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During the last ten years, the subgroup of functional materials, foams are coming forth with their combined features such as light weight, hgh specific strength, large surface area and high absorbing capabilities. These structures consist of two branches: open cell foams with enormous surface area enabling fluids to flow through and closed cell foams having the ability of absorbing various kinds of energies (sound energy, impact energy, magnetic energy, vibration energy, radiation). Closed cell aluminum foams are largely investigated metal foams because of base metal's advantages like low density, low melting point, low cost, recyclability and being incorporated by several kind of alloys. As for the closed cell aluminum, pores have to be generated usually by gases, either introducing the gas into the melt or creating a gas pressure inside the semimolten compact. The latter is also referred as powder route production, where metallic hydrides or carbonates act as foaming agents releasing gases into the compressed precursor by decomposing in certain temperatures. In literature, mostly titanium hydride (TiH2) is preferred as the foaming agent due to its high decomposition temperature. Also heat treating to titanium hydride can even delay the decomposition temperature. Thus, it enables proper foaming without cracks. As the nature of the structural material, 6000 series alloys are of special interest due to their heat treatable nature and positive effects on foaming. In this research, three factors, Mg, Si and TiH2 at three levels are examined according to the designed experimental plan. The three levels of Mg and Si are 0.5-1-1.5% (wt) and 0.4-0.6-0.8% (wt) for TiH2. Response surface methodology is used to analyse the effects of these factors on foaming and these effects are demonstrated on the selected response: micro hardness. The aim of this work is to evaluate the effects of the factors determined in the designed experimental plan and to realize the alloying during foaming. In the total of 16 experiments, powder compositions are varied while the other conditions are held constant for the sake of meaningfullness of the results. Briefly, each powder composition are weighed as accurate as possible with a high precision balance that can recognize 0.0001th of a gram, then mixed separately for half an hour and finally they are compacted with uniaxial press to get the closest theoretical density value (least 99.5% is reached for any precursor is achieved). The theoretical density of the precursior's are tested by Archimedes' Principle. Lastly, precursors are foamed in an atmospheric furnace at 715° for 12 minutes. Then the foaming mold is placed on a copper plate which is continuosly cooled with water to solidify the all body as soon as possible. The so called importance of theoretical density comes from the necessity of imprisoning the foaming gas within the precursor. It is important when the released gas is H2 with low molecular diameter which can easily escape from any cracks or holes. Also the decomposition temperature of TiH2 (∼400°C) when compared to metal's melting point (∼660°C) can cause release of the gas which is an issue because the decomposition takes place in solid phase makes difficult to keep the gas inside the precursor. Another point to be stressed in this study is alloying that is expected to happen during the foaming process without applying any prealloying procedure. To investigate that, responces are analysed with statistical tools and microstructure of the foams are investigated. Produced aluminum foams are cut into half to obtain micrographs with optical microscope (OM) and scanning electron microscope (SEM), and also to run microhardness tests. Statistical analysis (ANOVA and Regression) show quite good correlations (R2 and R2 adjusted being 89.3% and 86.28%) between mesaured microhardness values and calculated ones. It is found that silicon has a parabolic effect on microhardness where magnesium rises the hardness in a linear manner. 1.5 % Mg and 1.5% Si is the foam that gives the hardest composition. As expected, the foaming agent, TiH2, does not show significant effect on the microhardness. Microstructural characterizations show that powders are sintered and formed grains. And, plate like β-AlFeSi phases have formed at the grain boundaries. No Mg2Si phase is detected since the foams underwent no heat treatment procedure. Consequently, all these statistical and microstructural analysis reveals that alloying during foaming is achieved in the coherence with literature. [ABSTRACT FROM AUTHOR]