Developments / New materials

METAL OXIDE NANOPOWDERS AND NANOSTRUCTURED CERAMICS

Mechanochemical way to obtain ultrafine oxide and nitride powders with extremely high formability and sinterability has been developed. Low temperature pressureless sintering leads to dense ceramics with gain size within 0.1-0.2 µm.

Technological and economical advantages in comparison with analogs:

• α-Al₂O₃ (mean particle size down to 20 nm, specific surface area up to 105 m²/g, iron content 0.02%, sintered density 98-100% at 1300°C, grain size 0.1-0.2 µm)
• Y-ZrO₂ (mean particle size down to 25 nm, high purity, sintered density 98-100% at 1350°C, grain size <0.2 µm);
• AlN (high purity, oxygen content 0.1%, sinterability up to 98% at 1600°С).
• 20%Al₂O₃ - ZrO₂  dense composite with bending strength more than 1200 MPa.

A “glue” for diffusional welding of ceramics has been developed on the basis of α-Al2O3 nanopowder. Drying and firing conditions being properly selected, the strength of junction is competitive with that of materials to be sticked together.

Feasible applications:

• engineering materials,
• sliding contacts in dry unlubricated conditions
• artificial joints,
• heat conductors for cooling system of high sensitivity apparatus,
• high thermo conductive isolating substrates
• constituents in heat conducting grease and glue
• nanocomposites with extreme mechanical strength