Enhanced plasticity of Fe-Nb-B-(Ni, Cu) bulk metallic glasses by controlling the heterogeneity and elastic constants

Influence of the micro-alloying of Cu and the partial substitution of Fe by Ni on mechanical properties was investigated in Fe-Nb-B-(Ni, Cu) bulk metallic glasses (BMGs). When the addition of Cu content was properly adjusted with 0.5 at.%, the (Fe0.71Nb0.06B0.23)(99.5)Cu-0.5 alloy exhibits enhanced plasticity of 4.5% due to the precipitation of nano-scale particles. Meanwhile, the partial replacement of Ni for Fe also effectively improves the plastic strain caused by tuning the elastic constants. The (Fe0.5Ni0.5)(71)Nb6B23 alloy with 1:1 Ni-to-Fe concentration ratio shows a large Poisson's ratio (0.356) and a pronounced plastic strain of 4.2%. These results indicate the improved room temperature plasticity of Fe-Nb-B-(Ni, Cu) BMGs can be achieved by the appropriate control of the heterogeneity and intrinsic elastic properties. (c) 2011 Elsevier B.V. All rights reserved.