Energy absorption efficiency of open-cell pure aluminum foams

For their application as crash absorber the specific energy absorption efficiency of metal foams is of particular interest. Current literature offers limited information about the relation between the relative density of open-cell foams and their specific energy absorption efficiency. With the aid of own measurements and literature data this relation was derived. According to the developed correlation a relative density of less than 3% can be suggested for a high specific energy absorption efficiency of open-cell ductile foams. To achieve an efficiency of at least 50% a relative density of 50-60% is suggested.