Hwang Joong-Ki
School of Mechatronics Engineering, Korea University of Technology & Education, Cheonan 31253, Republic of Korea.
Materials (Basel). 2023 Dec 11;16(24):7598. doi: 10.3390/ma16247598.
The effect of latent heat via phase transformation on the thermal behavior of a billet was investigated during the heating process. The latent heat of the billet strongly affected the temperature distribution of the billet during heating, although the heating rate of the billet was not high during the process. The temperature profile of the center region of the steel billet with latent heat had a strong flat shape compared with the other regions, as the heat supply to the center region was limited during the heating process owing to the finite thermal conductivity and mass effect of the billet. The latent heat by phase transformation typically occurred in the middle stage of heating, and the latent heat increased the temperature deviation of the billet during heating owing to the delay in the temperature rise at the center region of the billet. During the phase transformation of carbon steels during heating, the gas temperature needs to be low to reduce the temperature deviation or thermal stress of the billet. Industrial hot rolling mills are required to consider the latent heat by phase transformation of the billet to properly design the heating pattern for the billet. The heating pattern in the reheating furnace should be varied with the materials to obtain a high heating quality for the billet.
研究了在加热过程中，相变潜热对钢坯热行为的影响。尽管在此过程中钢坯的加热速率不高，但钢坯的潜热在加热过程中对钢坯的温度分布有强烈影响。由于钢坯的有限热导率和质量效应，在加热过程中向中心区域的热量供应有限，因此具有潜热的钢坯中心区域的温度分布与其他区域相比呈现出强烈的平缓形状。相变潜热通常发生在加热的中间阶段，由于钢坯中心区域温度上升延迟，潜热增加了加热过程中钢坯的温度偏差。在碳钢加热过程中的相变期间，需要较低的气体温度以减小钢坯的温度偏差或热应力。工业热轧机需要考虑钢坯相变潜热，以便为钢坯正确设计加热模式。加热炉中的加热模式应根据材料而变化，以获得钢坯的高加热质量。
