566 / 2019-03-20 17:50:08

Mechanical properties of TiO2 Nanoceramic through High Pressure Sintering

Nanoceramic; High pressure sintering; Hardness

全体主题 > High Pressure Physics and Materials Science

Titanium dioxide (TiO2) has a wide range of applications in photocatalysis, nanoceramics, gas sensors and electronic devices due to its unique physical and chemical properties. At present, the research of TiO2 nanoceramic is mainly focused on mechanical properties, including hardness, fracture toughness and low-temperature ductility. The conventional preparation method for preparing TiO2 nanoceramic is to directly use TiO2 nanopowders as a precursor, through pressureless sintering, hot press sintering, spark plasma sintering or high pressure sintering. However, the large specific surface area of the nanoparticles makes them extremely agglomerated during the sintering process and adsorbs impurities. Therefore, the obtained TiO2 nanoceramic blocks are loose with large crystal grains and excessive pores, resulting in poor mechanical properties.
At this work, the submicron anatase-TiO2 was used as the precursor through high pressure sintering. The sintering law has been studied, as well as the mechanical properties such as microhardness and fracture toughness. The experimental results show that the high pressure environment can lower the synthesis temperature, and inhibit the growth of crystal grains. Therefore, the obtained dense TiO2 nanoceramics bulk achieved a higher hardness of 13.5GPa than ordinary TiO2.