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Mit der Entwicklung von neuartig gefügten, dünnwandigen und damit leichten Bauteilen soll der ressourceneffiziente Einsatz von ultrahochfestem faserverstärkten Feinkornbeton in Tragwerken ermöglicht werden. Die Herstellung von modularen, leistungsfähigen UHPFRC‐Bauteilen wird durch den „Digital Workflow” aus digitaler Planung, Berechnung und CNC‐gesteuerter Fertigungstechnik ermöglicht. Durch die Verbindung von leichten Betonelementen mittels neuer hochpräziser Non‐Standard‐Fügeprinzipien können diese material‐ und kraftflussgerecht miteinander verbunden werden. Die Ergebnisse trocken gefügter Plattenbalken zeigen die Herstellbarkeit und das Potenzial der Trockenstoßverbindungen im realen Maßstab. Beim Nachweis der Tragfähigkeit von dünnwandigen Bauelementen zeigt sich, dass der Einfluss der Faserbewehrung zusätzlich beachtet werden muss.

Friction Press Joining (FPJ) is a suitable method for producing composites of aluminum and thermoplastics in lap joint configuration, which is based on modified Friction Stir Welding (FSW). During the joining process, a rotating cylindrical tool is pressed onto an aluminum surface. The resulting friction generates heat that is conducted to the bonding zone, leading to localized softening of the thermoplastics. In combination with the tool’s axial force and a suitable pre-treatment of the aluminum surface, a resilient composite compound is created. This paper presents the results of a surface pre-treatment of aluminum using laserradiation. The textures are essential for a strong connection, as they can significantly influence effective joining mechanisms, such as microscopic and macroscopic form fit. The experiments were carried out using different surface treatments by means of a single-mode laser for joints of aluminum (EN AW-6082 T6) and glass fiber reinforced polyamide (PA6 GF15). The aim of the study was an increased understanding of process behavior and joining mechanisms. The shear strength could be increased by 40 % compared to previous studies with the presented laser surface treatment.

Composite extruded, unidirectionally spring steel wire reinforced profiles have great potential for lightweight applications. Joining of these profiles represents a difficult challenge due to the different material properties, which eliminate fusion welding as a possible joining method. Friction stir welding (FSW) has recently been used to join these profiles, the disadvantage of which is that the reinforcement elements may be bent and fragmented during welding leading to drastically reduced mechanical properties compared to non-joined profiles and even to the unreinforced matrix material. In order to minimize the disturbing influences of the reinforcement elements on the joining strength, the weld axis was shifted to the retreating side, reducing wire-pin contact at the advancing side. As a second remedial measure an insert made of matrix material was placed between the joining partners before joining in order to reduce the contact on both sides. In-situ tensile tests within an X-ray micro computed tomograph (µCT) showed that shifting the weld axis could not improve the joint quality significantly. However, the use of an insert improves the offset yield strength (Rp0.2) by about 50 %.