Impact of Interface Heterogeneity on Joint Fracture

Abstract

The effects of heterogeneities (weak zones in particular) in adhesive joints and their importance on overall fracture properties are relatively unknown, but doubtlessly they may be crucial in many applications. Using a model heterogeneous adhesive bond, represented by a given mixture of regions of strong and weak adhesion, we have studied the influence of interface variability on overall fracture energy (global energy release rate). Adopting the original Griffith-Irwin arguments, we have employed a simple, fracture scaling law. By varying relative proportions of the weak and strong interfaces, a nonlinear evolution of fracture energy was observed. This was contrary to expectations, cf. rules of mixtures. Inspired by rheological models (Maxwell, Voigt/Kelvin, etc.), an appropriate model was found empirically.

KEYWORDS:

• Adhesion
• Fracture
• Heterogeneity
• Rule of mixtures

Notes

One of a Collection of papers honoring Wulff Possart, the recipient in February 2012 of The Adhesion Society Award for Excellence in Adhesion Science, Sponsored by 3M.

Additional information

Notes on contributors

Michal K. Budzik

Michal K. Budzik is on leave of absence from Gdansk University of Technology, Faculty of Mechanical Engineering, Department of Materials Engineering and Welding, Gdansk, Poland.