The influence of cracks, notches and holes on the tensile strength of cellular solids

Finite element simulations of two-dimensional cellular structures with defects were performed to study the influence of defect size and cell size on the tensile strength of the cellular solid. Three types of defects were considered: circular holes, sharp cracks and notches. The net section strength, defined as the peak tensile load divided by the remaining intact area in the section with the defect, was determined for a range of defect sizes and cell sizes. For the circular holes, the net section strength was found to be independent Of hole size, and equal to the tensile strength of the intact honeycomb. For cracks and notches the net section strength showed a notch-strengthening effect, exceeding the tensile strength of the intact honeycomb and increasing with crack or notch depth. The results were sensitive to the cell size for the crack defects but riot for the hole or notch defects. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.