Rolling Contact Fatigue (RCF) is a phenomenon that occurs in mechanical components relating to rolling/sliding contact, such as railways, gears, and bearings. It is the result of the process of fatigue due to rolling/sliding contact. The RCF process begins with cyclic loading of the material, which results in fatigue damage that can be observed in crack-like flaws, like white etching cracks. These flaws can grow into larger cracks under further loading, potentially leading to fractures.