Experimental and numerical analysis of parameters affecting the mechanical behavior of closed cell aluminum foam in low-speed impact

In this paper, the parameters such as the diameter of the foam forming hollows, the thickness of the walls in the horizontal and vertical directions were investigated on the energy absorption of aluminum 356 closed cell foams produced by the lost foam casting method under low-speed impact. To reduce production costs and the number of tests, the test design method was used. Based on the design, 15 experiments were proposed. Then, according to the results of the experiment design, the simulation of the foams was done using Abaqus finite element software and based on the amount of absorption in different states, 4 foams were selected for the final production with two simple cubic structures and body center cubic. To perform the low-speed impact test, a 50 kg drop weight device that falls from a height of three meters was used. The results showed that the smaller the diameter of the foam holes, the higher the energy absorption. Also, the thickness of the foam walls in the horizontal direction has a greater effect on the energy absorption of the foam than in the vertical direction. Among the two types of structures studied, the simple cubic structure performed better than the body center cubic structure. Comparison of simulation and experimental results showed that the difference is between 10-30%. Most of this difference was related to the body center cubic structure feather, the main reason of which can be seen in the fact that it is more difficult to make these samples in reality compared to the ideal state of simulation.