Structural Adhesive Bonding
With the changing dynamics of structural design, assembly, and the choice of using dissimilar substrates, adhesives are becoming more accepted in the industry. With a broad experience in structural bonding, Structural Composite Designs can assist in the selection and validation of the appropriate adhesive for your application. Validation tools include analysis of bonded joints using FEA and structural lab testing. If necessary, Structural Composite Designs can provide certification tests against various agencies to determine if the adhesive will pass the certification requirements. Such agencies have defined performance requirements in the automotive, marine, truck and wind-turbine industries. After the adhesive is qualified, the appropriate method of dispensing is selected. Working with global equipment dispensing manufacturers, Structural Composite Designs can provide assistance in the equipment selection, installation, preventative maintenance procedures and provide on and off-site trouble-shooting support for the equipment.
Courtesy of ITW Plexus, USA.
Epoxy adhesives have a long track record for structural bonding. These adhesives are also available in one-part and two-part systems. The one-part systems are typically heat cured and need to be refrigerated until they are used. The two-part epoxies are room temperature curing adhesives that have good high temperature properties, excellent chemical resistance and can bond some traditionally difficult to bond materials. The disadvantages of epoxy adhesives include their intolerance to off-ratio mixing, poor flexibility and difficulty in adhering to some plastics and composites especially without surface preparation.
Methacrylates are excellent structural adhesives with few limitations. Typically methacrylates come in two-part room temperature curing systems. Mix ratios are typically either one-part adhesive to one part activator or 10 parts activator to one part adhesive. The advantages of methacrylate adhesives include the ability to adhere to a wide range of substrates with no surface preparation, excellent flexibility, and tolerance to off-ratio mixing and good chemical and thermal resistance. The main disadvantage of methacrylate adhesives is their distinctive odor, which is not harmful, but some people find unpleasant.