Sintered silicon nitrides (SSN) & (GPS)&(HPSN) RING
Reaction bonded silicon nitride is made by direct nitridation of a compacted silicon powder, and because of the difficulty of ensuring complete reaction; it is hard to achieve a high component density.
Usual densities are in the range 2.3 – 2.5g/cm3 compared with 3.29g/cm3 for gas pressured sintered silicon nitride.
The higher density gives the HPSN, SSN & GPS-SSN materials better physical properties and means they are used in more demanding applications at very high temperature, especially for non-ferrous molten metal handling and thermocouple sheaths. The nitridation produces only a small volume change, which means that RBSN components do not need to be machined after fabrication and complex near net shapes can be produced in a single process stage.
a. high temperature strength
b. superior thermal shock resistance
c. excellent wear resistance
d. good fracture toughness
e. mechanical fatigue and creep resistance
f. Excellent non-wetting property with good oxidation resistance