Interfacial characteristics and mechanical properties of a modified Nb-containing Zr-based bulk metallic glass composite reinforced with W fiber

Tungsten (W) fiber reinforced Zr₄₇Ti₁₃ Cu₁₁Ni₁₀Be₁₆Nb₃ bulk metallic glass composite has been prepared by melt infiltration casting. Interfacial characteristics of the composite were analyzed by sessile drop technique, x-ray diffraction (XRD), scanning electron microscopy (SEM), electron probe x-ray microanalysis (EPMA), and nanoindenter. Results indicate that Zr₄₇Ti₁₃Cu₁₁ Ni₁₀Be₁₆Nb₃ melt wets the W substrate, and the interfacial bond composed of a diffusion-dissolution layer between Zr₄₇Ti₁₃Cu₁₁Ni₁₀ Be₁₆Nb₃ matrix and W fiber is in good condition. Due to these excellent interfacial characteristics, the mechanical properties of the composite are considerably enhanced with increasing volume fraction of W fiber. It was found that the compressive strength of 70% volume fraction of W fiber composite is 2.6 GPa, which is 58% higher than the value exhibited by the unreinforced matrix. At the same time, the reinforced matrix exhibits 13% plastic deformation when tested under quasi-static compression conditions. Instead of shear mode seen for the unreinforced matrix, the failure mode of the 70% volume fraction W fiber composite is mainly caused by fiber splitting and buckling. Also, the W fiber hinders localized shear bands from propagating and gives rise to multiple shear bands, which results in the enhancement of the compressive strength and plastic deformation.