Print Email Facebook Twitter Multi-material adhesive joints with thick bond-lines Title Multi-material adhesive joints with thick bond-lines: Crack onset and crack deflection Author Lopes Fernandes, R. (TU Delft Structural Integrity & Composites) Budzik, Michal K. (Aarhus University) Benedictus, R. (TU Delft Structural Integrity & Composites) Teixeira De Freitas, S. (TU Delft Structural Integrity & Composites) Date 2021 Abstract This study investigates the fracture onset and crack deflection in multi-material adhesive joints with thick bond-lines (≈10 mm) under global mode I loading. The role of adherend-adhesive modulus-mismatch and pre-crack length are scrutinized. The parameters controlling the crack path directional stability are also discussed. Single-material (i.e. steel-steel and GFRP-GFRP) and bi-material (i.e. steel-GFRP) double-cantilever beam joints bonded with a structural epoxy adhesive are tested. The joints are modelled analytically, considering a beam on elastic-plastic foundation, to include characteristic length scales of the problem (e.g. adhesive thickness, plastic zone) and numerically using Finite Element Model. An empirical relation, in terms of geometrical and material properties of the joints, that defines the transition between non-cohesive and cohesive fracture onset is found. Above a specific pre-crack length the stress singularity at pre-crack tip rules over the stress singularity near bi-material corners, resulting in mid-adhesive thickness cohesive fracture onset. However, the cracking direction rapidly deflects out from the adhesive layer centre-line. Positive T-stress along the crack tip is found to be one of the factors for the unstable crack path. Subject Fracture onsetMode IThick bond-line To reference this document use: http://resolver.tudelft.nl/uuid:96fe92b2-7fc9-41e9-bd68-440fa924aa03 DOI https://doi.org/10.1016/j.compstruct.2021.113687 ISSN 0263-8223 Source Composite Structures, 266 Part of collection Institutional Repository Document type journal article Rights © 2021 R. Lopes Fernandes, Michal K. Budzik, R. Benedictus, S. Teixeira De Freitas Files PDF 1_s2.0_S0263822321001483_main.pdf 5.35 MB Close viewer /islandora/object/uuid:96fe92b2-7fc9-41e9-bd68-440fa924aa03/datastream/OBJ/view