A novel heat treatment, rapid transformation annealing (RTA), was applied to different low carbon steels (Table 1) using the refining effect of the phase transformation during recrystallisation annealing of cold rolled strip, RTA comprises of rapid heating including a full or partial phase transformation combined with subsequent rapid cooling to ambient temperature. RTA was carried out in different annealing simulators. Firstly, a parameter study was performed in the dilatometer with regard to the maximum grain refinement. Afterwards, the most promising results were applied to the Gleeble annealing simulator in order to produce larger specimens which can be characterised in terms of tensile tests, Thus, a relationship between mechanical properties and grain refinement was identified. After that, pilot RTA trials were performed with HSLA2 MC on the MULTIPAS annealing simulator of Saizgitter Mannesmann Forschung GmbH (SZMF) and with ISO MC on the pilot inductive continuous annealing line of RWTH.
展开▼
