Q345C钢连铸板坯热送热装过程中温度场和应力场模拟

考虑板坯钢种弹性模量、导热系数、比热容及线膨胀系数对模拟精度的影响,通过ABAQUS有限元分析软件对Q345C钢250 mm×1500 mm单块连铸板坯冷却过程应力场和温度场进行模拟,经处理得出应力（<20~148 MPa）、温度（769~1000℃）和时间（0~1200 s）三者的关联信息。计算结果表明,板坯空冷温度沿宽度方向分布不均匀,板坯表层边部降温速率0.46℃/s,板坯表层距边部200 mm以外,基本具有相同的温降速率（0.23℃/s）;铸坯堆垛空冷速度较低,约为15℃/h,和现场实测结果吻合。应将连铸坯从火焰切割机到板坯加热炉输送时间降到最短,以及增加保温措施,防止表面热应力过大而形成缺陷。

Simulation of Temperature Field and Stress Field of Steel Q345C Casting Slab during Delivery and Hot Charging Process

Based on considering the effect of slab steel elastic modulus, thermal conductivity, specific heat capacity and linear expansion coefficient on simulation precision, the simulation of stress field and temperature field of steel Q345C 250 mm x 1500 mm single-piece casting slab during cooling process has been carried out by ABAQUS finite element analysis software to get the relative information between stress ( <20 ~ 148 MPa) , temperature (769 ~ 1 000 °C ) and time (0 ~ 1 200 s). Calculated results show that the distribution of temperature of slab along width direction during cooling process is not uniform, the cooling rate of slab surface edge is 0. 46 °C  /s, but the slab distance from slab surface edge more than 200 mm basically has same cooling rate (0. 23  °C /s) ； the cooling rate of slab stacking is rather low, it is about 15 °C  /h, which conforms to measuring results in situ. The convey time from flame cut off machine for casting slab to heating furnace decreases to minimum with adopted holding measures to prevent defects formation being due to excessive thermal stress at slab surface.