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The sensitivity and limitations of magnetic coercive field, hardness, metallographic measurements and electron back scattered diffraction analysis are studied and discussed in terms of monitoring recovery and the onset and evolution of recrystallization in a cold rolled low carbon steel. The magnetic coercive field shows much higher resolution than hardness measurements when measuring recovery. Hardness is almost insensitive to the microstructural changes taking place in the material during annealing treatments performed at low temperatures. The conditions under which the magnetic coercive field measurements can also be used to monitor recrystallized fraction are also discussed.

The recovery and recrystallization kinetics of a cold rolled interstitial free (IF) steel were studied during isothermal annealing. Magnetic methods based on coercive field measurements, hardness tests and metallography were applied so as to follow the kinetics experimentally. The coercive field measurement technique reveals a higher degree of resolution for monitoring recovery than conventional hardness determination and also allows the recrystallization progress to be monitored. The results obtained are compared to those previously determined for a non-stabilized extra low carbon (ELC) steel. The observed differences are discussed in terms of the presence of microalloying elements, Ti and Nb, which slow down recovery and delay recrystallization.