Adhesive film meets fire, smoke and toxicity regs

1 min read

A versatile, low density adhesive film has been launched that helps aircraft interior manufacturers cut production times and meet increasingly stringent FST regulations.

According to 3M, developer of the new adhesive film, the product is the first adhesive film for aerospace sandwich panels that fulfils stand alone FST regulations. 3M AF3070 FST can be used to finish edges, splice cores and fill gaps in honeycomb sandwich panels. The film is co-cured with the panels to deliver a high quality edge finish and helps to ensure compliance with FST requirements. Lightweight and stiff, sandwich panels are a critical part of modern aircraft interior designs, but joining and finishing these panels can be a costly, time consuming process. This process is made more difficult because of the requirement to pass stringent fire, smoke and toxic gas emission (FST) regulations, which greatly limit the number of acceptable adhesives and joining materials. 3M's AF3070 FST is a double-sided, foaming film with an advanced epoxy adhesive. It includes its own in-built, halogen-free, FST system that allows it to meet FST requirements, according to both the Airbus ABD 0031 directive and the FAR 25.853 standard. "This is the first time that interior manufacturers have been able to obtain both foaming characteristics and FST properties in the same product," said John Cobb, transportation manager for 3M UK and Ireland. "Against a background of increasing cost pressures, rising quality demands and ever-tightening safety regulations, this product is going to solve a lot of pressing problems for aircraft interior manufacturers." Typical applications for AF3070 FST include overhead luggage compartments, partition walls and fixed wall, ceiling and floor panels. As it is co-cured with the sandwich panels, the film saves manufacturing time by eliminating post-cure finishing work, while its halogen-free FST system improves operator safety during the manufacturing process. During cure, which can take place at 120°C or 180°C to match the panel system, AF3070 FST expands between 50 and 75 per cent, filling gaps and providing a strong, safe bond. The product's foaming characteristics also make it ideal for the filling of complex gaps in sandwich structures.