Mixed-mode fracture of adhesively bonded metallic joints under quasi-static loading

• Published in: Engineering fracture mechanics 2010-11, Vol.77 (17), p.3434-3445
• Main Authors: Hafiz, T.A., Abdel Wahab, M.M., Crocombe, A.D., Smith, P.A.
• Format: Article
• Language: English
• Subjects: Adhesive bonding; Adhesive joints; Bonding; Exact sciences and technology; Exact solutions; FEA; Fixtures; Fracture mechanics; Fracture mechanics (crack, fatigue, damage...); Fundamental areas of phenomenology (including applications); Linear Elastic Fracture Mechanics (LEFM); Mathematical analysis; Mixed-mode loading; Physics; Solid mechanics; Static elasticity (thermoelasticity...); Strain energy release rate; Strain energy release rate (SERR); Structural and continuum mechanics
• ISSN: 0013-7944; 1873-7315
• DOI: 10.1016/j.engfracmech.2010.09.015

Quasi-static tests have been carried out to characterise mixed-mode fracture using a Double Cantilever Beam (DCB) specimen. The DCB consists of equal thickness mild steel adherends bonded with FM-73M epoxy adhesive and is tested under pure mode I, pure mode II and a range of mode-mixity conditions, using a relatively simple loading fixture. The test method is analysed using closed-form and finite element methods, which agree well provided that the adhesive deformation is considered. The strain energy release rate components at fracture are presented in a conventional G I (mode I)– G II (mode II) failure plot using closed-form Linear Elastic Fracture Mechanics (LEFM) methods reported previously in the literature. The results showed that the strain energy release rate is enhanced in the situation of the mode II (in-plane shearing) dominated mixed mode condition as compared to the mode I (opening mode) dominated mixed mode.