Keeping one step ahead

Composite engineers in the aerospace industry have every right to be pleased with their achievements in the last two decades.

The typical long-range airliner has gone from 15% of structural weight made from composite material to 50%, with applications including such vital components as the wings. Similar changes have occurred in military aircraft and greater gains with drones. Aero engines are using very high temperature composites in the hot end of the engine to match the composite structures at the cooler front end. Even the cars someone might buy – not just super cars – are available with significant carbon composite structures, particularly if electrically-powered.

Is now the time to say our technology is mature and we will focus on squeezing incremental improvements out of our materials, machines, and processes? Our answer to you is a definite no!

The big challenge now is to get cost and extra weight out of our composite structures, whether aerostructures or automotive. We need a step change in our attitude to new innovations and a willingness to adopt some older ideas that seem to have gotten stuck in just a few niche applications. This will bring about a second revolution.

Innovative processes and materials can reduce manufacturing times and lead to better quality, complex, fastener-free, integrated structures which give significant cost savings.

So, what are these ‘magical’ new processes and materials that are going to save weight and cost? Well to be truthful few are new – they are mostly recent developments of materials or processes that failed to be fully-developed the first-time round. These innovations include: infusion processes such as VARTM and multiple variations on this theme. These have been around for decades making niche products, such as radomes and propellers. Now, with quality improved by Bombardier and Albany/SAFRAN, it is finding applications with wings (C Series) and fan blades (CFM Leap engine); Thermoplastic materials are now showing their true benefits with welding systems enabling complex parts such as elevators and rudders to be made by assembling simple press formed parts, with no fasteners. Processes developed by Fokker are now flying with parts on the Gulfstream 650. Fokker is proposing that future development of these techniques could be used to make a fuselage; Fibre Metal Laminates (FML) were used extensively on the A380 and then went out of favour. Fokker and Premium Aerotec have been working on automating the process to spread their usage; Nano materials cover at least three categories: a) Small particles, often ceramic like materials; b) Nano tubes have remarkable properties, but structural applications seem scarce; c) Graphene is the latest Nano-material with promising electrical properties.

These opportunities are exciting, but they give management a problem. Their staff, comprising design and manufacturing engineers and operations managers, have all been trained to use prepreg materials, either by hand layup or automated laminating by ATL or AFP. Customers are expecting cost reductions and suggest the use of newer technologies; the supplier is then faced with the risks of producing a fixed price, using a process with which they have no experience.

How does a company get its engineers quickly up to speed with new composite technologies? We suggest the Society for the Advancement of Materials and Process Engineering (SAMPE) can provide a solution. This technical society operates in the UK, Europe, North America, and Asia at the crossroads between industry and academia. It provides technical forums analysing all aspects of composite materials with many opportunities to network with experts in the latest developments.

Many long-term collaborations and joint R&D programmes have been started at SAMPE conferences. In the UK, we have our annual one-day seminar and in Europe we hold our SAMPE SUMMIT 17 in Paris before JEC World.

www.sampe.org.uk