Understanding the Role of Nb in Hot-Rolled Rebar: Influence of Final Geometry and Process Parameters
(Room 308)
07 May 19
11:00 AM
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11:30 AM
Microalloying has been widely studied in flat products, but not so much in medium-carbon long products. Multi-pass torsion tests were performed, simulating different hot rolling schedules with two medium-carbon steels (0.24%C), one with 0.03% Nb. Although during initial passes, the behavior was similar to those observed in flat products, in the last passes (very short interpass times), strain accumulation led to the activation of dynamic recrystallization (equiaxed austenite microstructures). The final austenite grain sizes were coarser in the C-Mn steel, especially for higher reheating temperatures and larger diameters. This does not need the application of classical thermomechanical control processes.