Temporary Crack Repairs for Aluminum Structures on Surface Ships

Gougeon Brothers Inc. is submitting a proposal to address the need for a temporary repair procedure for 5xxx series aluminum U.S. Navy ship structures that have stress corrosion cracking issues. The proposal explains how an innovative toughened thixotropic epoxy adhesive can be used to wet out reinforcing fabrics to a surface with simple surface preparation. This concept takes advantage of the work already accomplished by NAVSEA with the permanent composite patch solution and simplifies the products and surface preparation. A thixotropic epoxy adhesive eliminates the use of liquids that can spill and eliminates the ability need to mix and measure. Cartridges that dispense a pre-measured amount of resin hardener through a static mixer will enable easy use aboard ship. The epoxy adhesive will be shear thinning which allows a gel like adhesive to easily saturate a lightweight reinforcing fabric. Testing to evaluate the performance of this repair method will include tensile adhesion, lap shear, and laminate strength testing to determine the ability to stop crack propagation. GBIs experience developing, manufacturing, and marketing epoxy resins and adhesives will enable this repair kit to be commercialized to the U.S. Navy, U.S.C.G., and operators of commercial ships.