Printing planes: additive manufacturing brings quieter, lighter aircraft

Kostas Soumilas, vice-president of engineering, technology and quality at GKN Aerospace ASEA, tells James Scoltock about new developments in additive manufacturing

How much development has there been in the type of materials used in additive manufacturing over the past five years?

Additive manufacturing (AM) is of vital importance, offering a step change in the design of lightweight and cost-optimised structures as it gives the ability to make parts that previously were impossible or expensive to manufacture.

Our focus has been in titanium and nickel-based alloys. We also have engagements in academia investigating new materials suitable for additive manufacturing, with PhDs sponsored in the UK and in Sweden. GKN Aerospace’s AM technology enables our customers to break new ground by flying quieter, lighter and more cost-effective than ever before, contributing to a sustainable future of the aerospace industry.

What impact have these material changes had on manufacturing processes?

The true market potential of these material changes hasn’t hit our primary markets yet. However, the potential of substituting titanium into aluminium-based structures remains a performance opportunity which we’ve seen adoption of with some customers. New materials implementation into aerospace is a long journey and we’re excited for the opportunity that future platforms will yield for technology insertion. 

What work is being done so metal parts can be made quicker, more easily and more cost-effectively so they can be used more widely in industrialised applications?

We’ve built a dedicated product insertion and production team in the UK, which holds a separate, additional AS9100D quality management system approval specifically developed to enable additive manufacturing opportunities in aerospace. Production requirements and cost targets are being used to then inform our R&D direction as we drive towards series production in civil markets.

A significant focus of our R&D efforts today is in topics that can have tangible business impact on reducing recurring and non-recurring costs. We’re working to develop new non-destructive testing and post-processing solutions to drive industrialisation areas in particular. We’re also focused on the machine productivity and reliability, and what future automation technologies could be implemented to reduce our recurring costs.

Does the application impact on the above, and are different industries achieving this at a different rate than others. Aerospace is often seen as leader – is it the same with industrialisation on additive manufacturing?

The application where we’re applying our technology can certainly affect our industrialisation timescales. Within aerospace we’re working with our customers and the airworthiness authorities to establish rapid routes to industrialisation, and taking a product performance-based approach where appropriate. Every application we are developing and manufacturing is teaching us how to go faster and move towards a standardised family or process qualification route.

We do see other industries applying AM technologies in really exciting ways. There are industrial applications in the food industry where the design freedoms on offer can be exploited with a lower set of barriers to entry, and we also see medical industry success at really significant scale now in titanium. 

A sub-genre of materials and structures – lattices for example – are now being used. What impact is this having on AM and the technologies that can be created from it?

Lattice structures are certainly a very interesting application. Today, our primary experience of these types of structures is in R&D, but we have a number of demonstrators within our technology portfolio where we’re using lattices for both structural and functional applications.

In particular, we’ve made a number of acoustic demonstrators for our special products division and this remains an area we’re interested in exploring further.

What developments are you seeing in composite and multi-material additive manufacturing, and how is this impacting on business?

We’re less active in this space at the moment than perhaps in lattices and foams, but we have a fairly robust technology watch on where AM technology could go. We have a couple of PhDs sponsored in multi-material AM with our partner universities, and we’re integrated together in the UK with our composites research teams to continually test the market opportunity for composite AM.