CRYSTALLIZATION CHARACTERISTICS AND VISCOUS-FLOW BEHAVIOR OF WC/AMORPHOUS NI73SI10B17 METAL MATRIX COMPOSITES

The crystallization and viscous flow behavior of WC/amorphous Ni73Si10B17 metal matrix composites was examined by using X-ray diffraction, differential scanning calorimetry and thermomechanical analysis. The progress of crystallization is faster in the tungsten carbide (WC)-dispersed composites than in the single-phase amorphous Ni73Si10B17, and the enthalpy of crystallization decreases with increasing volume fraction of the WC particles. It was observed that the activation energy of crystallization of WC-containing samples increased rapidly at almost the same peak temperature relative to the amorphous Ni73Si10B17 alloy. For every composition studied, the viscosity decreased with increasing volume fraction of WC particles; hence the yield stress was raised by increasing the volume fraction of WC particles. T(gi) can be controlled by changing the volume fraction of WC particles.