Microstructure and mechanical properties of silicon nitride–titanium nitride composites prepared by spark plasma sintering

Abstract

▶ Si 3 N 4 –TiN composites were successfully prepared by using Spark Plasma Sintering . ▶ Homogeneous distribution of equiaxed TiN grains in Si 3 N 4 matrix for SPS1 (1550 °C). ▶ High hardness value (21.7 GPa) and bending strength (621 MPa) for SPS1 (1550 °C). ▶ Highest fracture toughness value (8.39 MPa m 1/2 ) SPS2 (1300 °C). Si 3 N 4 –TiN composites were prepared by spark plasma sintering (conventional sintering (SPS1) and in situ reaction sintering (SPS2)). Homogeneous distribution of equiaxed TiN grains in Si 3 N 4 matrix results in the highest microhardness (21.7 GPa) and bending strength (621 MPa) of sample SPS1 sintered at 1550 °C. Dispersion of elongated TiN grains in Si 3 N 4 matrix results in the highest fracture toughness (8.39 MPa m 1/2 ) of sample SPS2 sintered at 1300 °C.