Abstract
•Finite element modeling of essential work of fracture (EWF) of ductile crack of thin aluminium sheet.•Analytical modeling for the EWF obtained from FEA.•Experimental validation of the proven model.•Relate the essential work (we) with the JC of elastic-plastic fracture mechanics.•To obtained a description of fracture toughness of thin aluminium sheet.
The fracture toughness of a commercial thin aluminium sheet (1.2mm) is measured by the essential work of fracture (EWF) method using a double-edge notch tension specimen. The EWF method is implemented at room temperature at a deformation speed of 2mm/min. The basics of the EWF method and its relation with J-integral are described in this paper. Ligament yielding is observed to occur at the peak of the load-displacement curve. Following this, necking and tearing occur in the softening region. The EWF for the thin aluminium sheet is measured as 51.5kJ/m2. However, the non-essential work of fracture is dissipated in the tearing process after yielding, causing expansion of the plastic region. In this work, two advanced finite element models, namely, non-linear and linear J-Integral finite element models, are implemented to simulate the essential work of fracture test. The results for the essential and non-essential fracture indicate good agreement with EWF fitting. The linear extended finite element (XFEM) model yields more accurate results than the J-integral method. Crack opening displacement is measured by the EWF method, and is compared with the results of the studied models.