SIMPLIFIED PROCESS FOR HOT-ROLLING A STRUCTURAL STEEL WITH TITANIUM AS A MICROALLOYING ELEMENT

摘要

Simplification of the hot-rolling process in a rolling train for structural steels containing Ti and N and with a Ti/N ratio of between 1 and 3, preferably close to 2. The recrystallized austenitic grain size is reduced very little between passes, since the starting point is a very small initial austenitic grain corresponding to the reheating temperature. The present invention proposes a smaller number of passes. The final ferritic grain would be refined by pre-hardening of the austenite, which is achieved by performing the last passes at temperatures close to Ar3, followed by immediate cooling after the passage through the rolling train, at a cooling rate of approximately 20°C/s.