Accession Number:

ADA533318

Title:

Differential Multiscale Modeling of Chemically Complex Materials under Heavy Deformation: Biological, Bioinspired and Synthetic Hierarchical Materials

Descriptive Note:

Final rept. 1 Aug 2006-30 Jun 2010

Corporate Author:

MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF CIVIL AND ENVIRONMENTAL ENGINEERING

Personal Author(s):

Report Date:

2010-06-01

Pagination or Media Count:

121.0

Abstract:

This research was focused on modeling and design of high stress and impact mitigating structures, utilizing nanoscale patterning and hierarchical biomimetic concepts. The eventual goal is to create heterogeneous, hierarchical designs for thin coatings and bulk materials, capable of providing enhanced ability to mitigate high rate impact and deformation. The potential of a structure to mitigate impact, large stress and large deformation is characterized by i the ability of the material to dissipate energy under high rate deformation, ii the resistance to brittle fracture by crack formation under high rates, and iii the ability to redistribute load underneath a thin external coating film. To achieve this, our efforts are centered on the development of a holistic atomistic based core model of the deformation and fracture mechanisms of thin nanostructured coatings. Using atomistic simulation, we study the behavior of nanostructured composites under heavy impact loading, incorporating different material combinations that are coupled in various arrangements, at different length scales, arranged in a hierarchical pattern. The material combinations feature divergent characteristics such as hard-soft or brittle-ductile, since mixture of materials with disparate properties are often found in Natures toughest and mechanically most robust materials, used to provide protective surfaces e.g. in seashells, bone, spider silk. We demonstrated the development and application of such material design paradigms in studies of bone, silk, collagen and similar materials, enabled through the development of multiscale models. Our work has pushed the frontier of biomechanics and biomaterials modeling to enable a bottom-up perspective of key issues that define robustness, strength and adaptability of biological and biologically inspired mechanically relevant materials for numerous applications.

Subject Categories:

  • Biology
  • Miscellaneous Materials

Distribution Statement:

APPROVED FOR PUBLIC RELEASE