Design guidelines for composite patches bonded to cracked aluminum substrates

• Published in: Journal of adhesion science and technology Vol. 16; no. 2; pp. 197 - 211
• Main Authors: Aglan, H. A., Gan, Y.X., Wang, Q. Y., Kehoe, M.
• Format: Journal Article
• Language: English
• Published: Leiden Taylor & Francis Group 01-01-2002; Brill
• Subjects: Applied sciences; COMPOSITE PATCHES; Composites; DESIGN GUIDELINES; Exact sciences and technology; Forms of application and semi-finished materials; Polymer industry, paints, wood; STRUCTURAL REPAIRS; Technology of polymers; Design aids; Stress analysis; Cracked plate; Fiber reinforced material; Epoxy resin; Aluminium; Metal; Experimental study; Composite material; Boron fiber; Tensile stress; Stress distribution; Adhesive joint; Repair; Patch; Fracture mode
• ISSN: 0169-4243; 1568-5616
• DOI: 10.1163/156856102317293704

Design guidelines are proposed for boron fiber-reinforced epoxy composite patches bonded to cracked aluminum substrates. Stress analysis was performed on the composite patch bonded to an uncracked aluminum
substrate. The load transfer via the adhesive and the stress levels in the aluminum substrate and the patch were determined. The local stress and stress distribution in the repaired V-shape side cracked
substrates were obtained. The effects of crack length and patch geometries including the length and number of plies on the failure behavior of the repair were identified. The results were validated by static
tensile tests. It was found that the theoretical calculations were in agreement with the experimental results. This indicates that the proposed analysis can be used as design guidelines for composite repairs
of cracked structures. These guidelines coupled with a simple surface preparation technique developed in this work might aid composite patch installation in service.