Last year, Airbus began an ambitious project with UK supplier GKN to flight-qualify a 3D printed titanium structural bracket for its A320 aircraft (www.machinery.co.uk/110930). Doing so uses far less valuable titanium compared to milling the parts from plate, and is quicker because no moulds need to be made. Parts made by additive manufacturing using Arcam (01926 491300) powder-bed technology have been found to perform as well, or even better, in terms of fatigue life, after post-processing.
Much of that project is concerned with changes involved in scaling up production by a factor of 20 or more to achieve production volumes required. This is essentially a matter of quality assurance: ensuring that the process offers adequate reproducibility and repeatability. Airbus is also broadcasting what it is learning to its design engineers, to instruct them how AM can be used to make new kinds of aerospace parts.
The company’s goal is to print one tonne of metal powder a month in 2018, according to Airbus’s head of emerging technologies and concepts, Peter Sander.
Airbus is also involved in research that has a production aim as its target in Germany. Here the company has helped set up a German research centre for additive manufacturing processes with a focus on aerospace at the Munich technology institute Ludwig Bölkow Campus.
As part of this project, Airbus Group Innovations, Airbus Safran Launchers and Airbus subsidiary APWorks signed a declaration of intent in April with 3D printer manufacturer EOS (01926 623107), engine manufacturer MTU Aero Engines, the Institute for Machine Tools at the Technical University of Munich, Fraunhofer IIS, the University of Bremen and prototyping specialist ESI Group.
PROPULSION PARTS FOCUS
The new centre, called Aerospace Factory Additive Manufacturing, will run research and development projects on propulsion components and work to train and safeguard the next generation of skilled workers. Cooperation partners will also be teaming up in a project centre with a pilot factory. A priority is to take the research results from the test environment and apply them in industrial production.
Research topics covered extend along all of the AM value chain: component design; powder production; the additive manufacturing process, including process simulation and post-processing, along with quality control of the process and components. Researchers will also investigate tailor-making materials for the 3D printing process.
The Aerospace Factory is financed by industry, as well as national and international research and development contracts: the latter include, for example, the German space administration and the European Space Agency, according to EOS.
Also looking at AM in the round is a wholly private sector collaborative project in AM for aerospace that has been set up by US simulation software company Altair (01926 468600), AM company Morf3D and Swiss space technology component manufacturer Ruag. This will similarly address every aspect of the AM process, including design, analysis, build, test and certification, out of a desire to offer AM services to aerospace, including space, propulsion, aircraft interior and airframe applications.
Within the group, Altair will bring design and analysis software (its solidThinking Inspire product); Morf3d will lead program management, part production, R&D and associated quality control; and Ruag will be in charge of design, analysis, documentation, testing and certification. The team will call upon the AM facility at Morf3D’s Innovation Centre (in California), which includes various direct metal laser sintering machines, and Ruag’s test facilities.
Says Dr Robert Yancey, VP of aerospace at Altair Engineering: “There is clearly a need for resources to help companies navigate the challenges of using AM.”
Franck Mouriaux, general manager, structures, at Ruag Schweiz, adds: “The partnership between Altair, Morf3D and Ruag Space puts together the perfect ecosystem to revolutionise the way space components are engineered, produced and qualified. This breakthrough is absolutely mandatory for us to face the challenges of the new space industry and remain competitive.”
Back in the UK, a new, wholly-publicly-funded international research project being led by the University of Sheffield’s Nuclear Advanced Manufacturing Research Centre seeks to explore another of additive manufacturing’s main selling points: the ability to repair existing parts.
The Nuclear AMRC's additive manufacturing cell using wire-feed gas tungsten arc technology, operated by technology lead Udi Woy
This four-year, €2.6 million AMOS project (Additive Manufacturing Optimisation and Simulation platform for repairing and remanufacturing of aerospace components) will investigate a range of direct energy deposition techniques, including the wire-feed gas tungsten arc process used in the Nuclear AMRC’s bulk additive cell, that combines welding tools with automated control to accurately deposit and melt metal powder or wire. Many of these techniques are already used in aerospace and other industries to build new parts to near-net shape. Material research will focus on three widely used aerospace alloys: Ti6Al4V, Inconel 718 and 300M alloy steel. The project is supported by the European Commission through the Horizon 2020 programme and also by Canadian public sector funding agencies.
“There’s a host of additive manufacturing technologies available to aerospace manufacturers, but they tend to be focused on new production rather than repairing damaged parts,” says Dr Rosemary Gault, European project coordinator at the University of Sheffield AMRC. “The AMOS project is bringing together some of the world’s leading research organisations and companies to identify which additive technologies are best suited for repair and remanufacture, and develop them for commercial use.”
The AMOS consortium includes nine partners from Canada, France, Sweden and the UK, including research organisations, top-tier aerospace manufacturers and specialist technology developers.
Professor Yaoyao Fiona Zhao of the Additive Design and Manufacturing Lab of research partner McGill University, Montreal, Canada, says: “The project will provide a fundamental understanding of thermal and mechanical behaviour of powder and wire material during deposition. It will also provide a simulation and optimisation platform for industrial partners to further develop their component-specific applications.”
Moving from study to implementation of AM, Premium Aerotec has begun series production of 3D-printed metal parts for the Airbus Group at its site in Varel, northern Germany. Industrial series production began of a double-walled pipe elbow in the fuel system of the A400M transport aircraft. These complex components were previously produced from individual cast parts that were then welded together to form one assembly.
To support its latest move, the Airbus subsidiary built a new production hall for the additive manufacturing of titanium parts, complete with three machines from Concept Laser (ES Technology, 01865 821818). In the hall, two M2 Cusing Multilaser machines and one X line 1000R machine produce 3D parts in the LaserCusing selective laser melting (SLM) powder bed process. Another X line 2000R, featuring a build envelope of 800 by 400 by 500 mm and two 1 kW lasers, is expected to be added in summer.
At the same time, the company concluded a cooperation agreement with Concept Laser for further industrialisation of AM for applications in aviation, the further development of the plant and process technology, as well as the QA systems, plus the qualification of new powder alloys. Concept Laser CEO and president Frank Herzog says: “This cooperation marks an important milestone for the industrialisation of 3D metal printing in aircraft construction and undoubtedly also sends a signal to other industries. The network will work together to improve the value chain.”This article was first published in the June 2016 issue of Machinery magazine.
