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Cold spraying has great potential for additive manufacturing, especially of oxidation-sensitive metals, because the material is not melted and significantly higher deposition rates can be achieved than with conventional additive manufacturing processes such as selective laser melting or direct metal deposition. Titanium is regarded as a high-performance engineering material due to its unique combination of properties, including good corrosion resistance, biocompatibility and high strength at comparatively low density. However, due to its high price, it appears reasonable for many applications to use material compounds in which titanium is only used on the surface of the workpiece, while less expensive materials such as aluminum are used for the remaining volume. In the present work, cold sprayed pure titanium coatings were deposited on Al substrates and then formed to defined 3-dimensional final contours by die forging and rotary swaging. Different porosities were selectively set in order to evaluate their influence on the coating adhesion and cohesion in the forming process. Pre-consolidation of the coatings and the use of Al/Ti interlayers proved to be promising strategies.

Additive Manufacturing is an established process group that includes various technologies. In contrast to subtractive methods, complex components can be produced by applying layers of construction materials. In accordance with the standard VDI Guideline 3405, additive manufacturing technologies can be differentiated into wire- and powder-based technologies. The basis for these experimental investigations is a Wire Arc Additive Manufacturing (WAAM) process with a high build-up rate (Cold Metal Transfer - CMT) to produce a rectangular thin-walled component made of G4Si1 (1.5130). In order to analyze the influence of a subsequent forming process on the microstructural properties and the forming behavior of the components, compression tests were carried out. Therefore, cylindrical specimens were made out of the additively manufactured components by machining. To be able to take a possible anisotropy in the workpiece caused by the multi-layer welding into account, the samples were taken both along and across the welding direction. To evaluate the inhomogeneous component properties, cast specimens with a representative microstructure were produced by inductive melting of the filler material and subsequent a solidification with an appropriate cooling rate. In addition to the cold forming of the additively manufactured components, the investigation also includes hot forming and the influence of a corresponding heat treatment. The experimental examination was completed by the analysis of the microstructure of each material state. The aim of the research work was to prove the homogenization and optimization of the mechanical properties of additive manufactured components due to a subsequent forming process.

Wire-arc additive manufacturing (WAAM) complex components can be built-up layer by layer from metallic construction materials. In this investigation two different WAAM processes with high built-up rates (CMT and pulsed GMAW) were compared in terms of geometry formation and component properties. The reference is a rectangular thin-walled geometry made of the austenitic stainless steel 316LSi (1.4430). During the welding process, the temperature development in the weld layer was measured. The experimental comparison of CMT (\({\text{R}}_{\text{m}}=630 {\text{MPa}}\)) and pulsed GMAW (\({\text{R}}_{\text{m}}=605 {\text{MPa}}\)) is completed by the determination of the mechanical properties using micro-tensile tests. Furthermore, the additive-manufactured walls were cold rolled with a subsequent heat treatment or hot rolled to provide proof of formability and forming induced property improvement.