炸药覆盖层对爆炸焊接影响的数值模拟

为探究炸药覆盖层厚度对爆炸焊接的影响，采用ANSYS/LS-DYNA软件并结合SPH-FEM耦合算法，对不同覆层厚度下的爆炸焊接试验进行三维数值模拟.文中采用厚度为20 mm的Q235钢和厚度为2.5 mm的304不锈钢作为基板和复板.根据相应的材料参数理论计算了焊接过程中的动态参数，并以此建立爆炸焊接窗口.仿真结果表明，与无覆盖层爆炸焊接相比，覆盖层厚度为15 mm、 30 mm和45 mm时冲击速度分别提高了39.3%, 58.1%和68.8%，碰撞压力分别增大了41.0%, 65.6%和80.6%.仿真结果与试验结果基本一致.利用SPH法进行二维数值模拟，得到了装配炸药覆盖层时复板与基板的复合界面.仿真结果表明，复合板在覆层厚度为15 mm时具有良好的波形复合界面，且界面波形与试验金相分析结果较为吻合.

Numerical simulation research on the effect of explosive covering on explosive welding

In order to research the influence of covering thickness on explosive welding, the explosive welding experiments under different covering thickness are simulated in three dimensions by using ANSYS/LS-DYNA software and combining the SPH-FEM coupling algorithm. The Q235 steel with the thickness of 20 mm and the 304 stainless steel with the thickness of 2.5 mm are used as the base plate and the flyer plate in the present study. The dynamic parameters in the welding process are calculated according to the corresponding material parameter theory, and an explosive welding window is established. The simulation results show that, compared to the explosive welding without covering, the impact velocity is increased by 39.3%, 58.1% and 68.8% respectively when the covering thickness is 15 mm, 30 mm and 45 mm. And the collision pressure is increased by 41.0%, 65.6% and 80.6% respectively. The simulation results approximately agree with the experimental results. The SPH method is used to carry out two-dimensional numerical simulation to obtain the composite interface between flyer plate and base plate when assembling covering. The simulation results show that the composite plate has a good waveform composite interface when the covering thickness is 15 mm, and the interface waveform is more consistent with the results of the metallographic analysis in the experiment.