Phase competition mediated by composition and pressure in Zr2Cu1−xNix system

• Phase competition between C11b, C16 and E93 phases in Zr2Cu1−xNix is studied.
• The E93 phase is less competitive than the C11b and C16 ones.
• External pressure as well as increasing Ni content stabilizes the C16 phase.
• Some phenomena in crystallization of related BMGs find rationalization.
• Design of BMG composites with tunable precipitates is proposed accordingly.

Phase competition between C11b, C16 and E93 phases under pressure (0–60 GPa) in Zr2Cu1−xNix (x = 0, 0.125, 0.25, 0.50, 0.75, 0.875 and 1) alloys has been investigated by first-principles pseudopotential calculations. The whole picture of phase competition mediated by both external pressure and composition has been unambiguously established by modeling using both supercell (SC) method and virtual crystal approximation (VCA) method, which sheds light on the pressure dependent glass stability and crystallization behavior of related alloy systems. It is revealed that both pressure and increasing Ni content stabilize the C16 phase over the other two. The underlying mechanism of external pressure and composition stabilizing the C16 phase is also analyzed. A feasible procedure for achieving metallic glass composites with tunable precipitated phases is proposed.