The Fact is...
In principle, the production of corrosion-resistant steels today does not pose a great challenge.
However, the use of these steels in rolling bearings puts other, important aspects into focus.
Although conventional martensitic stainless steels usually achieve the necessary corrosion resistance, they often do not convince in noise-sensitive applications and due to the lower hardness, they also have a lower fatigue life.
This is because chromium-concentrated eutectic carbides form during the production of the steels. These so-called grain boundary carbides are metal carbon compounds that settle during the cooling process mainly on the edge areas of the bearing steel which could lead to the material weakening. The carbides impair the surface quality of the raceways and contribute to an increased natural frequency of the bearings, ultimately leading to a premature wear and an increased running noise.
SBN Wälzlager offers you products that have been developed and optimized to meet the extreme demands of corrosion. We paid attention to optimizing the equilibrium between the carbon content, chromium content and the nitrogen content when using these steels. As a result, these steels no longer form any troublesome eutectic carbides and at the same time are extremely high corrosion-resistant. Tests have shown that the hardness and thus the load capacity of these steels is comparable to that of conventional bearing steels (100Cr6).
In certain product families e.g., angular contact ball bearings, tests, done with lubrication with water, have shown a twenty-five times longer service life and five times longer service life in lubrication with oil compared to standard stainless steels
"In addition, we also have bearings made of high-nitrogen martensitic steels (HNS). They are significantly superior to conventional corrosion-resistant steels in terms of wear resistance and corrosion resistance. Moreover, austenitic chrome-nickel steels with the highest chemical resistance and antimagnetic behavior. These are unbeaten regarding corrosion resistance, but have a lower hardness and thus capacity. "