A modified heat transfer and material transfer model was investigated for friction stir welding of DH36 steel by considering the Eulerian framework in steady state. During this analysis, temperature-dependent properties of the workpiece and the tool material were used. The material viscosity was modelled as a non-Newtonian viscoplastic fluid depending on the temperature and flow stress. The heat generation at the tool workpiece interface incorporated the partial sticking and partial sliding condition. An asymmetric and skewed temperature distribution at the advancing trailing side was observed. Asymmetry of temperature distribution was increased with an increase in the tool traverse speed. It was observed that the temperature was maximum at the interface between the shoulder and tool, and the peak temperatures decreased non-uniformly along the thickness direction. The results of material flow analysis indicated that the hot plasticized material flew ahead the tool along the retreating side in counter-clockwise direction, passed the tool and got released behind the tool during the welding stage. There existed a swirl region on the advancing side which was highly prone to defect formation. The temperature field and plastic flow field of the computational model matched satisfactorily with the experiment results.

考虑到稳态下的欧拉框架，研究了一种改进的传热和材料传递模型，用于DH36钢的摩擦搅拌焊接。在此分析过程中，使用了工件和工具材料随温度变化的特性。根据温度和流动应力，将材料粘度建模为非牛顿粘塑性流体。工具工件界面处的热量产生了部分粘着和部分滑动的情况。在前进的后侧观察到不对称且倾斜的温度分布。温度分布的不对称随着刀具移动速度的增加而增加。观察到肩部和工具之间的界面处的温度最高，峰值温度沿厚度方向不均匀下降。材料流动分析的结果表明，热塑化材料在逆焊时沿逆时针方向沿退刀面飞过刀具，通过刀具并释放到刀具后面。在前进侧存在涡旋区，极易形成缺陷。计算模型的温度场和塑性流场与实验结果吻合良好。在前进侧存在涡旋区，极易形成缺陷。计算模型的温度场和塑性流场与实验结果吻合良好。在前进侧存在涡旋区，极易形成缺陷。计算模型的温度场和塑性流场与实验结果吻合良好。