Abstract: Tempered martensite can be formed at surface of bar to increase its mechanical properties by higher efficient tube type turbulent flow cooling system after hot rolling of bar products. The temperature field of Φ25 mm Q215 steel bar after hot rolling in turbulent flow process has been analyzed by the finite element analysis software MSC. Marc. Results showed that left turbulent flow system cooling for 1 s the surface temperature of bar decreased from 950.0℃ (finishing rolling temperature) to 768. 0 ℃ and the centre temperature of bar decreased to 861. 2 ℃ ； and as bar was out of turbulent flow cooling system for 3 s the surface temperature increased to 792. 6 ℃. Production application results indicated that the ultimate strength of hot rolled bar cooling by 3 zone turbulent flow cooling was up to 410 MPa while that by normal process cooling was only 310 MPa.

摘要： 利用湍流管式冷却系统可以提高棒材热轧后冷却效率,使棒材表面形成回火马氏体,提高其力学性能。运用有限元分析软件MSC.Marc分析了Φ25 mm Q215钢棒材热轧后湍流冷却过程的温度场。结果表明,棒材离开湍流式冷却系统1 s时,棒材表面由950.0℃(终轧温度)降至768.0℃,芯部温度降至861.2℃;棒材离开湍流式冷却系统后,空冷3 s时表面温度升至792.6℃。生产应用结果表明,棒材进行普通冷却后的强度极限为310 MPa,用湍流式3段冷却后棒材的强度极限达410 MPa。

关键词: 控制轧制, , 湍流冷却, 温度场, 数值模拟