Phase separation in bulk-type metallic glass and effect of cooling rate on the phase-separated microstructure have been investigated in Zr 35Gd 20Al 25-xNi 20+x (x = 0, 2, 4, 8) alloys. Among the alloys investigated, molten Zr 35Gd 20Al 23Ni 22 undergoes metastable liquid phase separation in the undercooled regime and subsequently solidifies into two different Zr-rich and Gd-rich amorphous phases, which exhibit enough GFA enabling formation of 1 mm diameter phase-separating glass. The liquid melt undergoes phase separation by spinodal decomposition when the degree of undercooling is relatively large, while by nucleation and growth mechanism when the degree of undercooling is relatively low. The lower degree of undercooling results in the composition more close to the terminal composition expected from the miscibility gap.
Bibliographical noteFunding Information:
This work was supported by the Global Research Laboratory Program of the Korea Ministry of Education, Science and Technology. S.W. Sohn acknowledge the support from the Second Stage of Brain Korea 21 Project in 2011. Stimulating discussions with J.H. Han, N. Mattern, O. Shuleshova, J. M. Park and J. Eckert are gratefully acknowledged.
All Science Journal Classification (ASJC) codes
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry