What properties should tapered roller bearing materials have?

1. Friction compatibility.

The performance of preventing adhesion and boundary lubrication when the shaft diameter is in direct contact with the bearing bush. The material factors that affect the friction compatibility of friction pairs are:

(1) the degree of difficulty of forming sub-materials to form alloys in metallurgy.

(2) the affinity between materials and lubricants.

(3) the friction factor of the pair material without lubrication.

(4) the microstructure of the material.

(5) Thermal conductivity of the material.

(6) the surface energy of the material and the characteristics of the oxide film.

2.Clamp property.

The ability of the material to allow foreign hard particles to be clamped in to prevent scratches or abrasive wear. For metallic materials with low hardness and low elastic modulus, the clamping property is good, while non-metallic materials are not necessarily, such as carbon graphite, the elastic modulus is lower, but the clamping property is not good. Tapered roller bearings usually use softer materials and harder materials to form the friction amplitude, and generally use softer materials as bearings.

3. Running-in property.

In the process of running-in between shaft diameter and bearing bush, the machining error, coaxiality error and surface roughness parameter values of shaft diameter and bearing bush are reduced, so that the contact is uniform, thus the friction force and wear rate are reduced.

4. Friction compliance.

The material compensates for the poor initial fit of the sliding friction surface and the flexural properties of the shaft by the elastic-plastic deformation of the surface. The material with low elastic modulus has better compliance.

5. Wear resistance.

The ability of a pair of materials to resist wear. Under the specified wear conditions, the wear resistance is expressed by the wear rate or the reciprocal of the wear degree and the wear amount.

6. Fatigue resistance.

The ability of a material to resist fatigue failure under cyclic loading. At the service temperature, the strength, hardness, impact strength and microstructure uniformity of bearing materials are very important to resist fatigue. Materials with good running-in and clamping properties usually have poor fatigue resistance.

7. Corrosion resistance.

The ability of a material to resist corrosion. When used in the atmosphere, lubricating oils will gradually oxidize and produce acidic substances, and most lubricants also contain extreme pressure additives, which will corrode FAG bearing materials, so tapered roller bearing materials need to have corrosion resistance.

8. Gas corrosion resistance.

When the solid moves relative to the liquid, when the bubble in the liquid breaks near the solid surface, it will produce local impact high pressure or local high temperature, which will lead to cavitation wear. The ability of materials to resist cavitation erosion is called cavitation resistance. Generally, copper-lead alloy, tin-based FAG tapered roller bearing alloy and Al-Zn-Si alloy have good cavitation resistance.

9. Compressive strength.

The ability to withstand unidirectional loads without being crushed or dimensionally unchanged.