ANNAN Kofi University of Pretoria

Spoluautoři SIYASIYA Charles, STUMPF Waldo, BANKS Kevin, TULING Alison

The effect of thermomechanical processing (TMP) parameters on grain growth in five low C - Mn microalloyed steels with varying compositions of Nb, Ti and V were studied. In order to locate a reasonable heating system, the precipitation and solubility behaviour of the five low C - Mn microalloyed steels were modelled using Thermocalc. Austenitizing temperatures between 1100 oC and 1250 oC and holding times ranging from 0 to 2 hours were employed in the study. The data obtained from the measurement of the average grain size from the heat treatment were analysed by adapting standard theory to account for the initial austenite grain size generated when the steel becomes fully austenitic. The classical grain growth equation by Cellars and white man was employed in determining the grain growth equation constants namely n; Q and A. The determined constants were then used in modelling a grain growth equation for the tested microalloyed steels. The predictive potential of the model is very well in agreement with the experimental data.