Fraunhofer IWU showcases WEAM: wire-based functions integrated directly into 3D printing

At Formnext 2025, the Fraunhofer IWU is presenting the latest expansion stage of its Wire Encapsulating Additive Manufacturing (WEAM). The technology applies electrical functions to parts during or immediately after 3D printing and targets applications where sensing tasks, power and data transmission, as well as EMC shielding must be integrated into a mechanically robust structure. The trade show setup features a production-ready WEAM printhead integrated into a system from machine builder CR3D.

The core of the approach is the use of industrial standard wires and strands with homogeneous alloy and consistent cross-section. In the interplay of continuous tool rotation, freely selectable conductor layout, and a material-compatible encapsulation, electrical properties can be specifically defined via alloy, diameter, and geometry. This allows WEAM to address known limitations of paste-, ink-, and powder-based conductors, such as current-carrying capacity, ohmic losses, or cyclic loading. The institute demonstrates this, among other things, with radome heaters for automotive sensors: heating conductors are applied to a film, subsequently formed, and integrated into the component without delamination during overmolding. The locally generated heat prevents ice formation and reduces energy demand compared to conventional cabin heating.

Further exhibits show form-flexible conductors on 0.1 mm TPU film with crossing, electrically insulated traces, as well as PFAS-free high-temperature flex circuits. The latter are based on thermoplastic substrates and are suitable for use up to 260 °C, and briefly up to 300 °C. Because conductor and substrate are materially bonded, a robust, bend-resistant unit with a single-material construction is created, which facilitates repair and recycling.

For manufacturers in automotive, aerospace, mechanical engineering, or defense, WEAM opens a path to bring electrics and electronics closer to the structure and reduce wiring harnesses. Decisive for transfer to series production are now robust process windows, qualified surfaces, and test concepts that secure electrical function over the service life.