New composite material is tougher than flame, lighter than metal
Direct flames and high-energy battery fires quickly break standard polymer composites. Engineers had to choose between heavy titanium composites or ceramic composites, which tolerate heat but involve greater manufacturing complexity and cost.
Extending composites into metal territory
To address this trade-off, the EIC-funded(opens in new window) C-PREG 400 project helped to develop FireX-Preg – a high-temperature prepreg platform designed to bridge the gap between conventional polymer composites and complex ceramics, enabling lightweight composite solutions to replace metals in demanding high-temperature applications. “With FireX-Preg, our objective was not simply to develop a composite that survives higher temperatures,” notes Giuseppe Galimberti, project coordinator and CEO at Nano-Tech. “We wanted to make high-temperature composites easier to manufacture, easier to integrate with existing materials and applicable to components where composites could never previously replace metals.” The FireX-Preg platform represents a new generation of high-temperature prepreg technology, based on a hybrid ultra-high-temperature matrix(opens in new window) and protected by new intellectual property. The material can be reinforced with carbon, glass or hybrid fibres and achieves a thermal threshold of DMA-Tg ≥400 °C. Yet, its utility extends beyond surviving heat: it acts as a thermal shield, stops burning if ignited and withstands exposure to jet fuels and chemicals. Given that it will not off-gas in space and will permit electromagnetic signals to pass straight through, the material could fit naturally into satellite systems and communications hardware.
Easier to mould, simpler to recycle
From an industrial perspective, FireX-Preg eliminates the manufacturing bottlenecks that typically kill new materials. Instead of locking factories into long, costly cure cycles, it adapts to standard equipment including autoclave, out-of-autoclave and press moulding. Curing takes 90 min at 135 °C or 60 min at 180 °C. For high-volume lines, it supports hot-stamping cycles in just 15 min at 180 °C. Furthermore, its co-curing capability changes how components are designed. Engineers no longer need to build an entire structure out of specialised materials; instead, they can lay FireX-Preg strictly where heat and fire protection are needed, while using standard structural composites elsewhere to optimise cost and weight. The Glass-FireX-Preg variant (FireX-Preg reinforced with glass fibre) adds a compelling sustainability advantage for aircraft interiors, where glass-fibre composites are common and fire-retardancy requirements strict. “Cured parts can go straight into standard glass-production furnaces as raw feedstock without stripping away the matrix, returning the composite directly to its original industrial ecosystem and providing a cleaner end-of-life pathway than traditional phenolic resins,” explains Galimberti.
Tested under fire: helicopter and electric aviation
The material’s capabilities have been demonstrated at component and system levels rather than laboratory test coupons. In a representative helicopter firewall programme, replacing a 1.61 kg titanium unit with FireX-Preg reduced component weight by up to 48 % while lowering production costs by up to 57 %. The material proved equally effective in electric aviation safety tests. During a full-scale battery fire test involving 216 fully charged cells, the FireX casing contained the event completely, preventing any flame, erosion, structural perforation or hot gas leakage. The FireX-Preg platform has successfully progressed from the laboratory to industrial adoption thanks to its flexible processing, quick cure cycles, hybrid compatibility and proven test results. “Moving forward, we are working on programme-specific aerospace certifications and introducing electrical conductivity for future electromagnetic interference shielding applications,” concludes Galimberti.