Fabrication of W-ZrC nanocomposite through reaction sintering using relatively low-toxic methacrylamide-based system

In this study, performs were fabricated using mixture of tungsten carbide (WC), zirconium oxide (ZrO2) and carbon black powders by gel-casting process based on methacrylamide system. HSC Chemistry software was employed to study the thermodynamic conditions of reactive sintering. Gel-cast green bodies were dried at 500 degrees C for 1 h and then reactively sintered at 2150 degrees C for 3 h to produce W-ZrC composites. The influence of monomer ratio and volume fractions of the loaded solid on the flexural strength of dried green bodies was evaluated. Results revealed that an optimal molar ratio, which leads to improving the reactivity of the sintering process, was 3: 1 between WC and nanoZrO(2) powders. The phases, microstructures, and physical properties of the W-ZrC composites were investigated by x-ray diffractometer (XRD), scanning electron microscope (SEM), Vickers hardness tester and pulse-echo technique. XRD results and SEM micrographs indicated that W-ZrC composite has been successfully produced by this method. The mean values of hardness and elastic modulus of the W-ZrC composites were in the ranges of 4.95 +/- 0.15 GPa and 360 +/- 2 GPa, respectively.