Formation mechanism of self-organized nanostructured -metallic glass composite

（1）在快淬Cu-（Zr或Hf）-Ti合金中发现了纳米非晶复合材料的形成。（2）纳米晶颗粒具有直径为5至10 nm的细晶粒尺寸，并且均匀地分散在玻璃基质中。（3）纳米晶颗粒具有亚稳的立方结构，并具有富Cu成分，这为过冷液态下稳定的富Cu团簇的形成机制提供了理论依据。（4）两种合金体系的一次相变过程都很清楚，在Cu-Zr-Ti合金中，亚稳CuZr相的形成使纳米晶立方相保持在淬火态。但是，在Cu-Hf-Ti合金中，玻璃相和亚稳立方相转变为Cu 8Hf 3相。（5）在Cu-Zr-Ti合金中纳米结构-金属玻璃复合材料表现出高的机械强度，并且在初晶化状态下提高。这是由于两种不同的纳米晶相的形成。（6）在Zr_（65）Al_（7.5）Cu_（27.5）金属玻璃中，纳米准晶相的形成处于初始阶段，二十面体团簇在过冷液态下具有较高的稳定性。（7）研究了纳米准晶弥散Zr-Pt二元非晶合金的断裂机制。我们发现，断裂发生在分散的二十面体颗粒之间的玻璃区。(8)In通过这些研究，我们可以得出结论，基于金属玻璃的纳米级结构控制，利用稳定的簇和/或局部结构，对机械性能的改善是非常有效的，并且对于诸如材料中的形成机制和转变过程的基本性质的研究是非常重要的。

(1)The formation pf nanostructured-metallic glass composite has been found in the rapidly quendied Cu-(Zr or Hf)-Ti alloys.(2)The nanocrystalline particles have a fine grain size of 5 to 10 nm in diameter and are dispersed homogeneously in the glassy matrix.(3)The nanocrystalline particles have a metastable cubic structure with Cu-rich composition, which are brought us the formation mechanism of the stable Cu-rich clusters in the supercooled liquid state.(4)The primary transformation process is clarified in both the alloy systems, where another metastable CuZr phase is formed remaining the nanocrystalline cubic phase in the as-quenched state in the Cu-Zr-Ti alloy. However, the glassy and metastable cubic phases are transformed into the Cu8Hf3 phase in the Cu-Hf-Ti alloy.(5)The high mechanical strength is exhibited in the nanostructured-metallic glass composite in the Cu-Zr-Ti alloy and it is improved in the primary crystallized state. It is due to the formation of two different nanocrystalline phases.(6)Nano icosahedral quasicrystalline phase formation is found in the primary stage in the Zr65Al7.5Cu27.5 metallic glass, where the icosahedral cluster has a high stability in the supercooled liquid state.(7)The fracture mechanism of the nano icosahedral quasicrystal dispersed Zr-Pt binary amorphous alloy is investigated. We have found that the fracture takes place in the glassy region among the dispersed icosahedral particles.(8)In these studies, we can conclude that the nanoscale structure control based on the metallic glasses using the stable duster and/or local structure is very effective on the improvement of mechanical properties as well as is very important on the investigation of fundamental properties such as the formation mechanism and transformation process in the materials.