Ceramic balls are spherical, rolling elements that provide higher stiffness, lower thermal expansion, lighter weight, increased corrosion resistance, and higher electrical resistance than steel balls. They are made from a variety of ceramic materials.

How Ceramic Balls are Made

Ceramic balls are manufactured by pressing a ceramic powder binder mixture in a preform shape. After the ball is sintered, the part lines are removed via finish-grinding. Lapping and precision finishing is then used to design or grade dimensions and product specifications such as diameter, sphericity, and surface finish.  For applications that require a fully-dense material with specific material properties, hot isostatic pressing (HIP) may be used after sintering. HIP produces ceramic balls with a pore-free microstructure and micron-sized grains.

Applications for Ceramic Balls

The GlobalSpec SpecSearch database contains information about applications for ceramic balls, many of which are used as bearings. The following list provides some examples.

• Ceramic aerospace bearings are used in airframes as well as gyroscopes (gyros), navigation systems, flow meters, avionic instruments, and other aerospace parts.
• Agitator balls have suitable corrosion and density (weight) for agitation or mixing applications, such as the balls used in aerosol paint cans. 
• Ceramic automotive bearings are used with seating tracks and seat slides, safety restraints and seatbelt locking mechanisms, airbags, constant velocity (CV) joints, double offset joints, tripod joints, cross groove joints, spindle bearings, and many other systems.
• Conveyors balls are used in conveyors, ball transfer units, roller table, casters, roller or lazy Susan applications.
• Spring loaded balls are used in quick disconnect couplings or snap on fasteners and fastening systems. Socket wrenches often use this type of fastening mechanism to hold onto the socket.

Ceramic balls are also used in float or level sensing, flow metering, gaging or alignment, valves, sprayers and pumps, and pollution or vapor control systems.

Materials of Construction

Ceramic balls are made of a variety of different ceramic materials. Choices include alumina, alumina-zirconia, aluminum nitride, and aluminum silicate; boron carbide and boron nitride; cordierite and forsterite; carbon and graphite; magnesia, metal boride, silica, and silicon carbide; and zircon, zirconia, and zirconium phosphate. Suppliers of ceramic balls can provide information about the best materials to select for a specific application.