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Zinc has gained interest as a biodegradable material due to its adequate degradation behavior under physiological conditions and acceptable biocompatibility. However, during the use of zinc as a degradable orthopedical implant, the mechanical properties are expected to change while the implant needs to maintain its function and mechanical support for 12–24 months with the load gradually transferred from the degrading implant to the healing bone. For such investigation, six different kinds of open‐cell zinc foams are fabricated by a modified investment casting method displaying different pore densities and strut thicknesses. Compressive properties and corrosion behavior in simulated body fluids are studied to determine the map of the most relevant parameters that influence the degradation properties. After 4 weeks of immersion in Hank's solution, changes in the slope in the "plateau" region and strain localization are observed. These changes can be explained by supposing microcrack propagation into the depth of the struts due to the progressing corrosion attack. [ABSTRACT FROM AUTHOR]

For composite metal foam structures to be used as load‐bearing and energy‐absorbing elements, comprehensive testing should be done. Therefore, an extensive characterization of foam‐filled structures by various load types, such as axial and lateral compression, as well as three‐point bending, is carried out, aiming to differentiate the behavior of various cross‐sectional geometry foam‐filled hollow sections and the application of a tough epoxy adhesive and a ductile polysiloxane adhesive. Applying the epoxy adhesive improves the overall energy absorption by 10% during axial compression compared to the sum of the foam and empty hollow section. The application of the polysiloxane adhesive over the epoxy one increases the deflection at failure during three‐point bending by an average of 58%. The deformation and strength during axial compression and three‐point bending are hollow section dominated, while the foam core dominates the deformation and the strength during lateral compression for both produce composite foam‐filled hollow sections with epoxy and polysiloxane adhesive bonding. [ABSTRACT FROM AUTHOR]

In each industry, compromises have to be made when choosing materials. Lower-density materials have a significant advantage in the automotive sector, especially due to rising fuel prices, since weight reduction can lower overall fuel consumption. The advantageous properties of metal foams, such as low density, high specific strength, and excellent energy absorption, should be researched and exploited in as many areas and ways as possible. This research aims to perform and evaluate the bending tests of ex situ functional metal foams: aluminum alloy matrix (AlSi7Mg) was used, which was filled with Ø2.5-3.0 mm lightweight expanded clay aggregate particles and surrounded by thin-walled aluminum tubes (AlMgSi0.5) with a wall thickness of 2 mm and an outer diameter of Ø32 mm. Empty tubes, foam-filled tubes (with and without structural epoxy adhesive) and metal matrix syntactic foams were compared based on their flexural strength and energy absorption capacity. Quasi-static three-point bend tests were carried out up to 25 mm deflection. The foam-filled tubes with epoxy adhesive showed an average of 6% increase in flexural strength compared to the foam-filled tubes without adhesive and a 145% increase compared to the metal matrix syntactic foams. [ABSTRACT FROM AUTHOR]

Metallic foams are designed to be generally used by the transportation industry as energy‐absorbing reinforcements in bumper panels or as permanent cores for weight reduction. In composite metal foams (CMFs), the second phase is usually formed by hollow spheres or closed‐wall porous materials responsible for the gas (void) intake. Herein, three types of samples are compared: CMFs with unimodal small, unimodal large, and bimodally mixed small and large ceramic hollow spheres. Unmodified AlSi12 or Sr modified AlSi12 alloy is infiltrated between the spheres with low‐pressure infiltration to form the cellular structure. The effect of Sr modification on the matrix material properties and the matrix–filler interface layer is investigated. The samples are evaluated and compared based on microstructural analysis and standardized compressive tests; the fracture mechanism of the structure is analyzed using computed tomography measurements at different deformation states. The aim of this research is to develop high‐performance unimodal and bimodal CMFs, which have better specific mechanical properties than conventional metal foams, and to investigate the effect of Sr modification on the material properties. With these foams, additional weight reduction and higher energy absorption can be achieved, primarily used as automotive components. [ABSTRACT FROM AUTHOR]