Synthesis and characterization of copper fiber reinforced Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 bulk metallic glass

Highly conductive Cu fibers were introduced into Zr41.2Ti13.8Cu12.5Ni10Be22.5 (Vitreloy 1) Bulk Metallic Glass (BMG) of poor conductivity to produce a composite with a thermal anisotropy. The composites with circular and square cross-sections with the volume fraction ranging from 7 to 60% were processed successfully by pressure-gravity infiltration. Differential Scanning Calorimetry (DSC) showed that the BMG matrix remained predominantly amorphous after adding up to 60 vol.% of Cu fibers. The limited crystallization at the Cu/Vitreloy 1 interface was observed under optical microscope. This crystallization is attributed to heterogeneous nucleation starting from the Cu/Vitreloy 1 interface followed by the growth in the region with higher Cu concentration around the copper fibers. A combination of two-dimensional triangular and square ordering of the fibers was observed in the composite samples. X-ray diffraction patterns of the composites showed the peaks from the reinforced fibers and crystals around the Cu/Vitreloy 1 interface superimposed on the broad diffuse maxima from the amorphous phase. Best processing parameters in terms of processing time and temperature were determined for the composite reinforced with 60 vol.% fibers. (C) 2006 Elsevier B.V. All rights reserved.