框桁式火箭贮箱壁板结构激光焊接变形仿真研究

针对框桁式火箭贮箱壁板结构双激光束双侧同步焊接（DLBSW）变形开展仿真研究。首先，建立了框桁式火箭贮箱壁板结构DLBSW有限元模型，并通过试验验证了该模型的可靠性；其次，重点考察了焊接顺序与方向对框桁式火箭贮箱壁板结构激光焊接变形的影响，获得了变形控制策略；最后，采用该优化方案，成功完成了框桁式火箭贮箱DLBSW壁板的研制。结果表明，采用“交叉中心焊”的焊接顺序，可极大程度地降低焊接变形；在焊接顺序优化的基础上，改变中间三条焊缝的焊接方向，可进一步降低焊接变形。

Simulation Research on the Laser Welding Deformation of Frame-truss Tank Wall Structure in Launch Vehicle

In this paper, the simulation research about deformation after dual laser-beam bilateral synchronous welding (DLBSW) for the frame-truss tank wall structure is conducted. Firstly, the finite element model of DLBSW for the frame-truss tank wall structure is established,and verified by experimental results. Subsequently, the effect of welding sequence and direction on the deformation of frame-truss tank wall structure fabricated by DLBSW is emphatically investigated to obtain the deformation control strategy. Finally, the frame-truss tank wall structure is successfully manufactured by DLBSW with the optimized scheme. The results show that the welding deformation is greatly reduced under the welding sequence of "cross center welding". Based on the optimized welding sequence, the welding deformation can be further reduced by changing the welding direction of the middle three welds.