The Microstructure of Zr-Based Bulk Metallic Glass and Glass Matrix Composite

Abstract

This study describes the microstructure of a Zr-based alloy (Zr 63.36 Cu 17.22 Ni 11.47 Al 7.95 , at.%) under different cooling conditions. The Zr-based alloy can obtain completely amorphous structure, amorphous/nanocrystalline droplet and amorphous/crystalline composite structure by fast to slow cooling rate. It is interesting in the amorphous/nanocrystalline droplet composite that the average compositions of the droplet phase and amorphous matrix phase were same as the original alloy composition and the contrasts of BEI (back scatting image) were different. The droplet phase formed with (Al,Ni) 2 Zr 3 , and Zr 2 Ni(Al,Cu) nanocrystalline structures based on the analysis of XRD (X-ray diffractometry), EBSD (electron backscatter diffraction) and TEM (transmission electron microscopy). And Zr 2 Ni(Al,Cu) nanocrystalline phase transfers to the Zr 2 Cu(Al,Ni) phase after thermal treatment. The equilibrium phases of the alloy have been identified as Zr 2 Ni phase, Zr 2 Cu phase, Al 2 NiZr 6 phase and τ3 (Zr 51 Cu 28 Al 21 , at.%) phase which reach four phases equilibrium at 1,073 K for one week.

Diffraction patterning using back scattering of electrons in Zr47.5Cu45.5Al5Co2 Bulk Metallic Glass Matrix Composites

“…These include observations under transmission electron microscopy [74], synchrotron light [75][76][77][78] and in-situ studies [14,74,79,80] but none have been made on the detailed use of more recent and advanced electron back scattered diffraction [81][82][83][84][85][86][87][88]. Few efforts have been made in this regard [32,44,65,[89][90][91][92][93], but none exist on its application on inoculated composites [22]. This is a new and unique technique which has been reported as complimentary to transmission electron microscopy [86,94].…”

Diffraction patterning using back scattering of electrons in Zr47.5Cu45.5Al5Co2 Bulk Metallic Glass Matrix Composites

“…These include observations under transmission electron microscopy [74], synchrotron light [75][76][77][78] and in-situ studies [14,74,79,80] but none have been made on the detailed use of more recent and advanced electron back scattered diffraction [81][82][83][84][85][86][87][88]. Few efforts have been made in this regard [32,44,65,[89][90][91][92][93], but none exist on its application on inoculated composites [22]. This is a new and unique technique which has been reported as complimentary to transmission electron microscopy [86,94].…”