Paper Citing NAMD - Abstract
Katti, D.R.; Katti, K.S.; Ghosh, P.; Schmidt, S.
Exploring mineral biopolymer interactions to model mechanical response of interfaces in bio-nanocomposite, nacre
Computational Mechanics, Proceedings, 807-812, 2004
Nacre, the shiny inner layer of seashells is a biological nanocomposite exhibiting extraordinary mechanical properties compared to the properties of the constituents. Although, the composition of nacre is 95 to 98% aragonitic calcium carbonate and 2 to 5% organics consisting of proteins and polysaccharides, the fracture toughness is three orders of magnitude higher than monolithic ceramics. These extraordinary mechanical properties are attributed to the nano-microarchitecture of nacre. In the last few years a concerted effort has been made to delineate portions of the nacre nano-microarchitecture responsible for the mechanical properties using computational mechanics at various length scales [1-3]. The organic layer, approximately 20 nm thick is sandwiched between 5 micron diameter and 0.25 micron high hexagonal platelets of aragonite. Our previous work indicates that the organic layer must have one to two orders of magnitude higher elastic modulus compared to the properties exhibited by bulk organics [1, 2]. In this paper, we describe results of steered molecular dynamics simulations done to investigate the role of biopolymer-mineral interactions on the mechanical properties of the inorganic-organic interface and interphase in nacre.
