Bulk metallic glasses (BMG) exhibit high strength but limited ductility due to their inhomogeneous deformation behavior under load, which seriously limits their application. To prevent the inhomogeneous deformation, attempts have been made by introducing in situ formed ductile dendritic phases in present study. Ti-base BMG-forming alloys were selected and modified by adding refractory metals Nb, Ta, Mo and Zr. Ductile dendrites / nanostructured matrix composites were synthesized which exhibit a plastic strain larger than 14% together with high strength (ultimate strength higher than 2400 MPa). The experimental results show evidence that shear banding is the main deformation mode in nanostructured matrix. The localized shear bands are limited in the inter-dendrite regions by micrometer-sized dendrites. The dendrites act as obstacles to limit the excessive deformation in the localized shear bands and contribute to the plasticity by dislocations.
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