, has conducted research on the technology of metallic composites, focusing on composite aluminium foams stabilized with ceramic particles. One technology which enables efficient, inexpensive and diversified -in terms of foam structure -control of foam properties is the foundry technology consisting in gas injection into liquid metal. This method requires precise control of the process parameters, especially regarding temperature stabilization, as well as precise injection of the gas into the metal. The process of foaming of liquid aluminium or its silicon alloys can also be conducted using ceramic particles. This is a metallic-ceramic composite foaming process (patent PL 211439 B1). The paper presents the process of structure forming of metallic-ceramic foams.Keywords: quality features, casting, metal matrix composites W Zakładzie Inżynierii Materiałów Okrętowych Akademii Morskiej w Szczecinie prowadzono badania nad technologią kompozytów metalowych, a w szczególności kompozytowych pian aluminiowych stabilizowanych cząstkami ceramicznymi. Technologią pian pozwalającą na wydajne, tanie a także elastyczne, w zakresie zróżnicowania budowy pian, sterowanie ich właściwościami, jest technologia odlewnicza polegająca na wdmuchiwaniu gazu do ciekłego metalu. Metoda ta wymaga precyzyjnego sterowania parametrami procesu, zwłaszcza w zakresie utrzymania i stabilizacji temperatury, a także precyzyjnego wprowadzania gazu do metalu. Proces spieniania ciekłego aluminium lub jego stopów z krzemem można przeprowadzać także z użyciem cząstek ceramicznych, czyli stosować proces spieniania kompozytu metalowo-ceramicznego (opatentowany PL 211439 B1). W pracy tej opisano proces tworzenia struktury pian metalowo-ceramicznych.

Authors of the paper present structures of composite metallic-ceramic foams (Al11SiC) of characteristic internal composition, produced at Maritime University of Szczecin. Diversification of pore size and structure of composite walls is present. The foams are manufactured by injection of a gas into a liquid composite using a special device, which allows to realize the foam manufacturing process in a continuous manner. This device also allows to control the parameters of the foaming process, which results in possibility of influencing, among other things, the size and the size distribution of formed gas bubbles. After manufacturing foams with both homogeneous and diversified gas pores, basic mechanical properties of these foams were examined, revealing a connection with their structure. Possibilities of applied research methods, utilizing a microscope and a tomograph, were also presented. Methods using computer image analysis were selected for the structure description.

When selecting the materials used in transport, in addition to the set of strength properties, which form the basis of the structural calculations, the possibility of weight reduction and the limitation of fire risks and maintenance activities should also be taken into account. The article provides a short description of both metal and metal-ceramic foams, as well as studies on multilayer sandwich composite materials. They consist of polyester-glass laminates and composite-ceramic foams. These materials were subjected to a technological three-point bending test. Such materials can replace the polyester-glass laminates that are commonly used in maritime transport and other industries.

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Problems of aluminum foam solderingProblemy lutowania pian aluminiowych StreszczenieKomórkowa struktura i wyjątkowe cechy pian aluminiowych są przyczyną problemów z ich lutowaniem. W artykule przedstawiono metody wytwarzania, strukturę, właściwości i zastosowanie pian aluminiowych. Scharakteryzowano również sposoby cięcia pian wodą, laserem i obróbką elektroerozyjną, jako metod przygotowania brzegów do lutowania oraz techniki łączenia pian: mechanicznych i spawalniczych ze szczególnym naciskiem na ich lutowanie miękkie i twarde. Określono ograniczenia i możli-wości lutowania pian aluminiowych. Słowa kluczowe: aluminium, piana metalowa, lutowanie AbstractThe cellular structure and unique properties of aluminum foams cause problems with their cutting and bonding. This paper describes the production methods, structure, properties and application of aluminum foams. It also discusses foam cutting methods such as water jet, laser and electrical discharge machining as means of edge preparing for brazing and soldering. Among methods of foam mechanical and weld joining, particular focus is put on brazing and soldering techniques. The limitations and possibilities of aluminum foam brazing and soldering are characterised.