A joint development from three companies - EconCore, Toray Advanced Composites and Bostik - has the potential to upend the use of thermoset sandwich components in aircraft interiors.
The three companies came together to provide a sustainable solution to the elaborate and time-consuming method used today to produce these parts.
Expensive and labour-intensive, the process currently used to manufacture parts based on conventional sandwich layup in aerospace, relies on phenolic prepreg skins and phenolic impregnated aramid honeycomb core. The thermoset system requires lengthy and expensive handling and processing of the sandwich components into the final part, which can take several hours, including the curing process
Optimised for safety, the new product uses Toray Cetex reinforced thermoplastic laminates as the skin material, EconCore’s thermoplastic honeycomb core with FST-resistant chemistry, and Bostik’s flame retardant thermoplastics polyester web adhesive. The new material has successfully passed fire, smoke and toxicity regulations applying to aircraft interiors.
It offers other benefits as well. Using EconCore’s continuous process and compression moulding, the new thermoplastic technology, suitable for different thermoplastic materials, can take around 60 seconds to form the desired shape. And using a reinforced thermoplastic composite laminate from Toray as skin allows the material to be easily moulded rather than going through a rigorous process of being covered in phenolics, setting, followed by being shaped by hand.
“With the FST thermoplastic honeycomb technology, we are looking for cost savings at both ends; within the continuously produced honeycomb core and panel, as well as within the fast, easy and clean conversion of a sandwich panel into a lightweight sandwich part, ” said Tomasz Czarnecki, COO of EconCore,
While the thermoplastic honeycomb part is less time consuming to make, the thermoplastic solution is also by far more sustainable. Not only can the thermoplastic honeycomb skin be easily recycled, shredded and repurposed into composites, the traditional phenolics, used for curing, have been replaced with a web adhesive from Bostik, which is flame retardant and meets the fire, smoke and toxicity requirements.
The use of adhesive reduce the complexity of adhesive application processes and offers a clean, repeatable assembly method - ‘while bringing added value such as fire retardancy to lightweight panels’, said Talitha Van Drom, business development manager at Bostik.
“This application demonstrates the versatility of thermoplastic composite technology, and the efficiencies it can bring to processing technologies throughout the value chain,” concluded Frank ten Napel, segment manager Aircraft Interiors and High Performance Industrial for Toray.