CAJ | 학술논문

通过系统的透射电子显微镜观察，在回火的Zr-Al-Ni-Cu-Ag块体金属玻璃中发现了准晶相和纳米准晶相。具有五次对称性，三次对称性及二次对称性的选区电子衍射谱及微束电子衍射谱证明初始晶化过程中析出的相为二十面体准晶。定量观察表明高的形核率是纳米准晶形成的原因。添加银有助于纳米准晶的形成。二十面体准晶相在初始晶化过程中的析出暗示着块体金属玻璃和二十面体结构之间存在着本征的相关性。
통과계통적투사전자현미경관찰，재회화적Zr-Al-Ni-Cu-Ag괴체금속파리중발현료준정상화납미준정상。구유오차대칭성，삼차대칭성급이차대칭성적선구전자연사보급미속전자연사보증명초시정화과정중석출적상위이십면체준정。정량관찰표명고적형핵솔시납미준정형성적원인。첨가은유조우납미준정적형성。이십면체준정상재초시정화과정중적석출암시착괴체금속파리화이십면체결구지간존재착본정적상관성。
Quasicrystals and nano-quasicrystals were discovered in annealed Zr-Al-Ni-Cu-Ag bulk metallic glasses by systematic transmission electron microscopic (TEM) analysis. Selected area electron diffraction (SAED) and micro-beam diffraction patterns corresponding to five-, three-, and two-fold rotational symmetry were obtained. It demonstrates that the precipitated phases in the primarily devitrified bulk metallic glasses are icosahedral quasicrystalline phases. The formation of nano-quasicrystals is attributed to the high nucleation density and nucleation rate. Moreover, the addition of Ag benefits the formation of the nano-quasicrystalline phase. The discovery of icosahedral phases directly reflects an intrinsic relationship between the bulk metallic glasses and the icosahedral structure.