In the aerospace industry there is a desire for a technical mature, additive manufacturing process for the production of large metallic structural components with low wall thickness. In addition to the newly acquired design freedom, which is a general advantage of additive manufacturing processes, the reduced tooling and production costs compared to today's manufacturing processes are essential improvements.
When 3D printing large-volume components, the 3DMP process developed by the Berlin machine manufacturer Gefertec offers particularly high deposition rates and thus the process has a high potential for establishment as a key technology. In order to qualify the process for an industrial application, research work on an arc-based 3D printing machine takes place at the BIAS Bremer Institut für angewandte Strahltechnik GmbH as part of the joint project REGIS. The Gefertec arc403 was commissioned on 26.06.2018 (Fig. 1) and, with a construction volume of 0.46 m³, is the largest metal 3D printer in the area of Bremen.
Figure 1: Handover of the GEFERTEC arc403 with project partners of the project REGIS, Photo: Airbus
REGIS is a collaborative project that brings together different partners from the aerospace industry, machine manufacturers and other research institutions. The aim of the project is to ensure homogeneous material properties in the production of titanium and aluminum using the 3DMP process. This is an important contribution to the removal of the geometrical constraints when manufacturing 3D printed components. The 3DMP process is an arc-based additive manufacturing process. Using CAD software, components are designed and then sliced into individual digital print layers, so-called CAM models. Based on the CAM models, a near-net shape semi-finished product is built up in layers using a metal inert gas welding process. After printing, the component is 3D-scanned. Based on the surface measurement data, the component is milled to the desired dimensions of the finished product (Fig. 2). The advantages of the process are manifold.
- Short process times due to high deposition rates and fewer production steps
- Production of large-volume components without limitation neither by a vacuum chamber nor a shielding gas chamber
- High cost-effectiveness due to the use of inexpensive wire as the base material, high material utilization and low tooling costs
Figure 2: Process chain of the 3DMP process
BIAS develops process monitoring. In order to be able to guarantee consistently homogeneous material properties, the focus of the work at BIAS is the investigation of the influence of heat input and shielding gas concept on the mechanical properties of titanium and aluminum components. Another focus is on developing an online process monitoring of the temperature of the printed material. For this purpose, the emissions-compensated, surface-resolved temperature field measurement developed especially at BIAS will be integrated into the machine concept.
The BIAS - Bremer Institut für angewandte Strahltechnik GmbH in Bremen, Germany develops new laser-based production technologies, systems and processes in the business areas "Material Processing and Processing Systems" as well as "Optical Measurement and Optoelectronic Systems". The BIAS is located in the Technology Park at the University of Bremen and cooperates closely with partners from the industry as well as national and international research institutions.
Excellent partners. The REGIS joint project is funded by the Federal Republic of Germany.The donor is the Federal Ministry for Economic Affairs and Energy on the basis of a decision of the German Bundestag (funding number: 20W1708F). Special thanks to the Federal Ministry for Economic Affairs and Energy and the project partners in the REGIS project.
Adding up in Aachen - Matthew Dale reports from the International Laser Technology Congress, AKL, where the potential for using additive manufacturing in series production was discussed