Rolls are the most critical yet vulnerable parts of cold rolling mills. It is crucial for them to withstand long rolling campaigns without losing surface roughness or incurring damage. The newly developed rolls are made from tool-grade steel with high roughness, lower wear, and high damage resistance. One of the most important advantages is the elimination of the need for chrome plating, which is currently widely used on standard steel rolls but is ecologically harmful. We investigated a type of steel containing 8% chromium for use in cold rolling by conducting light optical microscopy, X-ray diffraction analysis, scanning electron microscopy, energy-dispersive spectroscopy, electron backscatter diffraction, hardness testing, and wear resistance evaluations. In this study, a bar with a diameter of 325 mm was electro-slag remelted and forged, machined to a diameter of 315 mm, and quenched and tempered to simulate industrial roll production. After second machining to diameter of 309 mm, a forged roll was induction heated and hardened at four different feed rates (i.e., 24 mm/min, 30 mm/min, 36 mm/min, and 42 mm/min), tempered at 515°C for 24 hours and again at 480°C for 24 hours, and dissected for in-depth analysis. We identified a clear relationship between the feed rate of the roll during induction hardening and the depth of hardness, the sizes of carbides, and the wear properties of the roll. By reducing the feed rate of the roll through the inductor, we increased the depth of the hardened layer from 16 mm (at a feed rate of 36 mm/min) to 25 mm (at a feed rate of 24 mm/min), which is a 56.25% increase expected to extend the lifespan of the working roll without having negative effects on the wear resistance and other important parameters. XRD analysis showed that the sample had a 0.4% residual austenite, which means it had a significantly lower risk of roll damage during operation than standard steel grades.
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