(1) Forming alloys to change the internal structure of iron. For example, adding metals such as chromium and nickel to ordinary steel to make stainless steel greatly increases the rust resistance of steel products

(2) Covering the surface of iron products with a protective layer is a common and important method to prevent rust. According to the composition of the protective layer, it can be divided into the following types:

a. Coating mineral oil, paint, or firing enamel, spray coating, etc. on the surface of iron products. For example, cars, buckets, etc. are often coated with paint; Machines are often coated with mineral oils, etc

b. A layer of rust resistant metals such as zinc, tin, chromium, nickel, etc. can be plated on the surface of steel by electroplating, hot plating, and other methods. These metal surfaces can form a dense oxide film to prevent rust from coming into contact with iron products and substances such as water and air

c. Using chemical methods to form a dense and stable oxide film on the surface of iron products to prevent rusting

(3) Maintaining the cleanliness and dryness of the surface of iron products is also a good way to prevent rusting