Microscale testing of the strut in open cell aluminum foams

Abstract

This paper presents the results of micro-tensile testing of the individual struts that were extracted from open cell aluminum foams in the as-fabricated (F), annealed (O) and T6-strengthened (T6) conditions. The results reveal that foam struts are generally stronger and more dutile than the corresponding solid alloys under the same heat treatment conditions. The distinguished strut properties are attributed to the unique grain structures of the struts typically consisting of one grain or having bamboo-like grain structure. The measured strut strengths are also incorporated into mechanics models to estimate foam strengths. A comparison of the predicted and measured foam strengths shows that direct measurement of strut properties is critical to make precise estimation of foam strengths.