The structure of the rolls are Steel based i.e. formed by melting Mild Steel (MS) and other alloys. After casting the hardness of the roll is on the higher side due to added alloys so it is decreased by a process of annealing. The carbon content for these rolls is in between that of MS and cast iron close to 1.2 – 2.10.
| MATERIAL | HARDNESS | C | MN | SI | S | P | NI | CR | MO |
| Alloy Steel | 40-50 | 1.20-2.00 | 0.40-1.20 | 0.65 MAX | 0.050 MAX | 0.050 MAX | 0.50-1.30 | 1.00/1.50 | 0.20-0.50 |
| Adamite | 45-50 | 1.70-2.10 | 0.50-1.10 | 0.75 MAX | 0.050 MAX | 0.050 MAX | 0.80-1.60 | 1.00/1.70 | 0.20-0.60 |
| 50-55 | 1.80-2.20 | 0.60-1.20 | 0.65 MAX | 0.050 MAX | 0.050 MAX | 0.90-1.70 | 1.10/1.80 | 0.25-0.60 |
