摘要
用TEM研究了Ni_(67)Zr_(33)非晶合金晶化过程中亚稳相与稳定相之间存在的过渡区。在点阵像上亚稳相为宽的或宽窄相间的条纹,而稳定相为单一的窄条纹。过渡区中宽窄条纹的分布是随机的,看不出明显的规律。其电子衍射圈也没有平移对称性,可以看成亚稳态与稳定态的衍射谱之间的变化过程。 以相同原子面不同堆垛间距的模型模拟了过渡区衍射强度的分布,与实际强度符合得很好。
A transition area, which appears in the transformation from a metastable phase to a stable one during the crystallization of Ni-33at% Zr amorphous alloy, had been investigated by means of TEM. From the lattice image, it can be seen that the unstable phase corresponds to fringes with broad spacing or alternate between broad and narrow spacings, the stable phase corresponds to a single kind of fringes with narrow spacing, but for the transition area the arrangement of fringes with broad or narrow spacing is random and shows no regularity. In addition, for this area, the electron diffraction pattern exhibits no translation summetry. The pattern can be seen as one of the transformation process between the unstable phase and the stable one. Distributions of the diffraction intensities of the transition area are simulated by means of models with identical atomic planes but various packing spacings, the result agrees with the actual intensity distribution very well.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
1989年第12期2034-2038,共5页
Acta Physica Sinica
