New Aluminum Syntactic Foam: Synthesis and Mechanical Characterization

Abstract

Metal matrix syntactic foams (MMSF) are advanced cellular materials constituted by a system of a minimum of two phases, in which a dispersion of hollow particles is embedded by a continuous metal matrix. The incorporation of porous fillers favors the development of low-density materials with exceptional behavior for damping vibrations, impacts, and blast effects, shielding acoustic, thermal, and electromagnetic energies. There are three main techniques to produce them: infiltration casting technique (ICT), stir casting technique (SCT), and powder metallurgy technique (P/M). The first two techniques are used for embedding filler into lower melting point metallic matrices than fillers, in contrast to P/M. The present study demonstrates the feasibility of producing MMSF with components of similar melting points by ICT. The fillers were synthesized in-situ with aluminum and a natural foaming agent from wastes of Spanish white marble quarries. These novel aluminum syntactic foams (ASF) were mechanically characterized following the ISO-13314 and exhibited a porosity, plateau stress, and energy absorption capacity of 41%, 37.65 MPa, 8.62 MJ/m3 (at 35% of densification), respectively. These properties are slightly superior to equal porosity LECA ASF, making these novel ASF suitable for the same applications as LECA-ASF.

Fabrication methods and property analysis of metal foams – a technical overview

“…The energy absorption capability of metal foam produced by four-layer deposition of SUS316L and titanium-hydride (TiH 2 ) powders together through the direct energy deposition method was 185 kJ [36] . Plateau stress and energy absorption capability of metal matrix syntactic foam produced by infiltration casting were 37.65 MPa, 8.62 MJ/m 3 at 35% of densification, respectively [88] . Compressive strengths of cast Al–Fe composite foam, PM processed low carbon steel, and stainless steel foam produced by steel hollow spheres were found to be 67, 76, and, 136 MPa, respectively, over 10−50% strain [136] .…”

“…can be easily foamed and predefined shape products can be prepared with the help of required mould geometry. Sánchez et al [88] Aluminium alloy Filler particles and Foaming agent was taken from wastes of Spanish white marble quarries.…”

Estimation of cutting forces in CNC slot-milling of low-cost clay reinforced syntactic metal foams by artificial neural network modeling

“…Al, Ti, Mg, Zn and Fe-based alloys are used as the matrix material of MSFs (Sánchez de la Muela et al ., 2022). However, Al is the most preferred material because it is easily castable, has high corrosion resistance and can be heat-treatable (Yavuz et al ., 2023).…”

Microstructure and Strengthening Effect of Coated Diamond Particles on the Porous Aluminum Composites

“…Several researchers reported the influence of metal additives and reinforcement on both the foaming as well as compressive behaviors of the resultant composites. The introduction of the alloying elements such as tin (Sn), boron (B), copper (Cu), magnesium (Mg) or chromium (Cr) into the Al matrix has been found to enhance the properties of porous composites [8][9][10][11][12]. The effects of the addition of boron carbide (B 4 C), silicon carbide (SiC), alumina (Al 2 O 3 ) and carbon nanotubes (CNTs) to Al or their alloys on the compressive properties have been extensively studied [13][14][15][16][17].…”