Structure and mechanical strength of Al-V-Fe melt-spun ribbons containing high volume fraction of nanoscale amorphous particles

A new nonequilibrium structure consisting of nanoscale amorphous particles surrounded by fcc-Al phase was found to form in an Al94V4Fe2 alloy rapidly solidified at the condition of circumferential velocity of 40 mis and ejection temperature of molten alloy between 1273 and 1423 K. Deviations of the alloy component and solidification condition cause the formation of the nanoscale mixed structure of Al+icosahedral(I) phases or Al+I+amorphous phases. The sizes of the amorphous and Al phase regions are about 10 and 7 nm, respectively, and the volume fraction of the amorphous place region is about 60%. The formation of the nanoscale amorphous particles in coexistence with Al phase is presumably due to the suppression of the transition from super-cooled liquid to I-phase resulting from the retardation of the diffusivity of the solute elements. The tensile strength is as high as 1400 MPa for the mixed amorphous+Al phases and decreases significantly by the transition to I+Al phases. The first success in fabricating a nano-amorphous structure is particularly important for the subsequent development of nanophase materials.