TY - JOUR
T1 - Failure of a pre-cracked epoxy sandwich layer in shear
AU - Askarinejad, S.
AU - Thouless, M.D.
AU - Fleck, N.A.
N1 - Copyright:
© 2020 Published by Elsevier Masson SAS.
PY - 2021/2
Y1 - 2021/2
N2 - Adhesive joints are frequently used in automotive, maritime and construction applications, yet joint reliability remains a concern. The purpose of this study is to develop a fracture mechanics methodology for the failure of an elastic-brittle lap-shear joint comprising a thick adhesive layer (an epoxy, of thickness on the order of 10 mm) sandwiched between thick steel adherends. This configuration is of practical application to ship-building, such as the bonding of a superstructure to the underlying hull. A modified thick-adherend shear test (TAST) is designed, and specimens are fabricated, with a range of interfacial pre-crack length and a range of adhesive layer thickness. The failure of samples with no pre-crack is governed by a critical value of corner singularity, whereas the failure of samples with long pre-cracks is governed by a critical value of interfacial stress intensity factor. Predictions for the dependence of failure load upon layer thickness and pre-crack length are obtained by analysing the elastic stress state for both a corner singularity and for an interfacial crack. Both the experimental results and the theoretical framework are useful in the design and fabrication of reliable lap-shear joints that comprise a thick elastic adhesive layer.
AB - Adhesive joints are frequently used in automotive, maritime and construction applications, yet joint reliability remains a concern. The purpose of this study is to develop a fracture mechanics methodology for the failure of an elastic-brittle lap-shear joint comprising a thick adhesive layer (an epoxy, of thickness on the order of 10 mm) sandwiched between thick steel adherends. This configuration is of practical application to ship-building, such as the bonding of a superstructure to the underlying hull. A modified thick-adherend shear test (TAST) is designed, and specimens are fabricated, with a range of interfacial pre-crack length and a range of adhesive layer thickness. The failure of samples with no pre-crack is governed by a critical value of corner singularity, whereas the failure of samples with long pre-cracks is governed by a critical value of interfacial stress intensity factor. Predictions for the dependence of failure load upon layer thickness and pre-crack length are obtained by analysing the elastic stress state for both a corner singularity and for an interfacial crack. Both the experimental results and the theoretical framework are useful in the design and fabrication of reliable lap-shear joints that comprise a thick elastic adhesive layer.
KW - Thick-adherend shear test
KW - Adhesive
KW - Fracture toughness
KW - Corner singularity analysis
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85093089969&partnerID=MN8TOARS
U2 - 10.1016/j.euromechsol.2020.104134
DO - 10.1016/j.euromechsol.2020.104134
M3 - Article
SN - 0997-7538
VL - 85
JO - European Journal of Mechanics - A/Solids
JF - European Journal of Mechanics - A/Solids
M1 - 104134
ER -