Paramount to additive manufacturing is the ability to create objects we wouldn’t have previously thought possible. We’ve heard a lot about these ‘impossible objects’, sometimes it’s the AM experts that are offering these breakthrough ideas to various industries and other times it’s the clients themselves, major industrial companies, asking ‘is this even possible?’
The aerospace industry has provided some major headline grabbing developments over the last few years and that’s been even more evident in just the last few months. Talk to anyone about 3D printing and chances are they’ve heard one of the more famous examples like the one about the plane that’s being flown with 1,000 3D printed parts or the one with the huge 3D printed turbine.
The radical fact about aerospace is we’re not just talking about prototypes but real functional parts that are being used in aircraft, some of which have been on commercial vehicles for the last year without the need for a huge parade and ceremony to back them up,
Airbus was the name behind the recent sexy “1,000 3D printed parts on board an aircraft” story that saw Stratasys FDM 3D Production Systems used in place of traditionally manufactured metal parts.
Stratasys, Aerospace & Defense Business Development Manager, Scott Sevcik, explained: “With Airbus they identified a risk within the supply chain and with bringing parts to the aircraft in time so they looked at 3D printing as an alternate means of production. They spent about a year qualifying the material and the process so they could have high confidence in putting these parts on aircraft and meeting certification requirements. Once they reached that threshold of having the specifications in place and being able to meet them that opened up a world of opportunity for them and they took advantage of it and in the A350 case, printing a large number of parts for the first few aircraft.”
Delivered in 2014, the parts were 3D printed using Airbus certified ULTEM 9085 resin which provides high strength to weight ratio and is flame, smoke and toxicity (FST) compliant for interior aircraft applications.
“With aerospace everything takes time,” Scott commented. “The relevant materials have now been on the market for a few years so companies can get that testing under their belt and that understanding, to understand material properties better and build that confidence. With a company like Airbus that’s very significant.”
Materials are high on the agenda in the sector with developers working on new, high strength resistant materials that are tailored towards aerospace applications. GKN Aerospace recently launched a three-year project to develop a new titanium powder for aerospace components. The Titanium Powder for net-shape component manufacture (or TiPOW) program is a £3.1 million collaborative research project which will investigate and define suitable development, production and reusability of titanium alloys and powders for aerospace.
Demonstrating the force of these dedicated materials, rocket manufacturer, United Launch Alliance is set to fire a 3D printed component on board the Atlas V launch vehicle next year. Also using ULTEM 9085, the Environmental Control System duct was printed on a Stratasys Fortus 900mc 3D production system, consolidating its previous 140-part count to just 16. Scott explained:
“With United Launch Alliance they kind of take it a step further. They’re actually looking at applications on their vehicles and redesigning them to reduce part count, weight and cost and really take advantage of not just an alternative faster production method but a method that can produce a part that couldn’t have been produced before.”
Redesigning the launch component significantly reduced the installation time and was able to lower part production costs by a huge 57%. The component has undergone extreme environmental tests to ensure its capability, which proved the part was able to withstand the same intense stress and pressures faced by the traditionally manufactured, original part.
Scott added: “With the design freedom you can consolidate parts which simplifies the supply chain and reduces costs and risk. There are a lot of benefits to being able to redesign. You can take that a step further in applications where you can actually replace metal components with plastic components and have a pretty dramatic weight reduction. “
Certification is a major part of the development process for AM in the aerospace sector with parts and materials having undergo rigorous testing and certification examinations to ensure they reach industry standards of functionality, quality and safety. The U.S. Federal Aviation Administration recently approved the first 3D printed part to fly in a commercial jet engine developed by GE Aviation, which took flight in April.
Greg Morris, Leader, Additive Technologies, GE Aviation, explained: “Using additive manufacturing, we cut the design process by a year: we could test prototypes quickly and move the best design to production much faster than conventional manufacturing techniques. Once in production, the part can also be made in a fraction of the time.”
The new T25 3D printed sensor housing made from cobalt-chrome alloy took one year less to manufacture than the original part. Powering Boeing’s 777 planes, the GE90 engine series is the world’s most powerful engine and GE Aviation is currently working with the aerospace giant Boeing to retrofit more than 400 GE90-94B jet engines with the 3D printed part.
Greg, added: “In contrast to traditional machining methods, additive manufacturing enables us to build parts from the ground up. This advanced technique means less material waste and more complex parts that can be built precisely to optimise how they work inside a machine. Additive manufacturing will change the game forever by freeing engineers to design parts without the traditional limitations imposed by conventional manufacturing.
GE Aviation is currently working on several next-generation engines that benefit from advance manufacturing techniques. On the LEAP engine for narrowbody aircraft and the GE9X for the Boeing 777X aircraft, GE Aviation will produce part of the fuel nozzles with additive manufacturing, a project which has already received more than 8,500 orders.
A new era of design
Effective design for AM requires sophisticated software and UK-based Additive Design Consultancy (ADC) has been assisting the aerospace industry with AM components and assemblies using specialist software that allows efficient design and testing of components. Most recently, ADC has been conducting research into the potential of AM in RF antenna design by looking at a range of different technologies that allow the design freedom to create perfect geometry’s to bring new levels of efficiency and performance.
ADC director, Adam Arnold, explained: “We are particularly looking at Aluminium as it has the electrical properties and great strength to weight ratio. However there are further weight improvements to be gained from looking at electroplated polymer based printed materials. This is of great interest in aerospace and particularly UAV platforms for performance reasons."
The key requirement from customers in the aerospace sector is weight reduction but in order to achieve that CAD designs must meet all the formal standards of aerospace engineering to produce quality parts capable of withstanding intense environments and performance targets. Adam explained:
"Being such an open ended design process, designing to get the most out of AM for weight reduction is challenging many engineers, who do not have the tools, training or experience to produce geometrically very complex designs."
Adam believes the importance of this knowledge and expertise is vital to highlighting advanced manufacturing methods as a competitive form of production.
“Large companies, like airframe manufacturers, have teams of people looking into the problem, and big budgets to throw at it. However, the majority of the market, being made up of tier 1 and 2 suppliers to the likes of Airbus, do not. In the future, the higher management of these suppliers will need to buy in to the idea that making their products using well designed AM parts will give them a significant competitive edge in terms of performance and weight, and thus invest internally or buy in expertise."
With more companies looking at the possibilities of advanced manufacturing and implementing these technologies into real end-use parts, aerospace is proving itself as the ultimate model for that predestined shift from prototyping towards manufacturing.
Scott added: “When someone does something like print a 1,000 parts and put them on aeroplanes – I don’t want that to be a story, I want that to be commonplace and I think it will be very, very soon.”