Si3N4 alpha phase, si3n4 ceramic powders, si3n4 powder for bearings
Spec: alpha: 100-200nm. We could also supply beta phase si3n4 powder, 99.9-99.99%, any interested, feel free to contact us.
Application for si3n4 ceramic powders:
The longer stacking sequence results in the alpha phase having higher hardness than the Beta phase.
However, the alpha phase is chemically unstable compared with the beta phase. At high temperature
when a liquid phase is present, the alpha phase always transforms into the beta phase. Therefore,
beta si3n4 is the major form used in si3n4 ceramics.
One of the major applications of sintered silicon nitride is in automobile industry as a material
for engine parts. Those include, in diesel engines, glowplugs for faster start-up;
precombustion chambers (swirl chambers) for lower emissions, faster start-up
and lower noise; turbocharger for reduced engine lag and emissions.
In spark-ignition engines, silicon nitride is used for rocker arm pads for lower wear,
turbocharger for lower inertia and less engine lag, and in exhaust gas control valves for
increased acceleration.
Silicon nitride bearings are both full ceramic bearings and ceramic hybrid bearings with balls
in ceramics and races in steel. Silicon nitride ceramics have good shock resistance compared to
other ceramics. Therefore, ball bearings made of silicon nitride ceramic are used in performance
bearings.
Silicon nitride has long been used in
high-temperature applications. In particular, it was identified as one of the few monolithic
ceramic materials capable of surviving the severe thermal shock and thermal gradients generated
in hydrogen/oxygen rocket engines.
