Mixed mode І/ІІ fracture prediction of blunt V-notched nanocomposite specimens with nonlinear behavior by means of the Equivalent Material Concept

Mixed mode I/II fracture of ductile nanocomposite components containing blunt V-notches was studied both experimentally and theoretically. Fracture tests were conducted on the rectangular plates containing a central rhombic hole with four blunt V-shaped corners, which were fabricated for two different notch angles of 30° and 60° and various notch rotation angles and notch tip radii. Load-carrying capacities (LCCs) of the notched nanocomposite specimens were experimentally obtained by performing tensile tests. The reformulated Equivalent Material Concept (EMC) was used in conjunction with the maximum tangential stress (MTS) and the mean stress (MS) criteria to theoretically estimate the experimental results of LCC. The theoretical results obtained confirmed that both combined criteria could provide very good predictions to the experimentally obtained LCCs of the notched ductile nanocomposite specimens without needing any nonlinear analyses. Fracture mechanisms were also investigated in detail for the V-notched nanocomposite specimens using the optical and the scanning electron microscopy photographs taken from the fracture surfaces of the tested specimens. The photographs captured revealed that the specimens failed evidently by ductile failure mechanism, identified mainly by the shear bands.