ndefinite Roll is cast using such proportions of silicon, chromium, nickel and molybdenum that the working face is no longer completely white but contains a small amount of very finely divided graphite flakes gradually increasing from face to core with corresponding decrease in the amount of carbide. The transition from Chill to graphite being more smooth, the gradual change in hardness associated with the indefinite-chill structure allows deeper grooving.

ndefinite Roll is cast using such proportions of silicon, chromium, nickel and molybdenum that the working face is no longer completely white but contains a small amount of very finely divided graphite flakes gradually increasing from face to core with corresponding decrease in the amount of carbide. The transition from Chill to graphite being more smooth, the gradual change in hardness associated with the indefinite-chill structure allows deeper grooving.