The variations of thermoelectric power (TEP) measurements during annealing of warm and cold rolled extra low carbon (ELC) steels were analysed. Where a prominent influence of recovery was detected in cold rolled steels during annealing, almost no variation of TEP due to both recovery and recrystallisation was observed during annealing of warm rolled steels. On the other hand, TEP measurements were proven to be a powerful technique to monitor dissolution of cementite and precipitation of aluminium nitrides. It was found that these two phenomena significantly affect TEP measurements and recrystallisation kinetics during annealing of warm rolled steels.

During continuous heating of a cold rolled low carbon (LC) steel a dilatometric anomaly has been detected previous to the well known ferrite-to-austenite transformation. This anomaly is due to the texture change and/or the dislocation annihilation that accompany the recrystallization process.

No abstract

The recrystallisation behaviour of two cold-rolled low carbon microalloyed steels with different Ti content was investigated by thermoelectric power (TEP) measurements and metallography. It was shown that recrystallisation was more sluggish in the higher Ti grade steel as compare with traditional ELC and LC steels. The existence of Ti in solid solution together with the pinning effect of Nb-, V- and Ti-rich particles are likely to be responsible for such behaviour. Metallographic etching with picral revealed that cementite act as preferential nucleation site for recrystallisation.