Production of syntactic metal foams reinforced in the matrix material

Abstract

Abstract Metal foams are cellular materials where the matrix material is metallic, and gaseous cells are present in this enclosing material. Due to these cells, metal foams are low-density materials and have good energy-absorbing properties to their structure. Reinforcing materials can highly increase the load capacity of the structure. Our goal is to produce a low-cost, reinforced syntactic metal foam with an easy production process. The mechanical properties of A356 (AlSi7Mg) aluminium matrix syntactic foams are investigated, produced with lightweight expanded clay aggregate particles (LECAPs) as filler material and reinforced with aluminum-oxide (Al2O3) with a diameter of 1 mm and 0.5 mm, and silicon carbide (SiC) with a diameter of 0.4 mm in the matrix. 20 wt.% of the reinforcement was used in each case. The foams were produced by low-pressure infiltration, and the specimens, which were cut by conventional machining methods, were subjected to heat treatment. The grain structures of the materials were studied via optical microscopy, their mechanical properties were tested with compression tests. Results show that the production is successful, and reinforcement can be achieved with these materials.