Cleared for take-off

Materials World magazine
,
3 Aug 2015
Front bearing aero engine component

A new research centre is at the forefront of 3D printing science for aerospace. Natalie Daniels reports from the opening of Coventry’s Manufacturing Technology Centre

Engineers have successfully produced the largest front bearing aero engine component using 3D-printing technology. The 1.5m-long and 0.5m-thick titanium part contains 48 aerofoil parts. The component was designed by Rolls-Royce, in collaboration with the recently opened Manufacturing Technology Centre (MTC) in Coventry and the University of Sheffield..

Rolls-Royce used a new form of additive layer manufacturing (ALM), Arcam’s electron beam melting technology, to print complex shapes using ultra-thin layers of metal powder melted with a laser. Rolls-Royce has used ALM to repair components for more than five years, but this is the first time the company has used the technique to build complex components. 

Dr Clive Hickman, CEO of MTC, commented on the collaboration, ‘This project has been a key step in proving the industrial viability of the process and shortening manufacturing lead times in this application by more than 30% compared with conventional methods of manufacturing. There is no doubt that additive manufacture has the potential to transform manufacturing.’ Rolls-Royce has said the technology could be used to reduce the weight of parts such as brackets.

Titanium balls printed using electron beam meting technology.

The XWB-97 engine will be tested later this year on the Boeing 747 flying test bed, however, initially the XWB-97 will not contain the ALM component. Rolls-Royce have stated that they will not commit to a production time, ‘We don’t want to put a date on it. We have a lot of work to do on scalability before making a commitment to production,’ says Alan Newby, Chief Engineer.

The next generation

This is a significant breakthrough for the MTC National Centre for Net Shape and Additive Manufacturing, which formally opened its doors on 22 June. The centre forms part of a UK commitment to develop additive manufacturing. MTC National Centre Technology Manager, David Wimpenny said, ‘In the UK we have a world class manufacturing community, but we are not doing enough to drive innovation through exploration.’ The centre’s priorities will be to design, inspect, validate and research effective production processes as well as bridge the gap between university-based research and manufacturing.

The Aerospace Research Centre is part of the MTC’s research and development campus and Advanced Manufacturing Training Centre, due to open later this year. This will provide onsite apprenticeship training in manufacturing and engineering, up-skill manufacturing engineers and develop graduate engineers and industrial designers.

Forward thinking

Wimpenny describes his desire to exploit additive manufacturing technology, saying, ‘Beyond changing the shape of parts, we are starting to think about developing materials, specifically ceramics, and coming up with new techniques to get parts to net size. Then we are looking at functional graded materials, and mixing materials to print down patterns to extend their properties. I am starting to think about mixing functions, such as mechanical and electrical performance that could sense and adapt to the environment – that is my roadmap for the next 20 years.’

The MTC is currently looking into net shape to design for specific processes, as well as concentrating on the performance of lightweight parts. ‘Aerospace is definitely leading the way in additive manufacturing, but in jewellery and automotive industries, people are slowly starting to see the benefits. This is why it is so important for us to educate other sectors on what can be done with these technologies,’ says Dr Ross Trepleton, Group Technology Manager for the MTC.

A few grey hairs

Trepleton adds, ‘I think the UK is already a world expert in additive manufacturing, but what we do need to do is exploit it correctly. The next step is industrialisation.’ And the imagination doesn’t have to go to far to see the wider benefits in other sectors. The ceramics industry could benefit from this technology. ‘Additive manufacturing does have great potential in the ceramics sector, but there are fundamental issues that need to be addressed in order to make it a robust process,’ says Stuart MacLachlan, Head of R&D at Lucideon. Due to the refractory nature of the materials, research needs to be done to tap into this area. The results could be beneficial, particularly in the area of health care and dental materials. MacLachlan adds, ‘Where you are seeking to do a bespoke piece for applications within a body or mouth, for example, is where we could see an advantage, and also where you want to create geometrical features in engineering applications,’ he said. ‘We need to make sure the UK is not behind in ceramics for additive manufacturing.’

The next step for the MTC is to ensure new manufacturing techniques are commercialised and exploited in the UK with the support of designers and engineers. As Trepleton says, ‘We have a predominantly young workforce. However, it is nice to have some grey hairs around the place to bring a dose of realism around what we are trying to do.’

Trending worldwide

On the other side of the Atlantic, GE Aviation has also been making waves in ALM after announcing it will open a new assembly plant in Indiana to build 3D-printed fuel nozzles for the aerospace industry. The LEAP engine features 19 fuel nozzles, carbon fibre composite blades, and parts made from CMCs. The 3D-printed parts are five times more durable than the previous models and have reduced the number of brazes and welds from 25 down to five. They are also 25% lighter than their predecessor. GE Aviation has estimated it will produce more than 100,000 3D-printed parts by the close of this decade. The LEAP engine is not expected to enter service until 2016 on the Airbus A320neo.

The Manufacturing Technology Centre:

The training centre hopes to have 1,000 people on the manufacturing engineering apprenticeship by 2020

The National Centre was jointly funded by the Aerospace Technology Institute and Innovate UK, part of £60m funding by Government and industry for the development of new high-tech aerospace technology

UK Business Minister Anna Soubry announced a £10m competition to find game-changing aerospace technologies