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Cellular metals based on iron have been intensively investigated during the last two decades. Because of the significant decrease in of the structural density of iron based cellular structures, numerous technologies have been developed for their manufacturing. Besides the tremendous weight reduction a combination with other properties like energy and noise absorption, heat insulation and mechanical damping can be achieved. This contribution will give an overview about the latest state in iron based cellular materials, including technologies in manufacturing, properties and potential applications.

Potential candidates for thin-film diffusion soldering were investigated by analysis of phase formation and measurements of mechanical and thermal stability of thin-film bonds. Bilayers of Pt/In, Pd/In, and Zr/Sn of 500 nm/500 nm thickness were prepared by direct current magnetron sputtering followed by a 5 nm, thin protective Au layer. Single bilayer samples were heat-treated between 200°C and 500°C for 3-30 min and studied by x-ray diffraction (XRD) analysis. Some bilayers were bonded face-to-face between 300°C and 500°C for 3-30 min and sheared-off either in shear-strength measurements at room temperature or in remelting experiments up to 1,100°C. Phase formation in Pd/In and Pt/In thin films is much faster than in Zr/Sn thin films. An interaction of Au in addition to a questionable thermal stability of PtIn 2 complicated the reaction in Pt/In samples. A revised partial Pd-In phase diagram was constructed, correcting the compound 'PdIn 3 ' to Pd 3 In 7 . The Pt/In and Pd/In thinfilm systems are very promising candidates for thin-film diffusion soldering.

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Magnesium alloys offer excellent properties with regard to application as degradable implant. For bone implants, it is often desirable to use porous materials. However, the preparation of high-porosity magnesium implants has been difficult so far. The present study uses melt extracted magnesium fibers as the starting material for the sintering of highly porous magnesium bodies, i.e., from alloys MgY4 (W4) and MgY2Zn1CaMn (WZ21). Single short fibers of these alloys with an equivalent diameter between 100 and 250 mm and a length of 4-8 mm are manufactured by melt extraction. Thermodynamic calculations are used to determine the best conditions for liquid phase sintering of these Mg alloys. As no organic or other substances are needed in the process, it is possible to obtain high-purity, high-porosity (up to 75%) bodies with exclusively open porosity. Metallographic studies as well as mechanical and corrosion testing experiments complete this work.