고탄소강의 열간압연 공정의 냉각대에서의 온도 예측모델 정도 향상 = Temperature prediction during phase transformation of high C steel in run-out table of hot-rolling mill

다국어 초록 (Multilingual Abstract)

To improve the accuracy of temperature prediction of high carbon steel in ROT of hot-rolling mill, the influencing factors in temperature calculation such as transformation kinetics and enthalpy change were investigated using heat equation. The transformation kinetics was measured with dilatation curve and compared to the calculated one by current model. Enthalpy change was attempted to measure. It was successful at a specific temperature, but not measurable at the lower temperature due to an experimental limitation. Enthalpy change data from the model was compared to the one from the recently released thermodynamic database. It was proved that inaccurate evaluation of transformation kinetics is mainly responsible for incorrect temperature prediction, besides, reliability on thermodynamic quantities such as enthalpy change associated with the phase transformation needs to be improved for better temperature prediction. This study reveals that vigorous consideration of transformation kinetics and thermodynamic quantity will provide better accuracy in temperature prediction in particular high carbon steel.

목차 (Table of Contents)

• 1. Introduction
• 2. Literature review
• 2.1. Microstructure models in hot-rolling process
• 2.2. Basic theory for the temperature prediction model
• 2.3. Inaccuracy of a temperature prediction model
• 2.4. Contribution factors on phase transformation kinetics
• 3. Experimental
• 3.1. Chemical composition and phase diagram of sample
• 3.2. Measurement on the heat released during isothermal phase transformation
• 3.3. Simulation of a temperature prediction model
• 3.4. Actual phase transformation kinetics
• 3.5. Verification of the enthalpy data used in the model
• 4. Result and discussion
• 4.1. Heat release during isothermal phase transformation
• 4.2. Verification of the transformation kinetics
• 4.3. Verification of the enthalpy data
• 5. Conclusion
• Reference