Bearings are made of materials such as stainless steel, low-carbon steel, and heat-resistant bearing steel. Stainless steel SUS440C, also known as 9Cr18, is commonly used in damp and polluted environments because it does not rust. It can be widely used in damp and corrosive environments such as medical devices, printing machinery, and food processing. The main advantage of low-carbon steel bearings is their reasonable price, which is suitable for low-speed and light load application scenarios, such as hand carts, casters, sliding doors, manual machinery, etc.

1. High carbon chromium bearing steel

High carbon chromium bearing steel is a bearing specific steel processed by electroslag remelting, with high basic purity, high density, uniform carbonization, fatigue resistance, and wide application. For large bearings or large-section bearings, heavy metal elements such as plutonium and plutonium can also be added to improve quenching and stiffness.

2. Ceramics

Ceramic bearings can be used in extremely harsh environments and special working conditions, such as temperature range, wear resistance, corrosion resistance, insulation, oil-free self-lubricating, high-speed, etc. Ceramic bearings usually have three types: zirconia (ZrO2), silicon nitride (Si3N4), and silicon carbide (Sic).

3. Thermoplastic bearings

Plastic does not rust, and due to its ductility, plastic bearings have strong dust absorption and no noise. Moreover, it has physiological inertness and is suitable for contact with food, commonly used in food processing machinery.

Bearings are components that fix and reduce the load friction coefficient during mechanical rotation. In modern machinery, bearings reduce friction coefficient during power transmission and play an important role in fixing the center position of the shaft. There are four testing methods for bearings: friction and wear test, test bench test, laboratory simulation test, and actual working condition test.

What are the material requirements for bearings, and what are the commonly used materials for bearings?

Due to the fact that rolling bearings are usually used to rotate at a certain speed while bearing a large load with a small contact surface (otherwise bearings are not needed), the material of the bearing is crucial. Generally, fatigue resistance, wear resistance, high hardness, good rigidity, and no deformation are the most basic requirements for rolling elements and rings. In some special scenarios, special bearing materials are required.

So, what are the commonly used materials for bearings?

1、 GCr15 (i.e. 52100) high carbon chromium bearing steel. It is a bearing specific steel that has undergone electroslag remelting treatment, with high purity, high density, uniform carbonization, fatigue resistance, and wide application. For large bearings or large section bearings, heavy metal elements such as manganese or molybdenum are also added to improve quenching properties and rigidity.

2、 SUS440C (i.e. 9Cr18) stainless steel. In some humid and polluted environments, stainless steel bearings are often used, and stainless steel often has high accuracy, making it widely used in damp and corrosive environments such as medical devices, printing machinery, and food processing.

3、 Low carbon steel. The main advantage of low-carbon steel bearings is that they are relatively affordable and suitable for low-speed and light load applications (such as handcrafts, casters, sliding doors, manual machinery, etc.).

4、 Ceramics. Ceramic bearings can be used in extremely harsh environments and special working conditions, due to their wide temperature range, good wear resistance, corrosion resistance, insulation, oil-free self-lubricating, high speed and other characteristics. Ceramic bearings usually have three types: zirconia (ZrO2), silicon nitride (Si3N4), and silicon carbide (Sic).

5、 Carburized bearing steel. There are two ways of carburization, one is surface carburization and the other is penetration carburization.

6、 Heat resistant bearing steel. For metal smelting machinery, long-term treatment of high-temperature conditions requires the use of heat-resistant bearing steel with small softening and size change programs during operation. This type of bearing steel is made of molybdenum or tungsten materials.

7、 Thermoplastic bearings. Plastic does not rust, and due to its ductility, plastic bearings have strong vibration absorption and no noise. Due to their physiological inertness, they are suitable for contact with food and are commonly used in food processing machinery.

8、 Other. In addition to the commonly used materials mentioned above, there are also some bearings made of other materials, such as copper, aluminum, silver, etc., which have different application fields.