Study on the Multi-Phase and Multi-Scale Nanocomposite Ceramic Tool Material
An advanced ceramic cutting tool material Al2O3/TiC/TiN is developed by means of adding micro-scale TiC particle and nano-scale TiN particle dispersion. With an optimal dispersing and fabricating technology, this multi-scale and multi-phase nanocomposite may get both higher flexural strength and fracture toughness, especially the fracture toughness may reach to 7.8 MPa·m1/2. The micro-scale TiC particle will form the framework microstructure with other particle and the particles will inlay each other. That is why the flexural strength of Al2O3/TiC composite is improved. Another phase such as nano-scale TiN may lead to fining the grains further more, and promote the sintering to get higher density. The uniform and densified microstructure is obtained, the coexisting transgranular and intergranular fracture mode induced by micro-scale TiC and nano-scale TiN can result in remarkable strengthening and toughening effect.