Study of ageing in strained ultra and extra low carbon steels by thermoelectric power measurement

The strain aging of extra low carbon steel was studied using thermoelectric power measurement (TEP) technique. The TEP variation due to cold working is a better indicator to assess the dislocation density and the capacity to trap carbon atoms to form Cottrell atmospheres. During aging at a sufficiently low temperature to avoid recovery effects, the TEP measurement allows to follow the disappearance of interstitial atoms from the solid solution, these atoms being trapped by the dislocations introduced by cold rolling.