During the use of high-speed steel rolls, under good cooling conditions, a thin and dense oxide film is formed on the surface of the roll body. This uniform, thin and dense oxide film can exist for a long time without falling off, so that the wear resistance of the high-speed steel roll is significantly improved.

• High-speed steel rolls have good thermal stability, and the roll surface has high hardness and good wear resistance at rolling temperature.
• The high-speed steel roll has good hardenability, and the hardness from the surface of the roll body to the inside of the working layer hardly decreases, thus ensuring that the roll has the same good wear resistance from the outside to the inside.

It can be seen from the metallographic photos that the metallographic structure of the high-speed steel roll is much better than other materials in terms of the shape, quantity, size and distribution of carbides, as well as the matrix structure and grain size.