题  目: Glass-forming ability, microstructure and mechanical properties of Cu-Zr-Al bulk metallic glass with addition of Co

报告人: 周巍

时  间:  2012年 11月24日 09:00 开始

地  点：B314

摘  要:

Investigations were carried out to examine the effect of Co addition on the glass-forming ability (GFA), microstructure and mechanical properties of Cu₄₆Zr₄₆Al₈ bulk metallic glasses. It is found that the GFA of (Cu₄₆Zr₄₆Al₈)_100-xCo_x (x=0, 1, 2, 3, and 4 at%) reduces with the increasing of Co content, and correlates well with the parameters, such as the supercooled liquid region width DT_x, the reduced glass transition temperature T_rg and γ. The plasticity and the fracture strength are however found to be enhanced with the Co addition. Notably with an appropriate amount of Co addition, naonoscale phase separation with the formation of Cu-rich and Co-rich glassy phases takes place during solidification, which improves the mechanical properties of the alloys effectively.

     TEM bright-field images, SAED patterns, and the corresponding HRTEM images for

     the Cu₄₆Zr₄₆Al₈ (a, b), (Cu₄₆Zr₄₆Al₈)₉₈Co₂ (c, d), and (Cu₄₆Zr₄₆Al₈)₉₆Co₄ (e, f) rods.