Partners in a recently completed UK government funded NATEP (National Aerospace Technology Exploitation Programme) technology programme ‒ Composite Tooling and Engineering Solutions Ltd (CTES), SHD Composites Ltd (SHD) and Applied Graphene Materials plc (AGM) ‒ have subsequently made a significant step forward in demonstrating the viability of an exciting new materials development that has the clear potential to offer significant time and cost savings to aerospace composite tool designers.
SHD, working closely with the project partners, has developed a prototype tooling material that combines cure at initial low temperatures (80-90°C), with the ability to be post-cured to achieve a maximum service temperature in excess of 300°C. This cure flexibility enables the use of low-cost pattern materials and progression to a final production tool without the need for an expensive, time consuming and accuracy-losing intermediate tool phase, or manufacture of an expensive, metallic master model.
Graphene enhance material properties
The tooling resin chemistry has been enhanced by the addition of AGM’s A-GNP35 graphene nanoplatelets, significantly enhancing the matrix toughness and providing extra resilience against variations in processing conditions and resin micro-cracking over repeated production cycles. The graphene can be applied into the tool structure by addition into the bulk tooling material or discreetly targeted at critical regions by means of AGM’s Structural Ink® printing technology.
Demonstrating that a low-cost and high-performance material is possible
This new material has been developed with cost savings to major aerospace programmes in mind and in a technology zone where materials choice and tool design are inextricably and critically linked. The demonstrator was a 10m long CFRP AFP mandrel tool, engineered by CTES (manufactured by Retrac Composites Ltd, Swindon) and was purposely chosen as representative of the industry’s latest and highly demanding requirements.
Over coming weeks, the project team will be disseminating more details through industry forums. However, the outcome was very successful, delivering a fully functional composite tool and demonstrating the potential for significantly lower costs, while maintaining the highest performance.
From prototype to possible applications
Although the new materials technology remains at the prototype/prove-out stage, the project partners are already actively engaged with interested parties keen to access the benefits of the system. As well as proving out production robustness, development work has also progressed to the processing of the material “out of autoclave”, as well as the potential for applications in prototype tooling for high performing thermoplastic materials.
Source: The Graphene Council