Study of Shear Dominant Delamination in Thin Brittle-High Ductile Interface
2015 (English)In: National Agency for Finite Element Methods and Standards (NAFEMS), 2015Conference paper, Abstract (Other (popular science, discussion, etc.))
Thin laminates of Aluminum (Al) and Low Density Polyethylene (LDPE) is an essential constituent of food packages where these two substrates are bonded together with a thin layer of LDPE acting as adhesive. Noticeably, Al is a low ductile/quasi brittle material whereas, LDPE is highly ductile. The mechanism of delamination and strength of bond between the interfaces dictates the continuum and damage behaviour of this composite. However, measuring the shear delamination is challenging as conventional test methods have limitations when the substrates are very thin. This study explains a method that uses uniaxial tensile testing on the pre-cracked specimen of this composite to find energy dissipation due to shear delamination and successfully use it in Finite Element Simulation in Abaqus. The delamination was observed in a narrow strip region close to fracture surfaces and measured with special visualization aid. Similar response was found in FEM simulation. Scanning Electron Microscopic (SEM) study of delaminated interface confirms the domination of shearing. In a cohesive zone modelling in Finite Element Simulation software, the shear delamination energy was used as input parameter along with an arbitrary bi-linear cohesive law. The substrates’ constitutive response was modelled considering non linear plasticity and softening. Finally proposed delamination energy separation method was validated with comparison between the physical tests and FEM simulations.
Place, publisher, year, edition, pages
Shear Dlamination, Thin Packaging Material, Composites, Cohesive Zone Modelling, Finite Element Simulation, Tensile Testing
IdentifiersURN: urn:nbn:se:bth-11607OAI: oai:DiVA.org:bth-11607DiVA: diva2:900613
NORDIC Seminar: Simulating Composite Materials and Structures, Stockholm