Fine ceramics are light and tough. In addition to having excellent insulating properties, they have excellent wear resistance, heat resistance and corrosion resistance.
Taking advantage of these characteristics, our ceramic balls are used in bearings for spindle motors of machine tools, turbochargers, and dental drills that rotate at high speeds. Ceramic balls are also used as check balls in metering pumps for fluid control in water treatment and food applications.
Our ceramic balls are indispensable for creating the future for environmentally friendly applications such as wind power generators, electric vehicles, and semiconductor manufacturing equipment that supports 5G technology.

Fine ceramics are classified into two types, non-oxide and oxide types.
Silicon nitride (non-oxide) and Alumina oxide (oxide type) are the most common materials which are about half the weight of steel and twice as strong.


Silicon Nitride (Si3N4)

Silicon Nitride has excellent mechanical properties for use in Hybrid Bearings (*) such as lower thermal expansion, high rigidity, and wear resistance.

*Hybrid bearings are assembled with ceramic balls and steel rings.

Alumina Oxide (99.5% Al2O3)

Alumina oxide balls have proven capabilities with superior wear performance in corrosive environments and high temperature conditions.


Items Chrome Steel
Silicon Nitride
Alumina Oxide
(99.5% Al2O3)
Density (g/cm3) 7.8 3.24 3.9
Hardness (Hv, 20kg) 772 – 900 1,500 1,600 – 1,700
Coefficient of thermal expansion (x10-6/℃) 12.5 3.0 8.2 – 9.0
Max. use temperature (℃) 160 800 1,400

The above values are typical values.