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Composite metal foams (CMFs) are hybrid structures, which are usually produced from separate parts, and not in one step as functional, structural elements. Functional CMFs are characterized by high strength, high stiffness, and extreme energy absorbing properties compared with conventional metallic foams, which allow them to be used as load‐bearing and energy absorbing elements. Test specimens are made in AlMgSi0.5 tubes with the wall thickness of 5 mm. AlSi12 casting alloy is used as matrix material. To ensure the foam structure porosity, lightweight expanded clay aggregate particles (LECAPs) are used with unimodal and bimodal size distribution. The results show that low‐cost unimodal and bimodal foam‐filled tubes (FFTs) can be produced in situ by inert gas pressure infiltration. Besides their low density, these CMFs achieve high strength, high toughness, and special, functional properties compared with simple metallic foams. After heat treatment, in situ produced bimodal FFTs have the highest energy absorption capacity of an average of 67.2 J cm−3, which is 9% higher than the average value of the ex situ FFTs. Therefore, it is advantageous to produce in situ FFTs, because with proper manufacturing, it requires less machining, making the production easier, while achieving better compressive properties.

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Metal matrix foams (MMFs) are mostly used in the automotive industry due to their high specific energy absorbing capacity and relatively low weight. During this research, bimodal metal matrix foams were produced, where the filler was ceramic hollow spheres (CHSs) made of high-purity alumina with the nominal diameters of Ød1 = 7 mm and Ød2 = 2.4 mm. The hollow spheres of different sizes were used in 1:1, 2:1 and 4:1 volume ratio, which after mixing can be considered as uniformly distributed. Al99.5 was infiltrated between the CHSs with low pressure to create a cellular material. The manufacturing parameters have a significant influence on the properties of the finished metal matrix foam. Different preheating temperatures, melt temperatures, infiltrating pressures and time was applied to achieve proper wetting and filling. Samples were evaluated based on macro images and microscopic photographs.

Tattooing is becoming more and more accepted at different levels of society today. A contributor to this is that besides body decoration, the cosmetics industry is increasingly using it for make-up tattoos and to hide skin imperfections and surgical scars. Tattoo needles, despite being in direct contact with human tissues and even with blood, are not subject to current Medical Device Regulation, so they do not require a number of material and biocompatibility tests in order to be placed on the market. The focus of our research was on how the needle and the soldering of the needles are damaged during tattooing, and how this develops over time, as a worn needle tip can not only degrade the quality of the tattoo, but also increase skin breakdown and the amount of dissolving allergenic substances.

A fémhabalapú kompozitok olyan hibrid szerkezetek, amelyek legfontosabb előnyei a kis sűrűség mellé társuló nagy fajlagos szilárdság és a mechanikaienergia-elnyelő képesség. Kutatásunk során EN AW-6060 anyagú, 50 mm átmérőjű és 5 mm falvastagságú csőbe helyezett, duzzasztott agyagkavics cellaképző ágyazatot infiltráltunk EN AC-44200 olvadékkal, így állítva elő szintaktikusfémhab-alapú kompozitot. A fémhabalapú kompozit gyártását kisnyomású infiltrálással végeztük az alumíniumcső nyomás alá helyezésével. Hat különböző mintát vizsgáltunk: szintaktikus fémhabot, csőben infiltrált, illetve utólag csőbe sajtolt, előtte adott méretűre esztergált szintaktikus fémhab tömböt, valamint ezek hőkezelésen átesett párját. A zömítővizsgálatok eredményei alapján a hőkezelés jól látható javulást hozott a fémhabalapú kompozitok nyomó igénybevétellel szembeni ellenállásában.

In everyday use glass materials cause a lot of damage or injuries when broken, as fracture mechanism and damage runoff can not be predicted precisely. To gain knowledge on this issue, we studied the properties of tempered glass. The glass test samples were exposed to two types of destructive evaluations: normal and high temperature three-point bending and room temperature dynamic experiments with colliding small steel spheres. The evaluation showed that high temperature experiments are in correlation with sharp fracture edges, and dynamic impact creates shell featured circular crack propagation which prevents the spreading of the radial cracks, so the damage is concentrated to a small area.