Generally classified by manufacturing process:
The roll whose working layer is white-faced structure (matrix + carbide) due to the chilling effect of the metal type is called chilled cast iron roll.
Cast iron rolls use the above method, but appropriately increase the carbon content of molten iron to obtain a hemp structure (matrix + carbide + graphite), which is called infinite chilled cast iron rolls. It means that the chill layer has no clear boundary on the fracture.

Using sand-lined metal molds and continuing to increase the carbon content can obtain a roll with a rough hemp structure, which is called a semi-chilled cast iron roll.
In all the above varieties, the graphite is spherical, which is called ductile iron roll. Compound cast rolls add the word “composite”.