Abstract: The finite element simulation of heat transfer during heating of 250 mm x 280 mm x 6 000 mm concasting billet of 0.72C-1.30Mn high carbon steel U71Mn has been carried out and by non-linear regression analysis, the mathematical model for relation between decarburization depth d (mm) of steel billet with decarburization depth d₀(mm) before reheating, surface temperature T (K) of billet and reheating time: d=d₀+(2.132×10^-7T²-0.0002T+0.0163)·(0.208 t^0.5-d₀) is obtained. Hie measured results showed that the relative prediction error was ≤3.2% . Based on calculation by the model, it is obtained that the optimum reheating procedure is 1150 °C for 86 min at preheating zone, 1250 °C for 131 min at heating zone and 1230 °C for 68 min at soaking zone. The examination results showed that using optimum reheating procedure the decarburization of products decreased about 20%.

Key words: Finite Element Method, Casting Billet, Temperature Distribution, Decarburization Depth, Prediction Model

摘要： 进行了0.72%C-1.30%MnU71Mn高碳钢250 mm×280 mm×6000 mm连铸坯加热时的传热有限元模拟和通过非线性回归分析,得出钢坯在加热后钢坯脱碳深度d (mm)与加热前脱碳深度d₀ (mm)、钢坯表面温度 T(K)和加热时间 t (min)之间关系的数学模型: d=d₀+(2.132×10^-7T²-0.0002T+0.0163)·(0.208 t^0.5-d₀)。实测结果表明,模型的相对预报误差≤3.2%。根据模型计算得出铸坯的优化工艺为预热段1150℃ 86min,加热段1250℃ 131min,均热段1230℃ 68min。检验结果表明,采用优化工艺,成品脱碳深度可降低20%左右。

关键词: 有限元模拟, 铸坯, 温度分布, 脱碳深度, 预报模型