Liège-based company Safran Aero Boosters designs, develops and produces subassemblies, equipment and test stands for aircraft and rocket engines. As a partner to major engine-makers, its products are used on many of today’s commercial jet engines, as well as the Ariane launcher.
“The chosen technology will enable Safran Aero Boosters to produce its parts more efficiently, as well as to optimise their shape, weight and strength.”
The blades used in turbojet engines are made from a titanium alloy that is strong and light but hard to machine: up to 90% is lost as shavings when employing traditional techniques. Safran Aero Boosters asked Sirris to help it select a suitable additive manufacturing technology in order to produce optimised parts (lighter, stronger, more compact, etc.) that comply at least as well with aviation sector standards but with greater ease and less material wastage.
With Sirris’s help, Safran Aero Boosters opted for an additive manufacturing technology called electron beam melting (EBM). This involves spreading a bed of metal power then building up the required shape layer by layer by melting the powder using an electron beam. Sirris used its EBM equipment to produce a series of blades and to demonstrate the feasibility of the project. In particular, the material wastage was very significantly reduced: the ‘buy to fly’ ratio (the ratio between the mass of material used to produce the part and the mass that actually ends up in the aircraft) fell from 10 to almost 1.
Based on the tests carried out by Sirris, Safran Aero Boosters ended its feasibility study with a positive conclusion and in late 2015 purchased a state-of-the-art machine. Sirris is now helping with the technology transfer. A new four-year Marshall project called Aero+ has got under way, in which a Walloon consortium comprising Safran Aero Boosters, Sirris, UCL, ULB, ULG, CRM, SAMTECH, AMOS and V2i will optimise the parts and validate them for use in the aviation sector.