Ferrule and rolling element materials

The ring and rolling element are usually made of high carbon chromium bearing steel. Most bearings use CCr15, and for bearing rings with larger cross-sections and rolling elements with larger diameters, CCrl5SiMn with good hardenability is used. High carbon chromium bearing steel is an overall hardened steel, which can harden both the surface and core, making it the best material for rolling bearings.

Due to different usage scenarios, certain bearings require materials with special properties, such as impact resistance, high temperature resistance, corrosion resistance, etc.

Carburized bearing steel is usually used for the rings and rolling elements of bearings or large and oversized bearings that withstand impact loads during operation. Carburized bearing steel is carburized within an appropriate depth range on the surface of materials such as chromium molybdenum steel, chromium nickel molybdenum steel, or chromium manganese molybdenum steel, to obtain a dense structure and form a hardened layer. However, the hardness of the central part is relatively low, and it has good impact toughness at the center. Due to its excellent performance, the life calculation of carburized bearing steel is the same as that of high carbon chromium bearing steel.

For bearings that work at high temperatures, high-temperature bearing steel with good heat resistance is used for manufacturing. For bearings that come into contact with corrosive media during work, stainless bearing steel is used for manufacturing.

It is worth noting that the cleanliness of bearing steel, the higher the cleanliness, the less non-metallic inclusions, the lower the oxygen content, and the longer the fatigue life of the bearing. Vacuum degassing or vacuum remelting steel can meet this requirement. Bearings requiring high reliability shall be made of Electro-slag remelting steel.