板厚对不同胶粘剂胶焊单搭接头中应力分布影响的数值分析

采用三维弹塑性有限元分析方法，研究了板厚对胶焊单搭接头中有效应力分布的影响。计算结果表明，板厚对不同胶粘剂胶焊接头中的有效应力分布有不同影响。对酚醛树脂胶粘剂胶焊接头，搭接区边缘应力高于焊点边缘，搭接区边缘是裂纹的起裂位置；随板厚增加，搭接区边缘的峰应力减小而焊点边缘应力变化不大，使应力分布趋于均匀，对提高接头强度有利。对丙烯酸酯胶粘剂胶焊接头刚好相反。

Numerical Analysis of the Effect of Plate Thickness on the Stress Distribution in Weldbonded Joints with Different Types of Adhesives

Using three dimensional elastoplastic finite element analysis (FEA) method, the effect of plate thickness on stress distribution in weldbonded joints with different types of adhesives is analyzed numerically. The weldbonds are made with two types of adhesives, one phenolic resin with higher elastic modulus and the other acrylic resin with lower elastic modulus. Computational results show that the plate thickness has different influences on these two kinds of joints. For the former joints, there exist greater stresses at edge of the lap region than that at edge of the spot. Cracks are initiated there. When the plate thickness increases, stresses at edge of the lap region decrease and that at edge of the spot vary slightly. Stresses in the lap region become more uniform and the joint strength will be improved. For the latter joints, there exist greater stresses at the spot edge than that at lap region edge, so that fracture will begin from the edge of the spot. With the increase of the plate thickness, stresses around the spot increase and that at lap region edge decrease. Stresses in the lap region become more uneven. It is unfavorable to increase the plate thickness in this case.