法对Fe-Mo二元合金体系的相分解过程进行了二维计算机模拟。研究了fe基合金中D0_3或B2粒子和ti基合金中Ti_3Al粒子等共格粒子的时效行为，结果表明，时效后期不仅晶粒粗化，而且硬度的降低也得到延缓。研究了氢和氘在Ti、α -Ti和Ti_3Al中的溶解和扩散。

1.Microstructure changes during annealing of various kinds of bilayr films on SiO_2 substrates were investigated by means of Auger electron spectroscopy, scanning electron microscopy and transmission electron microscopy. The results are as follows :(1) In the as-deposited state of Ag/Ge, Ag/Si, Al/Ge or Al/Si bilayr films, the inner layris amorphous Ge or Si and the outer layr is polycrystalline Ag or Al. Due to annealing, Ge or Si atoms come out and spread on the free surface forming crystalline Ge or Si clusters.(2) Annealing of Fe/Mo bilayr films brings the formation of FeMo intermetallic compound which is not predicted by the equilibrium phase diagram of Fe-Mo.(3) In the as-deposited state of Cu/Ge bilayr film, the inner layr is amorphous Ge and the outer layr is polycrystalline Cu_3Ge. Due to annealing, the inner Ge layr changes to polycrystalline Cu_3Ge and some Ge atoms come out and form crystalline Ge clusters on the free surface.2.A new calculation method for phase decomposition process based on discrete type diffusion equation was proposed, and two dimensional computer simulations were successfully performed for the phase decomposition in Fe-Mo binary alloy systems by utilizing the new method.3.Ageing behavior of coherent particles such as D0_3 or B2 particles in Fe-base alloys and Ti_3Al particles in Ti-base alloys was investigated and the results indicated that not only the particle coarsening but also the hardness decrease is retarded at the later stage of ageing.4.Dissolution and diffusion of hydrogen and deuterium in Ti, alpha-Ti or Ti_3Al were investigated.