Silicon nitride is a man-made compound synthesized through several different chemical reaction methods. Parts are pressed and sintered by well-developed methods to produce a ceramic with a unique set of outstanding properties. Silicon Nitride ceramic is ideal for bearing parts. Compared with steel, high-performance silicon nitride bearings balls have better mechanical properties under high temperature and could survive from most of the corrosive chemicals.
Comparison of Si3N4 ceramic and Steel for bearing balls
Thermal expansion coeff.
Silicon Nitride Balls Specified for use in such high-technology industries such as full ceramics bearing, hybrid bearings, aerospace, and defense; Silicon Nitride ceramic balls feature these advanced properties:
* Excellent corrosion resistance withstands attack from harsh chemicals and demanding environmental conditions.
* Lightweight Silicon Nitride weighs 60% less than steel which reduces centrifugal force, skidding and wear under high speed and acceleration.
* Superior Surface Finish, Ra 0.17-0.25 microinches may extend L-10 life to as much as 10 times that of steel bearings.
* High-Temperature Hardness is twice that of steel. These all-ceramic balls retain their strength and hardness up to 1800 degrees F.
* Silicon Nitride is further characterized by its low density of 3.2 g/cc, the high flexural strength of 1.0 GPa, and fracture toughness of 6 MPa/M2.
Si3N4 bearing balls have already been applied in automobiles, rockets high-speed engines, equipment working in the corrosive environment and some performance model cars. As the price of ceramic materials decreased, it could have more applications.