Emerald Group Publishing Limited
Copyright © 2008, Emerald Group Publishing Limited
High strength two-part epoxy adhesive - meets aerospace FST standards
Article Type: Materials From: Aircraft Engineering and Aerospace Technology: An International Journal, Volume 80, Issue 3.
Diversified technology company 3M has developed what it believes to be the world's first two part structural epoxy adhesive to meet aerospace fire smoke and toxicity (FST) standards (when tested standalone) without the need for additional treatments or surface coatings. The adhesive meets the requirements laid down by FAR 25.853 (a) flaming mode, JAR 25.853 (a) flaming mode and ABD 0031 and AITM 2.0002A as defined by the US flight authorities, European flight authorities and Airbus, respectively.
Scotch-Weld adhesive 7246-2 B/A FST is said to be set to substantially simplify many aircraft interior manufacturing tasks by allowing builders to complete assembly and FST compatibility operations in a single step. The versatile product may also replace several different types of conventional adhesive, simplifying stocking requirements and improving productivity.
Scotch-Weld adhesive 7246-2 B/A FST is a room-temperature curing structural two-part epoxy paste adhesive system. Its thixotropic, non- sag formulation makes it easy to apply without dripping or deformation. The product is ideal for a host of aerospace interior tasks, such as the corner splicing of honeycomb panels, insert bonding and the bonding of tubular ducting.
Scotch-Weld adhesive 7246-2 B/A FST reportedly allows completed assemblies to meet FST requirements without additional surface treatment. The product is light tan in colour to match conventional honeycomb skin materials, and can be over painted using the same surface coatings as the panels without leaving unsightly shadows.
“Our aerospace customers need to produce assemblies that meet extremely demanding FST standards. Up until now, those requirements have precluded them from taking advantage of modern easy-to-use structural epoxy adhesives where the adhesive will form part of the outer surface of the finished product,” explains John Lester, Key Account Manager at 3M.
“Because this new product meets FST requirements itself, it will dramatically simplify a host of edge finishing, gap filling and insert bonding operations. We expect Scotch-Weld adhesive 7246-2 B/ A FST to become the standard choice for the final assembly of many aircraft interior structures.”
Scotch-Weld adhesive7246-2 B/A FST is said to have a typical worklife of 45min and reaches handling strength in 3 to 4h under the same conditions. The product is available in an EPX duo-pack cartridge for simple, accurate application or in bulk containers for hand mixing or use with automated mixing equipment.
Compatible with most common aerospace interior substrates including aluminium honeycomb, polycarbonate, glass/phenolic panels, polyetherimide and polyphenylsulfone, Scotch-Weld adhesive7246-2 B/A FST is stated to be resistant to damage by water, salt spray, jet fuel and mineral oils.
Details available from: 3M UK, Tel.: +44 (0)161 237 6174.