采用抽取中间截面网格拉伸的建模方法, 同时根据前后节点的位置对应关系加载温度数据, 对U71Mn钢重轨轧制全过程中轧件的温度场进行了三维热力耦合有限元模拟; 另外,利用红外线测温仪对不同阶段轧件表层的温度进行在线测量, 并与模拟结果进行对比。结果表明: 形状不规则的重轨截面使得其横截面在轧制过程中的温度分布十分复杂; 随着轧制的进行, 轧件表面尤其是圆角处温度下降剧烈, 心部温度先升高后下降, 最终在轨底和轨头的心部形成两个高温区; 温度的测量结果与模拟结果比较吻合, 验证了有限元模型的有效性。

A thermo-mechanical coupled 3D finite element simulation was carried on the whole rolling passes of U71Mn heavy rail. The model of the rolled-piece was established by extracting and stretching the middle cross-section grid, and the temperature data were loaded according to the corresponding relations of nodes positions before and after. The infrared thermometer was used to carry out the online temperature measurement of the rolled-piece surface and the results were compared with the simulated ones. The results show that the temperature distribution of the rail cross-section was extremely complex because of its irregular shape. As the rolling progress went on, temperature at the surface of the rolled-piece especially corners dropped heavily, temperature raised first and then declined at the heart of rolled-piece, there formed two high temperature area eventually at the middle of the rail head and base. The measured temperature was consistent with the simulated one, this proved the validity of the model.