from the conferences organized by TANGER Ltd.
The subject of the study is theoretical modeling for analysis of the microstructure development in progressive droughts of the forging sequence aimed at prediction of the parameters of austenite in as-forged condition, prior to and after direct cooling. Based on numerical calculation of temperature, strain and strain-rate, dynamic recrystallization kinetics were analyzed with use of Johnson-Mehl-Avrami-Kolmogorov (JMAK) model, and the transformed ferrite grain size was calculated, with the use of Hodgson-Gibbs and Sellars-Beynon models. After validation of the theoretical models in a simple upsetting, the results have been verified in the industrial forging process, which allowed assessment of applicability of the employed models in microstructure prediction in reference to hammer-forging of microalloyed steel. The obtained results imply the possibility of the microstructure control in multi-stage hammer-forging process and form the basis for comprehensive selection of the forging process parameters oriented at accomplishment of required microstructure and minimization of the within-part non-uniformity.
Keywords: forging, thermomechanical processing, controlled cooling, microstructure evolution, grain refinement© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.