Formation and mechanical behavior of (Fe0.5Ni0.5)80−xMoxB20 (x = 0–8) amorphous alloys

Abstract

Glass forming ability, thermal stability and mechanical behavior of (Fe0.5Ni0.5)80−xMoxB20 (x=0, 2, 4, 6, 8) amorphous alloys were studied by XRD, TEM, SEM, DSC, tensile test, microhardness test and tearing test. The effects of Mo addition on glass formation, strength and ductility of (Fe0.5Ni0.5)80−xMoxB20 amorphous alloys were discussed. The substitution of Mo for Fe and Ni simultaneously causes improvement in glass forming ability and thermal stability, and changes the crystallization process. The tensile fracture strength of amorphous alloy depends on both hardness and ductility; the alloy with high hardness and good ductility simultaneously also has a high tensile fracture strength. The (Fe0.5Ni0.5)78Mo2B20 amorphous alloy exhibits good glass forming ability and the highest tensile fracture strength among (Fe0.5Ni0.5)80−xMoxB20 alloys. Micro-plastic deformation occurred in ductile and brittle amorphous alloys that both show viscous flow characteristics. The mechanical behavior of (Fe0.5Ni0.5)80−xMoxB20 amorphous alloys is related to the average outer shell electron concentration of metal atoms.