No abstract

This paper aims to propose a temperature-dependent cohesive model to predict the delamination of dissimilar metal–composite material hybrid under Mode-I and Mode-II delamination. Commercial nonlinear finite element (FE) code LS-DYNA was used to simulate the material and cohesive model of hybrid aluminium–glass fibre-reinforced polymer (GFRP) laminate. For an accurate representation of the Mode-I and Mode-II delamination between aluminium and GFRP laminates, cohesive zone modelling with bilinear traction separation law was implemented. Cohesive zone properties at different temperatures were obtained by applying trends of experimental results from double cantilever beam and end notched flexural tests. Results from experimental tests were compared with simulation results at 30, 70 and 110 °C to verify the validity of the model. Mode-I and Mode-II FE models compared to experimental tests show a good correlation of 5.73% and 7.26% discrepancy, respectively. Crack front stress distribution at 30 °C is characterised by a smooth gradual decrease in Mode-I stress from the centre to the edge of the specimen. At 70 °C, the entire crack front reaches the maximum Mode-I stress with the exception of much lower stress build-up at the specimen’s edge. On the other hand, the Mode-II stress increases progressively from the centre to the edge at 30 °C. At 70 °C, uniform low stress is built up along the crack front with the exception of significantly higher stress concentrated only at the free edge. At 110 °C, the stress distribution for both modes transforms back to the similar profile, as observed in the 30 °C case.

No abstract

Thin-walled structure is one of the common structures that is widely used as an energy absorber due to inexpensive, high availability and lightweight. Moreover, the multi-cell structure is known as a useful method to elevate the effectiveness of thin-walled structures in crashworthiness. Energy absorber performance of multi-cell thin-walled tube structure is known to be greater than the single thin-walled tube. This is due to the limitation of plastic hinge zones of single tube during lateral loading condition. This paper presents the effect of multi-cell configuration on energy absorption responses under lateral loading condition. Experiment and numerical approach were used in this research. The validation of finite element model (FEM) was conducted by comparing the load-displacement responses and deformation mode of a quasi-static compression test. Multi-cell configuration study was performed to identify the energy absorption performance of multi-cell thin-walled tube with different arrangements. The results reveal that an increasing number of cells will increase the energy absorption capacity of multi-cell structure. The additional number of tube cells contribute to the increases of the contact joint between each tube consequently this generate additional permanent plastic-hinges.

No abstract