Plasticity Of Bulk Metallic Glasses Research Articles

A development of Ni-based alloys with enhanced plasticity

Enhancement of plasticity in Ni-based injection cast bulk metallic glasses (BMGs) and metallic glass matrix composites (MGMCs) has been investigated. The injection-cast Ni 59Zr 16Ti 13Si 3Sn 2Nb 7 BMG showed a significantly improved plastic region to failure of 6.5%, as compared to that of the injection-cast Ni 59Zr 20Ti 16Si 2Sn 3 BMG of 2%. The Ni 59Zr 20Ti 16Si 2Sn 3 MGMC containing brass-fibers shows macroscopic plasticity after yielding, and the level of plastic strain increased to around 2% with increasing brass content up to 40 vol.%, while monolithic warm-extruded Ni 59Zr 20Ti 16Si 2Sn 3 BMG show no plastic deformation region. Present study shows that the plasticity of BMG can be improved by selecting proper BMG alloy composition or by introducing ductile reinforcing phase in the BMG matrix.

A development of Ni-based alloys with enhanced plasticity

Enhancement of plasticity in Ni-based injection cast bulk metallic glasses (BMGs) and metallic glass matrix composites (MGMCs) has been investigated. The injection-cast Ni59Zr16Ti13Si3Sn2Nb7 BMG showed a significantly improved plastic region to failure of 6.5%, as compared to that of the injection-cast Ni59Zr20Ti16Si2Sn3 BMG of 2%. The Ni59Zr20Ti16Si2Sn3 MGMC containing brass-fibers shows macroscopic plasticity after yielding, and the level of plastic strain increased to around 2% with increasing brass content up to 40 vol.%, while monolithic warm-extruded Ni59Zr20Ti16Si2Sn3 BMG show no plastic deformation region. Present study shows that the plasticity of BMG can be improved by selecting proper BMG alloy composition or by introducing ductile reinforcing phase in the BMG matrix.

Crack-tip plasticity in bulk metallic glasses

The fracture and plastic deformation mechanisms of a Zr–Ti–Ni–Cu–Be bulk metallic glass are reviewed. In particular, the effects of stress state and local heating on the development of shear bands are discussed. The temperature increase at the crack tip during fracture was measured and was found to be consistent with predictions of the dissipation of plastic work as heat. In order to examine the effect of stress state on failure, tensile bars with notches of varying severity were used to superimpose a tensile mean stress. A constant mean stress was found to provide an accurate correlation with the onset of strain localization and failure.

Enhanced Plasticity of Bulk Metallic Glasses Containing Ductile Phase Dendrite Dispersions

Enhanced Plasticity of Bulk Metallic Glasses Containing Ductile Phase Dendrite Dispersions

Enhanced Plasticity of Bulk Metallic Glasses Containing Ductile Phase Dendrite Dispersions

Enhanced Plasticity of Bulk Metallic Glasses Containing Ductile Phase Dendrite Dispersions

Microstructure controlled shear band pattern formation and enhanced plasticity of bulk metallic glasses containing in situ formed ductile phase dendrite dispersions

Results are presented for a ductile metal reinforced bulk metallic glass matrix composite based on glass forming compositions in the Zr-Ti-Cu-Ni-Be system. Primary dendrite growth and solute partitioning in the molten state yields a microstructure consisting of a ductile crystalline Ti-Zr-Nb beta phase, with bcc structure, in a Zr-Ti-Nb-Cu-Ni-Be bulk metallic glass matrix. Under unconstrained mechanical loading organized shear band patterns develop throughout the sample. This results in a dramatic increase in the plastic strain to failure, impact resistance, and toughness of the metallic glass.