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The application of coatings to structures is generally done in order to locally tailor properties. For this purpose, powder-based laser metal deposition (LMD) can be utilized. The resulting properties of the coatings are not only affected by the LMD process parameters, but also by the substrate material. In this regard, the chemical composition as well as its initial microstructure of the substrate has a significant influence. In the present study two Al-Cu alloy substrates, 2139 and 2198, are used for the LMD of pure Al powder. The resulting coatings possess clearly different properties, although the same process parameters are used.

Powder-based laser metal deposition (LMD) of Ti alloys enables the manufacturing of geometrical complex structures with tailored properties for high-temperature applications. The most important parameters for the LMD-process are the laser power, process velocity, laser focus position, gas flow and powder feed rate. Compared to the predominantly used Ti-6Al-4V, Ti-6Al-2Sn-4Zr-2Mo shows a higher oxidation resistance and a lower creep rate. For determining suitable process conditions, a parameter study using Ti-6Al-2Sn-4Zr-2Mo powder is performed. Subsequent, the parameter transfer to a γ-TiAl alloy is examined. The assessment of the dissimilar-LMD-structures is conducted by visual inspection, radiography inspection, microstructural analysis and hardness measurements.

Laser beam welding of similar and dissimilar joints made of 7075-T6 and 5182-O sheets is conducted. A new approach of the Helmholtz-Zentrum Geesthacht is used to solve the problems of weldability and softening. The microstructural characteristics and the mechanical properties of the joints are evaluated. With this information it is possible to initially assess the formability of the tailored blanks. Finally the formability of the welds will be validated via a sheet metal forming process. Owing to the good formability of the base materials, the results obtained for the welded joints are compared with base material properties.