In the diploma thesis, we have investigated the deformability of duplex steel PK338. We have focused on the concrete batch 114825. The basic problem is rolling on a blooming rolling mill, and this steel is difficult to roll on the SIJ Metal Ravne. The problem is the inability to reach high temperatures that would be more suitable for this steel. A Gleeble 1500D thermo-mechanical state simulator was used to illustrate the rolling process. Ten hot compression tests were performed. The tests were performed at temperatures of 1250 ° C, 1200 ° C, 1150 ° C, 1100 ° C, 1050 ° C, 1000 ° C, 950 ° C, 900 ° C, 850 ° C and 800 ° C and strain rates of 1 s-1. The microstructure of deformed samples was studied to determine the optimum rolling temperature. During rolling, we need to avoid the elimination of the sigma phase that occurs at lower rolling temperatures. Thermo-Calc analysis was used to determine which phases are separated according to the rolling temperature. Under these test condition the steel has good workability.
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