Quinary Zr-Al-Ni-Cu-(Ag or Pd) amorphous alloys exhibit a double-stage devi
trification on heating. Primary devitrification leads to the precipitation
of nanoscale icosahedral particles with a size from 20 to 50 nm. High nucle
ation and low growth rates are obtained in a polymorphous mode for the Ag-c
ontaining alloys and a diffusion-controlled mode for the Pd-containing allo
ys. The nanoscale mixed structure alloys exhibit improved strength and duct
ility as compared to the corresponding amorphous single-phase alloys.