OBSERVATION OF THE COMPLEX LOCAL CRYSTALLIZATION PROCESS IN Ti-Zr-Cu-Pd AMORPHOUS RIBBONS AND BULK METALLIC GLASS

In recent years, bulk metallic glasses (BMGs) have attracted much attention, especially concerning the reasons for the high glass-forming ability. To understand properties and glass-forming ability of BMGs, it is important to investigate their atomic structure in details. The structure of the metallic glass, derived from diffraction studies, confines mainly to short-range-order atomic correlations, which are statistically averaged over the glassy specimens. In the present study, local structure of a BMG and ribbons was observed using a high-resolution TEM (TECNAI G(2) FEG). The TEM images of the BMG before annealed in the temperature below the crystallization clearly reveal a duplex microstructure consisting of nanocrystalline particles about 5-10 nm in size distributed uniformly in the amorphous matrix. Due to the FFT research the crystalline phases may be indexed as the Cu8Zr3, Cu3Pd, CuTi2 and CuTiZr.