Heterogeneous nucleation of β-type precipitates on nanoscale Zr-rich particles in a Mg-6Zn-0.5Cu-0.6Zr alloy.
Zirconium (Zr) is an important alloying element to Mg-Zn-based alloy system. In this paper, we report the formation of the β-type precipitates on the nanoscale Zr-rich particles in a Mg-6Zn-0.5Cu-0.6Zr alloy during ageing at 180°C. Scanning transmission electron microscopy examinations revealed that the nanoscale Zr-rich [0001]α rods/laths are dominant in the Zr-rich core regions of the as-quenched sample after a solution treatment at 430°C. More significantly, these Zr-rich particles served as favourable sites for heterogeneous nucleation of the Zn-rich β-type phase during subsequent isothermal ageing at 180°C. This research provides a potential route to engineer precipitate microstructure for better strengthening effect in the Zr-containing Mg alloys.
Australian Centre for Microscopy and Microanalysis, The University of Sydney, New South Wales, 2006, Australia. cuilanwu2010@gmail.com.
Hongmei
H
Zhu
Gang
G
Sha
Jiangwen
J
Liu
Hongwei
H
Liu
Cuilan
C
Wu
Chengping
C
Luo
Zongwen
Z
Liu
Rongkun
R
Zheng
Simon P
SP
Ringer