A high C-high V type alloyed steel roll has been develpoed, which significantly increases wear resistance while maintaining the same productivity as the conventional roll. This paper describes the manufacturing concept of the developed roll and its characteristics: (1) The difference in specific gravity between primary crystals and residual molten steel segregates vanadium-carbides in the inner layer of a roll shell during centrifugal casting. (2) The addition of an appropriate amount of Nb makes the compound carbides of (V, Nb) C, which have a specific gravity similar to that of residual molten steel. (3) The uniform distribution of MC type granular carbides has been achieved in the roll made of 2 mass% C -high V- Nb bearing-type alloyed steel. (4) The increment of tough carbides with the increase in C, Cr and Mo content is effective in suppressing increases in rolling load and in improving the wear resistance of the roll. (5) The developed rolls have wear resistance that is more than 4 times as high as conventional rolls and have been successfully used at the finishing stands of hot strip mills.
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