High speed steel (HSS) duplex rolls are manufactured with vertical centrifugal casting process, the shell is HSS with high hardness and excellent wear resistance at high temperature, the core is nodular cast iron with toughness, the comprehensive property is a combination of high wear resistance and toughness.

These rolls are manufactured with high content alloy elements and special heat treatment process, the microstructure of shell is martensite and bainite with plenty of carbides such as MC,M2C and M6C distributed among the matrix, there is only a little hardness drop in the shell. High alloy elements and rehardening give the rolls an excellent wear resistance at high temperature. The outer layer hardness doesn’t show a significant drop until the temperature exceeds 550℃, and the wear resistance is 3-5 times higher than the traditional high NiCr indefinite chilled iron rolls and high Criron rolls.