The Design Of TiC Wear-resistant Composites And Its High-temperature Wear And Friction Properties

The new TiC-based cermets materials was employed in many fields mostly aswear resistance materials for it displayed a great number of merits, such as highstrength and hardness, wear corruption and high temperature resistance, goodchemical stability and wear resistance. However, the obvious weakness of theTiC-based cermets materials was brittleness, therefore the improvement of thetenacity was of great importance. In this study, a good combination propertyTiC-bsed cermet with sample composition was prepared.The procedures was as follows:Firstly, TiC-based cermets with different component was prepared by powdermetallurgy method. The microstructure and cross section images of the samples werecharacterized by scanning electron microscopy （SEM）. The mechanical propertieswere tested based on the research of density, bending strength and hardnessexperiments. Secondly, the TiC-based cermets property of friction and wear wasinvestigated under the temperature of25℃,100℃,200℃and300℃, respectively.The property of friction and wear was studied by surface morphologyscanning（SEM） and phase analysis（XRD）. Finally, the thermal-shock resistanceproperty of the TiC-based cermets was studied.The results showed that TiC-based cermets have good density and bendingstrength with the increase of the content of Mo（Ni）. The wear amount was very lowduring the2hours wear test. The biggest amount in all the samples was lower than2.10×10^-12m³. It was found that the friction coefficient was not changed obviously orthe friction stability was good. The major mechanism of TiC-based cermets was: theabrasive wear was the driving force and the adhesive wear was also observed in lowtemperature. The oxidative wear occurred when the temperature reached100℃. Theoxidative wear and the adhesive wear became the mainly wear mechanisms and otherforms of wear appeared when the temperature became more higher. The length ofthermal-shock crack became bigger with the higher temperature of thermal shock andthe times of thermal cycles. The alloy’s content had great influence on the thermal shock resistance of TiC-based cermets. The thermal shock resistance property wasgood with the content of Mo, Ni increasing. To sum it up, The best component ofTiC-based cermets with the comprehensive properties was79%TiC-10%Ni-10%Mo-1%C.