Nacre composite resembles “brick and mortar” microarchitecture with interlaced ceramic platelets (bricks) separated by soft biopolymer (mortar). To find out what makes nacre so strong, the structure is examined on a nanometer scale. The secret to it’s phenomenal strength lies within the biopolymer itself. The microstructure consists of millions of organic fibers. Each fiber consists of nano-size modules (bumps). As tension is applied to the platelets, the modules unwind prior to fiber fracture.
This project will investigate fiber rupture processes in global and local load sharing models. Load previously carried by a failed fiber in a global load-sharing model, is shared equally by surviving fibers in the system. In a local load-sharing model, the load originally carried out by a failed fiber is shared by the nearest-neighbors of the ruptured fiber. Interpolating between the two models is important to Oak Ridge National Laboratory by optimizing real-time fiber rupture. A fiber bundle model with Worm-Like Chains (WLC) is used to represent the biopolymer force-displacement response of nacre.