
The hot rolling rolls of a rolling mill are usually heated using a heating furnace. The working temperature of hot rolling rolls is usually between 700 ℃ and 800 ℃, which requires strong rolling force and the surface to withstand the wear of the rolled material. They are repeatedly heated and cooled by the hot rolling material and subjected to thermal fatigue with large temperature changes. Therefore, hot-rolled roll materials must have high hardenability, low coefficient of thermal expansion, high thermal conductivity, high high-temperature yield strength, and wear resistance. High chromium cast iron rollers have good thermal cracking resistance due to the formation of a dense and tough chromium oxide film on the surface of the rollers, which can reduce the number and depth of thermal cracks.