Polymer composites must evolve to stay ahead in the aerospace sector


The aerospace sector was one of the earliest and most significant adopters of carbon fibre-reinforced polymer (CFRP) material. With this adoption driven by their superior strength and stiffness-to-weight ratio, composites can make up over 50% of the structural parts in the latest models for narrow- and wide-body civil aircraft. However, this dominance is under threat, with emerging metal alloys and additive manufacturing as some of the key contenders.

The innovations associated with composites have not been exhausted; many processes are reinventing this class of material and advancing more than just the mechanical properties in the process.

IDTechEx has extensively covered the composites, lightweight metals and 3D printing fields and has now launched a report titled: ‘Additive Manufacturing and Lightweight Materials for Aerospace and Defence 2018-2028’, which highlights some of the key advancements, including lighter composites, multi-functional composites and emerging opportunities.

This report looks at the key emerging lightweight technologies crucial for the aerospace and defence sectors and includes over 40 interview-based company profiles with some of the most significant players changing this field.

There are many progressions to improving the lightweight performance of a composite part, including next-generation pre-impregnated material and the rise of high performance thermoplastics. These are all extensively explored in the report, but two notable advancements are discussed below.

Thin-ply composites from spread-tow fibres are gaining increasing attention. This involves spreading the fibres for a reduced density (typically below 75 gsm) and a stronger homogeneous fibre-matrix interaction. The early markets for these are motorsport and sporting goods, but aerospace is the significant next step. This material is already being used by HAECO for interior seating on its A350 aircraft and has been explored in advanced stages for structural roles in unmanned aircraft systems (UAVs). Comprehensive profiles of both Oxeon, with its TeXtreme range, and North Thin Ply Composites can be seen alongside the report.

At a much earlier stage is the use of pure boron fibres for polymer reinforcement. This is different to the monofilaments previously explored and it is proposed that this fibre can replace carbon fibre in much the same way that carbon fibre has replaced aluminium in the very long term. The fibres are synthesised via a laser chemical vapour deposition route and led by companies such as Free Form Fibres.

‘Multi-material’ and ‘multifunctionality’ are the two biggest terms in structural componentry. The ability to add functionality to a composite part is significant for performance, added value and

The routes discussed in the report are challenging and often take advantage of new materials, such as graphene and carbon nanotubes (CNTs) in nanocomposites, or advanced manufacturing processes. They are at different stages in terms of reaching commercialisation. The drivers for adoption, technology approaches and academic to commercial players are also discussed in the report.

The polymer composite evolution is not just limited to the roles we have come to expect. There are many examples of this including:
  • Natural bast fibres for aerospace trolleys;
  • Braided material for fan cases, vanes and pipes becoming ever more prevalent;
  • Recycled material, which is driven predominantly by lifecycle assessments and the need for improved waste management; and
  • Hybrid parts to optimise the use of high-performance materials.

Finally, it is important to note the role that enhanced automation, extending into 3D printing of composites, can play in expanding their uptake. Automation is a key facilitator to give the material greater design freedom and cost efficiency.

More information on this field is given in the report, which can be found at https://bit.ly/2LKgYio