Bearing rust is related to its material and operating environment. Bearing steel itself contains carbon, which reacts with moisture. To prevent bearings from rusting, rust prevention treatment is necessary. Alternatively, non-steel bearings can be used. Metal products are prone to rusting after oxidation, and stainless steel bearings are no exception. Many factors influence rust formation, such as the chemical composition and structure of the metal itself; surface finish (oxygen concentration difference corrosion); the composition and pH value of the solution in contact with the metal surface; and the environment in which it is located. These are all direct factors causing bearing rust. Furthermore, when using bearings, avoid direct contact with your hands. When sweat comes into contact with the bearing, a sweat film forms on the surface, which can cause electrochemical reactions and corrode the bearing. Therefore, use dedicated gloves or finger cots to handle bearings, and avoid direct contact with your hands.