Influence of sintering temperature on Ti6Al4V-Si₃N₄-ZrO₂ ternary composites prepared by spark plasma sintering

In this study, Ti6Al4V-ZrO₂-Si₃N₄ ternary composites were fabricated using a novel spark plasma sintering technique at different temperatures between 950-1200 C, the pressure of 50 MPa, sintering rate of 100 C/min, and a holding time of 10 min to determine the effect of sintering temperature on the consolidated composites. The microstructures of the fabricated composites were examined by the scanning electron microscope (SEM-EDX). The distinct phases and the nano-mechanical properties of the composite were determined by the X-ray diffractometer and nanoindenter. The results show a non-linear response. At elevated temperatures from the composite sample, C_T1-950 C to the composite sample, C_T2-1100 C, the densification, and nanomechanical properties experienced an increase, and when the temperature is elevated to 1200 C, composite C_T3 declines in values. However, the relative density of all fabricated composites was above 95%, which suggests an overall good densification via the spark plasma sintering technique. The ternary composite fabricated at 1100 C, (C_T2) attained maximum values of Vickers hardness, elastic modulus, and nano hardness at 7380 MPa, 177.91 GPa, and 60.06 GPa, respectively, while composite C_T3 declines at 1200 C.