On the Cu precipitation behavior in thermomechanically processed low carbon microalloyed steels

The present study concerns determination of activation energies of copper-bearing low carbon microalloyed steels processed under different thermomechanical schedules. Selected samples were subjected to 50% cold deformation to examine the effect of prior strain on precipitation of copper. Activation energies were determined by the Kissinger method using differential scanning calorimetry plots obtained at various heating rates. The results are suitably compared with the published results. In view of the results of differential scanning calorimetry, isothermal ageing treatments have been carried out along with suitable microstructural investigations. An attempt has also been made to correlate the variation of hardness and microstructural evolution during ageing treatment. (C) 2009 Elsevier B.V. All rights reserved.