| Abstract Scope |
In its millions of years of evolution, nature has created biological hard tissues we have not been able to synthesize in the lab in terms of their well-controlled ultrastructure. Examples are mollusc shells, bone, and teeth. As a result of their complicated hierarchical structures, biological hard tissues often exhibit extraordinary mechanical performance. For example, pores exist in bones and teeth. From the viewpoint of fracture mechanics, these “defects” are stress concentration sites and may be detrimental to their strength. However, defects are well tolerated by those hard tissues and do not readily develop into fracture. The fascinating structure-function relations of biological tissues have been a contact inspiration to the materials community in its quest for better designs of high performance materials. This presentation introduces some of the specific structural designs adapted by seashell, various teeth, and bone to resist fracture. Potential applications to materials designs will also be discussed. |