Delamination resistance enhancement for metal laminated panel under the effect of constant cyclic load

This paper presents the testing of a metal laminated panel with two main dimple core configurations under a four-point bending setup. The cavity features on the core layer led to unstable bonding strength. An alternative core design must be proposed to improve delamination resistance in panels as this plays a significant role in retaining their structural integrity. Specimens with AR500 steel outer skins and a magnesium alloy AZ31B main core were tested under constant cyclic loading conditions. The 50% and 70% of maximum cyclic flexural loading were given to the specimens at frequencies of 10Hz. The tested specimens were cut into the cross-sections and the bonding regions were examined under microscope. The results showed that the dimple core configuration with diameters of 6.0 mm and depths of 3.0 mm exhibited better delamination resistance, which improved for this configuration by between 31% to 38% compared to the larger dimple configurations. The data survivability indicated a good correlation between the experimental and simulated data as the data lay within the 90% confidence intervals. In conclusion, a newly designed dimple configuration for laminated panels demonstrated improved delamination resistance.