How do the materials used in the production of crossed roller bearings affect their performance?

The fundamental material requirements for non-standard bearings are largely determined by their operational performance. The suitability of the materials chosen for manufacturing rolling bearings has a significant impact on their performance and service life. Typically, the primary failure modes for rolling bearings include fatigue spalling—caused by alternating stress—and the loss of precision due to friction and wear. Other causes of premature failure in crossed roller bearings include cracking, indentation, and corrosion. Consequently, the materials used must meet all the stringent requirements for precision crossed roller bearings. Let’s examine the key material requirements for crossed roller bearings:

I. High Contact Fatigue Strength

Contact fatigue failure is the most common form of failure in rolling bearings. During operation, rolling elements move along the raceways of the inner and outer rings, subjecting the contact zones to periodic, alternating loads—sometimes reaching hundreds of thousands of cycles per minute. Under this repetitive stress, fatigue spalling occurs on the contact surfaces. Once spalling begins, it leads to increased vibration and noise, a sharp rise in operating temperature, and ultimately, bearing failure. This process is known as contact fatigue failure. Therefore, steel used for rolling bearings must possess high contact fatigue strength.

II. High Wear Resistance

In addition to rolling friction, sliding friction also occurs during the normal operation of rolling bearings. This sliding friction typically takes place at the interfaces between the rolling elements and the raceways, between the rolling elements and the spacers (or cages), and between the spacers and the guiding flanges of the bearing rings. The presence of sliding friction inevitably leads to wear on bearing components. If the bearing steel lacks sufficient wear resistance, the bearing may prematurely lose its precision; a decline in rotational accuracy can subsequently increase vibration and shorten the service life of the crossed roller bearing. Thus, bearing steel is required to have high wear resistance.

III. High Elastic Limit

When a crossed roller bearing is in operation—especially under heavy loads—the contact pressure at the contact surfaces becomes extremely high. To prevent the bearing steel from undergoing excessive plastic deformation under such high contact stress—which could lead to a loss of precision or the formation of surface cracks—the steel must possess a high elastic limit.

IV. Appropriate Hardness

Hardness is a critical parameter for rolling bearings. It is closely linked to a material’s contact fatigue strength, wear resistance, and elastic limit, all of which directly influence the service life of a crossed roller bearing. The required hardness is generally determined by factors such as the nature and magnitude of the applied loads, as well as the overall dimensions and wall thickness of the bearing. The hardness of the steel used for crossed roller bearings must be carefully optimized; values ​​that are either too high or too low can negatively impact the bearing's service life. For thin-walled crossed roller bearings, the hardness is typically 60 HRC or greater.

Furthermore, for bearings intended for specialized operating conditions, additional performance requirements may be necessary—such as resistance to high temperatures, suitability for high-speed operation, corrosion resistance, or non-magnetic properties. Our company offers customized solutions tailored to specific client needs, including bearings manufactured from specialized materials designed for non-standard equipment.