点焊钛合金蜂窝芯平压性能模拟研究

Study on Compress Simulation of Spotweld Titanium-Alloy Honeycomb Core

在对蜂窝芯力学性能的模拟研究中,常采用将双层壁之间的连接简化为双层壁厚的建模方法,但其不适用于点焊连接的钛合金蜂窝芯。本文提出利用LS-DYNA-EDWELD命令建立点焊连接蜂窝芯有限元模型的方法,对钛合金蜂窝芯进行平压模拟研究。同时,进行了钛合金蜂窝芯的平压力学性能试验,并将平压极限载荷值Fmax与模拟值进行了对比,结果显示点焊连接蜂窝芯有限元模型的平压模拟误差为6.5%,证明了此模型的准确性。最后,应用此模型得到了平压过程中焊点正拉和剪切力随位移的变化关系,研究了焊点正拉和剪切失效强度对蜂窝芯平压力学性能的影响,结果显示焊点正拉失效强度对蜂窝芯平压极限载荷的影响较大。

In the mechanical property simulation study of the honeycomb core, it used to simplify the connection of the honeycomb wall for a plain of double thickness, but it＇s not suitable for spot welding connection of the titanium alloy honeycomb core. By using the LS-DYNA-EDWELD command, we find the finite model in spot welding connection and study the flat pressing simulation of the titanium alloy honeycomb core. In addition, the titanium alloy honeycomb core pressure test is carried out and the pressure load is compared with finite element result, which shows a 6.5% simulation error and proves the accuracy of the finite element model. Finally, the relationship between tensile（shear） strength and displacement is founded and the influence of weld joint tensile and shear strength on pressure load of the honeycomb core is studied based on this model, the result shows that the tensile failure strength has greater influence on pressure load of the honeycomb core than shear strength.