Crystallization products of amorphous Zr–Cu–Ni alloy

The final crystallization products of the amorphous Zr70Cu20Ni10 alloy were identified by employing the differential scanning calorimetry (DSC), X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). It is noted that there still exists a face-centered cubic Zr2Ni (f.c.c.-Zr2Ni) phase during crystallization of the amorphous Zr70Cu20Ni10 alloy upon heating up to 600°C in spite of the metastable characteristics of the f.c.c.-Zr2Ni phase thermodynamically. On the basis of the experimental results, it is deduced that the final crystallization products of the amorphous Zr70Cu20Ni10 alloy consist mainly of the b.c.t.-Zr2Cu and f.c.c.-Zr2Ni phases. As for the distribution of these two crystalline phases, the primary b.c.t.-Zr2Cu particles with a larger grain size are precipitated from the amorphous matrix first, occupying the main part of the amorphous matrix. The nanoscale f.c.c.-Zr2Ni particles with an average grain size of about 20–30 nm are formed among the b.c.t.-Zr2Cu particles. HRTEM observation also confirms that there exist two different areas, which correspond to the (213) plane of the b.c.t.-Zr2Cu phase and (531) plane of the f.c.c.-Zr2Ni phase, respectively.