Casting high-speed steel rolls were first successfully developed by the Japanese in 1988 and used in hot strip rolling mills. The United States began to introduce high-speed steel rolls in the early 1990s, and Europe started relatively late. High-speed steel rolls are generally defined as tool steels that have the ability to maintain hardness during high-speed cutting. As the material of the working layer of the roll, it has high red hardness and high wear resistance during hot rolling. The content of carbon and other forms of carbide alloy elements in high-speed steel rolls is generally greater than 15%, while in tool steel rolls less than 15%. The difference between high-speed steel rolls and semi-high-speed steel rolls is mainly reflected in the difference in alloy content. The content of carbon elements and other carbide-forming alloying elements between the two is nearly doubled.
The widely used cast high-speed steel rolls are mainly produced by three methods: one is the vertical centrifugal casting method, which is used in Europe and North America to produce HSS rolls. The second is the CPC continuous casting method. In Japan, 60%~70% H SS rolls are produced by CPC method, and 30%~40% H SS rolls are produced by centrifugal casting method. The third is the ESR electroslag casting method, which is a method of producing H SS rolls based on the CPC method and adding electroslag purification. Ukraine and Belgium have produced a small amount of rolls by this method.
