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Hybrid components produced by two or more different process technologies grant the possibility to compensate the drawbacks of the used processes. The combination of additive manufacturing (AM) and forming offers geometrical freedom in extensions of geometrical simple parts in a cost-efficient way. Unlike the combination of bulk metal forming and AM, sheet metal forming and AM is less investigated. Especially for Ti-6Al-4V, which is widely used in AM but has a low formability at room temperature, research is still needed. In this study, the formability of hybrid parts made of Ti‑6Al‑V consisting of sheet material and additively manufactured elements (AME) is investigated for a hemispherical punch geometry. Thus, a designed tool for forming of hybrid parts at elevated temperatures is used. First investigations with a specially designed stretch forming tool demonstrate the distinct influence of the additively manufactured bodies on the stretch forming process of hybrid parts made of Ti‑6Al‑4V. Namely, the achievable drawing depth is reduced for hybrid parts as the functional elements are placed in the area of highest stresses, distorting material flow.

Hybrid parts with additively manufactured elements (AME) combine the advantages of two or more manufacturing processes, e.g., forming and additive manufacturing (AM), and thus offer a solution to the increasing demands of industrial trends such as personalized mass production. Despite their advantageous properties, research in this field still lacks in clear classification and process interactions. Due to the strong influence of the AME on the formability of hybrid parts, the combination of laser-based powder bed fusion (PBF-LB) with subsequent sheet metal forming is examined in this paper. Therefore, cylindrical functional elements are built up on sheet metal and the resulting hybrid components are subsequently formed. Common forming processes such as bending, stretch forming and deep drawing are compared in regard to the different stress states. The results show a reduction in formability for hybrid components compared to conventional sheet metal materials. Reasons found are geometrical properties, gradients of mechanical properties and induced stresses. Consequently, requirements for the additive manufacturing process regarding a subsequent forming process are outlined. Namely, the gradient of mechanical properties should be smoothened, residual stresses kept low and the design of AMEs should avoid stress concentration.