Effect of carbon content and cooling mode on the microstructure and properties of Ti(C,N)-based cermets

Ti(C,N)-based cermets were prepared by vacuum liquid sintering. The effects of carbon content as well as cooling mode on the microstructure, magnetic and mechanical properties of the cermets were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM) and vibrating sample magnetometer (VSM). Hardness and transverse rupture strength (TRS) were also measured. The grains of Ti(C,N)-based cermets became finer and solid solubility of titanium, molybdenum, tungsten in binder phases decreased with increasing carbon content. The thickness of the rim phases increased when the cermet was annealed at 1360 °C for 30 min during cooling, which resulted in the decrease of the hardness and the transverse rupture strength (TRS). On the other hand, the magnetic saturation of Ti(C,N)-based cermets increased with increasing carbon content, which was due to the decrease of the solid solution of alloy elements in binder phases.