3D‐printing with steel on thin sheets for application in free form façade construction: welding process development and material properties

Wire and Arc Additive Manufacturing (WAAM) became a significant research field in structural engineering over the past years. It offers the opportunity to apply material fast and precisely, following the load path, inducing effective material consumption. Considering free‐formed sheet‐metal façades, to date large thicknesses are necessary to maintain the final shape and load‐bearing capacity that however causes high material consumption and costs during the construction processes. Hence, WAAM could be an opportunity to reduce the amount of mild steel used for free‐form façades. As part of a research project at TU Darmstadt, 1 mm thick free‐form sheet‐metal façades elements have been manufactured using WAAM. Due to precisely welded lattice structures, placed on the backside of the metal sheet, the reinforcement will be ensured. Wide studies on welding parameters focused on a stable process without damaging the later frontside of the façade panel and on process optimization. In addition, material properties of the welding material have been determined to check its usability in façade construction

Open-Source TIG-Based Metal 3D-Printing

Metal 3-D printing has been relegated to high-cost proprietary high-resolution systems and low-resolution low-cost metal inert gas (MIG) systems. In order to provide a path to high-resolution, low-cost, metal 3-D printing, this manuscript proposes a new open source metal 3-D printer design based around a low-cost tungsten inert gas (TIG) welder coupled to a commercial open source self replicating rapid prototyper. Optimal printing parameters for the machine are acquired using a novel computational intelligence software. TIG has many advantages over MIG, such as having a low heat input, clean beads, and the potential for both high-resolution prints as well as insitu alloying of complex geometries. The design can be adapted to most RepRap-class systems and has a basic yet powerful free and open source software (FOSS) package for the characterization of the 3-D printer. This system can be used for fabricating custom metal scientific components and tools, near net-shape structural metal component rapid prototyping, adapting and depositing on existing metal structures, and is deployable for in-field prototyping for appropriate technology applications