Recently, the light weight and the safety of automobile are the important targets of automotive design and the parts for car have been substituted the plastic or the porous material for the steel material. As the aluminium foam has many pores at its surface, it has the fatigue property of bonded face which differs from general material. In this study, two dimensional model is designed and performed with the fatigue analysis as the variable(θ value) becomes the slant angle of bonded face at the specimen with the aluminium foam. As the analysis result on the models with the slant angles of 6°, 8° and 10°, the bonding forces are disappeared when the fatigue loads are repeated during 4000 cycle, 4500cycle and 5000cycle respectively. By comparing with the analysis results of three models, the fatigue cycle to endure fatigue load becomes larger as the slant bonded angle becomes higher. So, the structural safety can be seen by applying only as only a simulation of finite element method instead of the experiment where much cost and time is spent. In this study, the configuration of aluminum foam is designed with the shape of TDCB Mode II. The shear fatigue strength of the bonded structure can be evaluated by the analysis program of ANSYS.
Tapered double cantilever beam (TDCB) specimens are the most commonly used test configurations to measure the fracture toughness of composites and adhesive joints. The material used in this study is aluminum alloy. For the impact analysis, load and displacement applied from pin onto end block as well as the crack energy release rate are calculated and compared with the finite element analysis results. The energy release rate increases with the velocity increases. As TDCB model with the same condition as experiment is simulated and analyzed, the fracture behavior can be estimated with the analysis result similar to experiment. The simulation results can be agreed with experimental graph and all experimental data at this study can be verified. These experimental results can be applied into real field effectively. It is found that the energy release rates measured from impact tests on the specimens can be predicted by the finite element model suggested in this study.
이중외팔보 모델은 일반적으로 복합재료의 구조테스트와 접착 접합의 테스트에 많이 쓰인다. 본 연구 에서 쓰인 재료는 알루미늄 합금2014이다. 또한 접착 구조물의 접착 면에서 발생한 에너지 해방율 및 유한요소해석을 통하여 알루미늄의 충격에 대한 기계적 특성을 알고자 하는 것이 목적에 있다. 상단부와 하단부의 접착 부위는 하중 점으로부터 100mm 떨어지도록 예비크랙을 두어 접착을 하도록 설계하였다. 하중은 핀에 Y축 방향으로 작용하였다. 충격속도는 7. 5m/s와 12.5m/s로 가하였다. 충격속도가 12.5m/s 일 때의 에너지 해방율은 약 7500J/m2으로 나왔다. 충격 속도가 빠를수록 하중 핀에 가해지는 하중이 증가된다는 것을 알 수 있었으며, 에너지 해방율도 높게 나타나는 것을 알 수 있었다.