Comparison of Energy Absorptive Capacities of Different Aluminum Alloy Foams Placed Inside the Crash Box

Abstract

Increasing population worldwide and the resulting increasing number of automobiles increase the risk of traffic accidents. Due to this increasing risk, automobile manufacturers take various safety measures to protect drivers and passengers in case of possible accidents. Crash boxes are one of the passive safety system elements that are the first to absorb the impact in the event of a front or rear impact accident, absorbing the resulting deformation energy and ensuring that it is transmitted into the car at the least possible level. Therefore, increasing the energy absorption ability of crash boxes is an extremely important issue. In this study, it was aimed to increase the energy absorption capabilities by placing aluminum foam based materials produced by using the powder metallurgy method using three different aluminum alloys (Al2024, Al5083, and Al6061) inside the crash boxes, which are normally manufactured as hollow. In addition, the produced aluminum foams were compared in terms of pore sizes with SEM images. It can be said that Al6061 is the most ideal material among the alloys used in terms of pore structure and homogeneity. On the other hand, Al6061 alloys produced the greatest damped energy value within the parameters of the investigation, 221.711 J. This value was 169.556 J for Al2024 alloy and 214.101 J for Al5083 alloy. As a result, it was concluded that the amount of energy absorption can be increased by about 4-5 times by using metallic foams produced using aluminum materials compared to the empty crash box.