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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.

A detailed material testing was carried out before the conservation project of the János Arany statues of Garden of Hungarian National Museum. The scope of the testing to analyse the corrosion products on the surface and help to develop the best cleaning and protection practice. Samples were taken from more areas and the samples were analysed by SEM-EDS, XRD, FT-IR methods. This article introduces the results of the testing and the relevant effect to the conservation process.

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There are several methods to study the kinetics of the recrystallization process. DSC measurement is one of the most effective measurement methods. Cellular automata simulations are frequently used in computational studies. Both methods give and use kinetic constants. The aim of this study to find the relation between the kinetic constants. Additionally an evaluation method is introduced based on the DSC evaluation and cellular automaton which can compute a more detailed kinetic description of recrystallization.

In the aluminum industry providing good quality materials is of utmost importance. Recently, after surface roughness, surface color became a role-playing factor for the customer. Producers require measurable values for classifying the surface decolorization to settle an agreement between the factory and the customer during a complaint. In this study two sources of the surface decolorization are identified in the case of aluminum-magnesium alloy sheets. Based on the results an evaluation scheme is introduced, which analyses the color components of the reflected light from the aluminum-magnesium sheet surface.