An ordinary state-based peridynamic model for toughness enhancement of brittle materials through drilling stop-holes

Official URL: http://dx.doi.org/10.1016/j.ijmecsci.2020.105773

In this paper, the ordinary state-based peridynamic (OSB) is used to simulate and study the effects of different- shaped stop-holes with different combinations on crack dynamics in brittle materials in order to establish a detailed knowledge about the toughening effect of internal features that can be in the form of holes and pores. Using the OSB analyses, a new easy-to-apply technique is presented to toughen the materials against crack prop- agations. As a first case study, the high accuracy of peridynamic approach in damage prediction is demonstrated through solving a collection of numerical and experimental benchmark problems. Moreover, the bi-hole, parabolic, branched, bi-parabolic , and mixed-parabolic combinations of stop-holes under tensile loading, and the T-shape, I- shape, bi-linear, linear , and linear-parabolic combinations of stop-holes under shear loading are suggested for no- tably enhancing material toughness and are practically and functionally compared with each other. Generally, the suggested geometries are proven to be highly effective on toughness enhancement of materials with a relative ease of implementation, in comparison to other internal features such as micro-cracks. In addition, a further case study is carried out on the effects of the distance of stop-holes from the initial crack-tip on crack dynamics and material toughness, in which it is observed that every hole has a specific μ-range, and thus, the crack dynamics are affected by the hole if and only if the crack enters this range. Overall, the arrestment and accelerating effects of the stop-holes on crack dynamics are carefully explained numerically and conceptually, which will help en- gineers and designers to maximize the positive effects of stop-holes on material toughness and design a tougher micro-structural material using easily applied defects.