Laser additive manufacturing processes are used for the production of highly complex geometric structures due to their high geometric freedom. Additive manufacturing processes, in particular powder-based selective laser melting, are used to produce metallic additive manufactured components for the automotive and aerospace industries. Different materials are often joined together to realize sustainable lightweight construction. The production of such mixed construction joints is often realized using mechanical joining technology (e.g. self-piercing riveting). However, there is currently very little experience with the mechanical joining of metallic additive manufacturing components. Furthermore, there is insufficient knowledge about the effects that occur during the mechanical joining of additive manufacturing components. In this article, a method is presented to investigate the joinability of additively manufactured components with conventionally manufactured components using a numerical simulation of the self-piercing riveting process. For this purpose, the additive manufacturing materials are characterized experimentally, the simulation model is configured, and the joining process with additive manufacturing materials is represented in the numerical simulation. Furthermore, the influence of the building direction on the mechanical properties is shown using miniature tensile specimens. Besides the configuration of the simulation model, the influence of heat treatment on the self-piercing riveting process is presented.

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Die Herstellung von Blechbauteilen umfasst mehrere Schneid- und Umformoperationen, welche die resultierenden Bauteileigenschaften beeinflussen. Daher weichen die Eigenschaften vom Ausgangszustand des Halbzeugs ab, was bei der Auslegung von Clinchverbindungen berücksichtigt werden muss. Durch die Vernetzung der Einzelverfahren auf Basis der Prozessdaten werden ein Vorgehen zur Ermittlung der Halbzeugeigenschaften beim Scherschneiden und die Auswirkungen auf die Verbindungsqualität beim Clinchen aufgezeigt.   Sheet metal components are manufactured in various cutting and forming operations influencing the resulting properties of the parts. As these properties differ from the initial state of the semi-finished products, they have to be considered in the design of clinched joints. By connecting individual processes, this paper presents an approach for determining the properties of semi-finished parts in shear-cutting operations as well as their effects on the joint quality in clinching.

Due to their excellent mechanical properties, fiber-reinforced plastics are increasingly being used in technical lightweight products. The multi-material design of fiber-reinforced plastic and metal leads to great lightweight constructions because the potential of the materials can be efficiently used for the specific field of application. This restricts conventional thermal joining technologies and shows the demand for cost-effective and efficient mechanical and adhesive joining technologies. This paper depicts the development of a new type of auxiliary joining element with integrated pin structures whose purpose is to increase the load-bearing capacity of mechanically joined fiber-reinforced plastic/metal combinations. In addition, the hole area of the fiber-reinforced plastic can be relieved in this way by transferring the operating loads into the laminate via the pin structures. In addition to experimental studies of the application methodology, the quasi-static and dynamic load-bearing capacity will be investigated. This paper presents detailed information about the development of the new auxiliary joining element and the characteristics of the joints, including corrosion effects generated by a corrosion camber.

The process chain for the manufacturing of sheet metal components in mass production includes various cutting and forming operations, which influence the resulting properties of the parts and therefore subsequent manufacturing steps, such as clamping and joining. It is shown that clamping of the components leads to superimposed residual stresses and geometry changes. Therefore, the part properties differ from the initial state of the semifinished products, which has to be considered in the design of clinched joints. This paper presents an approach for coupled determination of the properties of semifinished and finished parts during deep drawing and clamping as well as their effects on the joint quality during clinching. One method for the effective and efficient determination of the properties of semifinished products and components during production is using process data from the preceding manufacturing processes, which is concretely presented in this work. In addition to the interconnection of the entire production chain, it is necessary to define relevant process data for each individual manufacturing step and to correlate the data with the material properties reliably. Therefore, the cross-process interactions of different steps of the process chain for the manufacturing of sheet metal components and the effect of process variations on subsequent manufacturing steps are investigated. Consequently, the boundary conditions for a mechanical joining process based on data from preceding process steps can be predicted.