Effect of nano-micro TiN addition on the microstructure and mechanical properties of TiC based cermets

In this paper the titanium carbide based cermets with addition of nano-micro titanium nitride were fabricated by conventional powder metallurgy techniques. The microstructure of TiC based cermets with nano-micro TiN addition has been investigated by transmission electron microscope (TEM) and a scanning electron microscope (SEM). Bending strength, fracture toughness and hardness were also measured. Results reveal that mechanical properties do not change monotonously with increasing nano TiN addition. Results also show that nano titanium nitride addition can prevent the coalescence of TiC grains. It is also found that nano TiN is distributed at the interface of TiC/TiC grains and that the growth of TiC grains is impeded by the presence of nano TiN particles and that the result is an increase in mechanical properties. (C) 2002 Elsevier Science Ltd. All rights reserved.