Austenite Grain Growth Behavior and Dynamic Model of ADB790E Hydropower Steel

The growth behavior of austenite grains in ADB790E hydropower steel under the synergistic effects of heating temperature and holding time was studied using in situ quenching and an in situ high-temperature confocal laser scanning microscope (HT-CLSM) system. The experimental results indicate that the size of the austenite grains exhibits a significant coarsening trend as the heating temperature increases and the holding time extends. Based on the experimental data, the Beck’s model and Sellars’ model for austenite grain growth were constructed and compared and analyzed. The predicted grain size values obtained by the models have a strong correlation with the experimental measured values. To verify the accuracy of the model, the predicted values of the model were compared with the in situ observations of HT-CLSM. The results were highly consistent, effectively revealing the growth law of austenite grains of this steel grade during the thermal cycling process.