Natural Functionally Gradient Materials and Their Biomimetic Study

Natural functionally composite materials have super acclimatization and extraordinary properties after a long period evolution.The gradient structure widely exists in them.In recent years,the structures and properties of natural functionally gradient materials have been researched in order to develop biomimetic structure or biomimetic materials.Results indicate that the natural functionally gradient materials have the property of the strongest component enduring the most stress,which make the best use of everything.In this paper,the gradient structure and its excellent performance of several kinds of natural materials,such as bone,tooth,shell,tree and bamboo,are introduced.The relevant biomimetic studies are reviewed and the further investigation suggestions are proposed.