Interfacial stresses in single-side composite patch-repairs with material tailored bondline

ABSTRACT

A stress-function approach to investigate the stress state in an adhesively bonded single-side composite patch-repair system containing a through-thickness hairline defect in the substrate experiencing far-field tensile stresses is presented. The obtained results indicate that the peak adhesive stresses can be significantly minimized, and they can be more uniformly distributed over the bondlength employing a material tailored bondline in lieu of a homogeneous bondline. The proposed model can be used as a simple and efficient analytical tool for designing such composite crack-patch systems and to examine the effect of loss of interface stiffness due to an existing defect and/or damage in the bondline.

KEYWORDS:

• Adhesives
• composites
• interfacial stresses
• material tailoring
• patch-repair
• variational method

Funding

The authors wish to acknowledge the support of the Masdar Institute of Science and Technology through MI/MIT cooperative agreement (Award No:12MAMA1).