三维移动式钢板高频感应加热成形电磁-热-力全耦合有限元建模研究

文章基于ANSYS-APDL语言，建立了三维移动式钢板高频感应加热成形电磁—热—力多物理场耦合有限元模型，并使用线圈单元选取法实现了感应线圈热源模型的移动。文中采用此模型研究了Q345钢板在不同加热功率下的变形情况，得到如下结论：钢板加热时受热不均匀，加热区上下表面温差很大最后阶段出现端部效应；随着加热功率的增大，钢板表面瞬时最高温度也增大；加热过程中钢板最大压应力出现在上表面加热区前端，最大拉应力出现在钢板上表面加热区的前方；冷却后钢板最大压应力出现在加热线末端，最大拉应力出现在加热线中段区域；开始时加热区上翘，已加热区冷却下凹，当热源接近末端时，已加热变形区上翘，钢板经过冷却后，整体下凹；随着加热功率的增大，加热区域Y方向变形 Uy越大，钢板弯曲角度线性增大，曲率半径先减小后趋于定值；改进后模型的模拟结果与相同实验参数下的实验结果基本吻合，与传统模拟方法相比更接近实验结果。

Three Dimension Electromagnetic-Thermal-Mechanical Coupling Finite Element Model for High Frequency Induction Mobile Heating Formation of Steel Plate

An electromagnetic-thermal-stress coupling finite element model of multi physics fields is established using the ANSYS-APDL language, in which a coil unit selection method is adopted to realize the mobile induction heating source, a physical environment indirect coupling method to re-alize electromagnetic thermal coupling,and an equivalent substitution indirect coupling method to realize thermal stress coupling. The high frequency induction heating process of the steel plate is simu-lated using this model, and the main conclusions were as follows: Firstly, in the intial stage and ter-mination stage apparent end effect of heating temperature, internal stress and bending deformation are observed. Secondly, in stable heating stage, the heating zone below coil has the highest tempera-ture, and in the thickness direction and width direction pointing to the heating area front there are large temperature gradient and stress gradient. And thirdly, on the surface of the steel plate, the com-pressive stress of heating area and front heat affected zone reaches high temperature yield strength of Q345 steel, so a permanent compression plastic deformation is acquired, then the plate will bend into a concave after cooling. The increase of heating power can make steel plate heating temperature increase, the temperature gradient increases in the direction of plate width, and decreases in the di-rection of thickness, which will prompt larger bending deformation. The above simulation results a-gree with those of the experimental measurement.