Living in the plastic age

Mike Richardson met with Quadrant Engineering Plastic Products' global market manager for aerospace, Frank Johänning at the recent Paris Airshow to hear more about the company's latest Nylatron thermoplastic product.
Just imagine if a civil aircraft could be made entirely from plastic – wouldn't that be something? Could there ever be a day when we will see plastic planes flying? It's a vision that everyone connected with the plastics manufacturing industry must surely have but is it possible and more to the point, will it ever be cost-efficient.

One company aiming to find out is Quadrant Engineering Plastic Products (Quadrant EPP). As one of the world's leaders in the manufacture of semi-finished products, Quadrant EPP's materials range from UHMW polyethylene, nylon and acetyl to high performance polymers that resist temperatures to over 425 °C.

The company's rods, sheets, tubes and custom shapes are used to machine components for the aerospace industry, so I start by asking Quadrant EPP's global market manager for aerospace, Frank Johänning if plastic materials are gaining increasingly more prominence in aircraft manufacture.

“Plastics aren't new to aircraft interiors, but we see a lot of products that are, from our perspective, chosen specifically for their very high fire, smoke and toxicity (FST) performance levels,” he begins. “Equally, we also know of products that are being used and their FST performances are not very good. At the request of a major OEM, we began developing a multi-purpose nylon product that fulfils the flammability test requirements of Federal Aviation Regulations (FAR) 25.853.

“Our R&D team produced our latest thermoplastic product, Nylatron FST, which is based on polyamides. The base polymer, Ertalon was introduced to the aerospace industry over 30 years ago. Nylatron FST is based on the same polymer and provides a FST performance that fulfils FAR requirements.”

Quadrant EPP took the opportunity to announce the launch of its Nylatron FST during this year's Paris Airshow. Its features are claimed to make it the first engineering plastic product of its kind available as semi-finished shapes (rods and sheets). FST retardant capabilities enable it to resist extreme short term temperatures up to 175ºC and the material is said to be particularly suitable for any kind of application in aircraft interiors where metal parts, such as brackets, seal bushings, slide rails and duct seals or high performance polymers have traditionally been specified.

From the inside out

Johänning says the introduction of Quadrant EPP's Nylatron product was the catalyst to widen its portfolio and also extend the pyramid out from the plastics world.

“We always talk about the plastics pyramid, which has dedicated aerospace products for interior applications in the wider segment of the parameter. Ultimately, Quadrant EPP's overall target is to optimize systems and offer improved solutions through advanced materials allowing a higher level of functional integration. This can be achieved through the replacement of metals or also polymers. Plastic parts have already made huge advances within aircraft interiors, but we still see a lot of very high performing materials being used in areas where most of their properties aren't really required; they are being used just because of their FST properties.

“As lightweighting is one of the main drivers, airframe OEMs are feeling increasingly more commercial pressure from their customers. As a result, the OEMs are passing these demands down the supply chain. We want to provide a quality product that isn't completely over-specified for interior requirements, but safely fulfils the FST standards required.”

Quadrant EPP introduced Nylatron to the OEM over a year ago under a non-disclosure agreement. After just five months it was already in service and proved to be the fastest material approval the company has ever experienced.

“It's an OEM requirement we're satisfying and filling the value chain from bottom up, going through distribution, the various tier levels and the system integrators to make them aware and then to present it wholly to the OEMs within their programmes. We all know that the major programmes are more or less commercialised now and that the big OEMs have restructured to focus more on optimising modelling and subassemblies. From our perspective, the introduction of Nylatron fits very nicely into this trend because it makes everything more efficient, safer and replaces over-specified material.

“One major aircraft OEM is currently consolidating its international materials specifications under one global standard. Based on this we will start to redesign and globalise our complete aerospace portfolio. Starting with Nylatron 66SA, we will produce an entire polyamide range under the Nylatron brand with full aerospace approval. Our polyamide will be the first material followed by other materials, making that step from local European supply to global supply. This re-specification of materials, hopefully supported by the OEMs we are doing it with, will gain acceptance in the market.”

Plastic fantastic?

With aircraft design and engineering becoming increasingly more complex, whilst maintaining a close focus on safety and reliability, perhaps the vision of an ‘all plastic' plane may soon become a reality? Airframe OEMs now require light and flexible materials to withstand high temperatures and pressures, as well as maintaining their robustness throughout long periods of use. Nylatron FST would appear to address the need for durable and fire retardant plastic materials. “This is the vision that everyone in the plastics industry has and I think it is possible,” states Johänning. “The question is whether it's cost-efficient. There are areas where metals' cost versus performance ratio enables them to fit very well, so plastics will never replace all metals. The stability of metal by itself combined with its cost is still one of the most important factors keeping metal in these applications.

“Carbon fibre reinforced plastics (CFRP) are for extremely strong structures where they are out-performing metals by far. However it is still expensive to manufacture these parts based on thermoset materials and Quadrant sees a strong trend towards thermoplastics. The manually-intensive manufacturing of wings and larger elements will be replaced with more modular and automated manufacturing technologies; we're already moving in this direction.”

Johänning reckons Quadrant EPP's automotive industry experience in making composites extremely efficiently from a cost/performance ratio has given it a strong background in thermoplastics manufacturing and thermoplastic composites.

“Maybe over the next year we'll see that efficiency and experience in composites manufacturing finding its way into the aerospace industry,” he concludes. “If you look around Quadrant, you will find various CFRP shapes, so technology-wise we're ready to enter this market - not just with the technology itself, but also the process and the scale. I'm pretty sure that the next generation of major aircraft programmes will incorporate thermoplastic composite technology, but this is still ten years' worth of development work away.”

www.quadrantplastics.com