Ultrahigh Tensile Strengths of Al88Y2Ni9M1 (M = Mn or Fe) Amorphous Alloys Containing Finely Dispersed fcc-Al Particles

Abstract

Al-based amorphous alloys containing finely dispersed fcc-Al particles were found to exhibit tensile strengths and hardness higher than those of amorphous single phase alloys with same compositions, in addition to good bending ductility. The Al88Y2Ni9Fe1 amorphous alloy containing 7% volume fraction (σf) of the fcc-Al particles with a size of about 3-4 nm has a high tensile fracture strength (σf) of 1320 MPa and a specific strength (σf/density=σs) of 40 x 103 m. Similarly, the mixed Al88Y2Ni9Mn1 alloy with Vf of 24% has 1260 MPa for σf and 38 × 103 m for σs. It is notable that the σf and σs values for the former alloy are higher than the highest values (1140 MPa and 38 × 103 m) of Al-based amorphous alloys. The high strengths combined with good bending ductility are presumably due to a dispersion hardening of the fee supersaturated solution which has the hardness higher than that of the amorphous phase with the same composition. © 1990, The Japan Institute of Metals. All rights reserved.