Many biological materials, such as glass sponges, nacre or bone have a lamellar structure. While it is well known that weak interfaces between lamellae may deflect cracks and, thus, increase the toughness, we analyze the influence of periodic variations in Young's modulus. Even without weak interfaces, a ratio of 5 between maximum and minimum modulus can be sufficient to stop a crack in the vicinity of the stiffness minimum.
If you can't find a tool you're looking for, please click the link at the top of the page to "Go to old article view". Alternatively, view our Knowledge Base articles for additional help. Your feedback is important to us, so please let us know if you have comments or ideas for improvement.