Damage Tolerance Analysis on In-plane Compression Strength of Sandwich Structure

The core structure of metal foam composite material will be impacted by various external objects during the actual use, which will reduce the stiffness and strength of the sandwich structure and cause local damage, thus affecting the safety of the sandwich structure. Aiming at the different local damage types of sandwich structures subjected to low velocity impact, the damage tolerance of in-plane compressive strength of metal foam sandwich structures is studied. The residual compressive strength model of sandwich structure is established by finite element simulation method. The validity of the model is verified by comparing the simulation results with the test results. The influence of different damage types on the residual compressive strength of sandwich structure and the size sensitivity of compressive strength to different damage are predicted and analyzed. The results show that dent and delamination are the important factors leading to the reduction of residual compressive strength, that when the model contains delamination damage, the existence of dent will delay the compression failure of the structure, and that for most damage types, the residual compressive strength will decrease with the increase of the sizes.