Bonding
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Material Pre-treatment |
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Adhesive selection |
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Curing techniques |
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Special Processes |
Material Pre-treatment
To ensure optimum performance, surface preparation is vital to the bonding process. The type of treatment required depends on the substrates being used but in the case of aluminium material it usually involves degreasing and chemical etching of the surfaces to be bonded. Technical Resin Bonders has large scale alkaline and vapour degreasing with chromic/sulphuric acid etching and de-ionised water wash down facilities. Also available is an automated rapid process to apply a two part etch/primer system.
Adhesive selection
Modern adhesives are available in different systems and types. The choice of adhesives depend on the substrates which are to be bonded and the processing methods they will accept, the application of the finished product and the environment in which the product is used. With Technical Resin Bonders knowledge and its access to an extensive range, including epoxy, polyurethane and acrylic, very specific adhesives can be selected to meet the individual requirements of the product.
Epoxy adhesives are available in a flexible film form, they require no mixing of components and contain exact proportions of resin and hardener. They are supplied with protective paper/polythene on both sides. They are therefore clean, safe and easy to work with, can be cut be size and tacked to the surface to be bonded.
For very fast application, two part solvent free polyurethane adhesive can be sprayed on to the substrate using automated equipment that ensures an even coating of the correct weight.
Curing techniques
Different adhesive systems require very different curing techniques, determined not solely by the requirements of the adhesive itself but also by the limits imposed by the substrates which are to be bonded and further influenced by the function of the finished product.
With a total of 7 multi-daylight presses, the largest able to hold work pieces up to 3200mm x 1600mm and the majority capable of achieving curing temperatures of up to 180degC, Technical Resin Bonders have a massive capacity to produce bonded panels using the high pressure flat pressing method.
For more complex shaped products and materials, large ovens equipped with vacuum bagging facilities for applying pressure during the bonding process, are used.
In the case of very large flat panels, ambient temperature curing adhesives can be used and components can be held down under vacuum on a flat steel surface table that measures almost 5000mm x 2500mm.
Special Processes
Some processes, particularly those associated with space applications, bonding of intricate components and the use of advanced composite materials, demand that all stages are conducted in environmentally controlled clean areas. At Technical Resin Bonders a large clean room with an internal positive pressure situation has been specifically built to undertake such work.
A large freezer store room enables adhesives and advanced composite materials to be held in optimum conditions.