20MnSi钢筋热连轧及轧后分级控冷过程温度变化模拟

 建立温度计算模型针对22 mm和28 mm规格20MnSi棒材热连轧及控制冷却过程温度场进行了计算机模拟分析，获得了棒材精轧及轧后分级控冷过程的温度变化规律。对轧制圆钢和螺纹钢筋不同条件下成品道次温度变化特点进行了研究。研究结果是，轧制22 mm和28 mm规格20MnSi螺纹钢筋时的终轧温度比轧制相同规格圆钢时显著升高。轧制螺纹钢筋时精轧末道次轧材表层形成螺纹出现较大的局部应变量和应变速率，由此产生大量变形热是终轧钢筋表层急速升温的根本原因。与轧制圆钢相比，为完成同等控冷效果及有效控制轧后组织性能，20MnSi螺纹钢筋精轧后第1水冷段的换热系数明显较高，因此需要相应采用较大的冷却水量。

Simulation of Temperature Change During Hot Continuous Rolling and Multistage Controlled Cooling After Finish Rolling for 20MnSi Steel Ribbed Bar

Temperature field change in the hot continuous rolling and multistage controlled cooling process after finish rolling for 22 mm and 28 mm round bar and ribbed bar of 20MnSi steel were simulated based on the actual measured temperature data. The result shows that the increased temperature at the surface of ribbed bar at the final finishing pass are much higher than that of the round bar for rolling 22 mm and 28 mm 20MnSi steel, which is due to very large local plastic strain and plastic strain rate produced at the surface of 20MnSi ribbed bar during the final finishing pass. Compared to the round bar rolling process, higher heat transfer coefficient and larger water volume are needed for the first stage of water cooling after finish rolling of 20MnSi ribbed bar in order to effectively control the microstructure of final product.