Low Velocity Penetration Mechanical Behaviors of Aluminum Foam Sandwich Plates at Elevated Temperature

This paper presents the low-velocity impact tests on the sandwich plates with aluminum foam core and aluminum skins at elevated temperatures. A furnace, attached to an Instron Dynatup 9250 HV drop hammer system, was designed to accomplish the penetration tests at temperatures up to 500°C. In order to process the experimental data accurately, the numerical vibration analysis was conducted to determine the threshold frequencies of the fast Fourier transform (FFT) filter for the original impact data. The experimental results showed that the failure modes of the sandwich, peak load and absorbed energy varied obviously with temperatures. Furthermore, the results showed that the failure modes of the top skin and metal foam core showed minor changes with respect to temperatures. Whereas the failure mode of the bottom skin and peak loads changed significantly with respect to temperatures. Also, the absorbed energy revealed a three-stage variation with the change of temperature.