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The intrinsic nature of bulk metallic glasses Zr 60+ x Al 8 Ni 15− x Cu 17 ( x = 0–5 at.%) can be effectively modified by changing the Zr/Ni ratio from 60/15 to 65/10. The crystallization behaviors upon isothermal annealing are also changed from multi-step crystallization to single step crystallization with the variation of the Zr/Ni ratio. Ductility improvement attributed to the retarded crystallization kinetics was proposed based upon the results of indentation experiment and crystallization kinetic analysis.

Fe-base bulk metallic glasses in the alloy system Fe–C–Si–B–P–Cr–Mo–Al have been developed using hot metal and industrial ferro-alloys. The amorphous alloys can be cast into fully amorphous rods with diameters of up to 4 mm, demonstrating high glass-forming ability and high strength (>3 GPa). Thermal stability and crystallization behavior of the Fe–C–Si–B–P–Cr–Mo–Al bulk metallic glasses are also investigated. The Fe-base bulk metallic glasses can be produced cost-effectively and massively for extensive structural applications.

The icosahedral phase formation and associated structural evolutions in the Al–Cu–Fe ternary system have been examined through the repeated cold rolling and folding (R&F) process of elemental foils with a target composition of Al 62.5 Cu 25 Fe 12.5 (at.%). Upon early increments of the rolling and folding cycles, the elemental Fe foil was dispersed through the refined Al and Cu layers. When the rolling and folding step reached 40 cycles the Al 2 Cu phase has been observed, however, no ternary phases were identified even upon additional R&F cycles. The stable icosahedral phase (i-phase) could be obtained after isothermal annealing of the R&F processed specimens at 650 and 750 °C. The phase evolution during repeated cold R&F process of the Al–Cu–Fe system and upon heat-treatments are discussed in terms of the formation and dissolution of the Al 2 Cu and Al 7 Cu 2 Fe phases.

Bulk metallic glasses have a frozen-liquid structure comprising multi-component elements. Plastic deformation of bulk metallic glasses is highly localized into shear bands. As the shear band propagates, excess free volume is generated and spontaneously coalesced, leading to the formation of nanometer-scale voids. The voids evolve to be cracks that immediately cross the whole sample area causing a catastrophic fracture even under compression. Therefore, to prohibit the catastrophic failure, atomic clustering kinetics should be retarded. Here, we report a new monolithic zirconium-base metallic glass that is highly deformable without global failure under compression. Due to high thermal activation energy for the atomic movement, the crack formation attributed to void coalescence within shear bands can be prevented exhibiting extraordinarily high ductility under compression.