As we all know, normal bearings are made of steel, while ceramic bearings are made of silicon nitride, which belongs to the category of ceramic materials. Low rolling resistance is the most important selling point of ceramic bearings. Due to the intrinsic nature of the material, ceramic bearings can be made more round, the surface is smoother, ball size tolerance is also smaller, means lower energy loss. At the same time, the hardness of ceramic bearings is about 30% higher than that of steel bearings, so they should be more durable. In addition, ceramic bearings do not corrode or rust, so they also require less maintenance.
Most ceramic bearings for bicycles are actually two-material bearings, using a steel housing and ceramic bearing balls. Full ceramic bearings, on the other hand, use ceramic bearing rings, which are lighter and have the lowest rolling resistances, although they are less durable. There is also a category of non-sealed ceramic beads that can be used to upgrade bike parts that are paired with non-deep groove ball bearings, such as bead gear hubs.
However, ceramic bearing is expensive!
Let's start with the advantages of ceramic bearing:
1, The degree of corrosion is small. Can withstand the corrosive working environment.
2, Temperature change tolerance. High and low temperatures switching on ceramic bearings have no effect.
3, Not easily deformed. Ceramic modulus of elasticity is higher than steel, so it is rarely deformed by force.
4, Long service life. Ceramic rolling ball density is lower than steel, and light in weight naturally, so it can reduce the friction generated by the centrifugal force of the outer ring of the rotation, and the service life becomes longer.
Here are some of its shortcomings:
1, Processing difficulties. Ceramic bearings have a low bearing capacity, compared with the metal material which is sensitive to thermal shock. So in the processing of ceramic bearings, the processing steps are very complex, there are many factors to consider, so one of the disadvantages of ceramic bearings is difficult to process.
2, High cost. Ceramic bearings are non-metallic, non-ferrous materials, a non-magnetic excellent insulator, bearing material cost is relatively high. At the same time, ceramic bearing processing and grinding costs are very complex, the production cost is also very high. Therefore the current ceramic bearing, the most obvious disadvantage is the high cost. This is also the main reason why it is expensive.