Some workpieces cannot be manufactured well using conventional methods such as casting. In such cases, an additive manufacturing process, such as build-up welding, is a good option. Optimizing this process is the aim of the EWA project, short for "Development of carbon-martensitic tool steels for the additive manufacturing of highly stressed forming tools using wire-arc additive manufacturing".
The starting materials are thin, powder-filled wires. They are additively processed into punching and forming tools. The project at the Chair of Materials Engineering at Ruhr-Universität Bochum, headed by Prof. Dr. Sebastian Weber, is funded by the Central Innovation Programme for SMEs of the Federal Ministry for Economic Affairs and Climate Protection and was launched on 22 June 2023. Wire-Arc Additive Manufacturing (WAAM) is largely based on gas metal arc welding. The starting materials are inexpensive metal wires.
In the EWA project, so-called cored wires are used: tubes filled with metal powder. These allow a high degree of flexibility in the alloy composition produced directly in the cored wire. As the material in the WAAM process is only applied locally according to a 3D CAD model where it should remain, 90-100% of the material applied in the process can be retained right through to the finished workpiece. This high degree of utilization means significant material savings and therefore an improvedCO2 balance compared to the conventional casting process route. And the process is fast: up to twelve kilograms of material can be applied within one hour.
