Friday, November 2, 2012
Bio-inspired Hierarchical Materials: Micromechanics, GPU-Based Simulation and 3D Printing
Matthew Begley, Professor, Department of Mechanical Engineering, University of California, Santa Barbara
This talk will describe theoretical and experimental aspects of developing synthetic materials that exploit ordered phases of ductile and brittle materials, i.e. 'brick and mortar' microstructures analogous to those found in several shellfish. The first part of the talk will address the questions "if we wish to make a synthetic analogue to nacre, what should it be made of and what what should it look like? The second part of the talk will address the question: "how would you make such a material?" In the first part of the talk, an analytical micromechanical model of uni-axial deformation will be presented that elucidates the underlying composites theory being exploited. This model will be then used to identify promising material systems and processing targets (i.e. brick size and layout, mortar thickness, etc.). This is followed by a description of an emerging computational study of the material's anisotropic behavior for complex loading, using a particle-based simulation approach that exploits graphical processing unit (GPU) parallelization. Preliminary results will be presented that enable more detailed connections between microstructure, local damage mechanisms and macroscopic properties. In the second part of the talk, efforts to synthesize such microstructures using ink-jet printing will be described: in this approach, printable inks are created from colloidal suspensions of ceramic and metal nanoparticles, delivered via projected droplets to define phase morphology, and consolidated. The potential and limitations of the approach will be described, both in terms of developing new composites and more generally for 3D printed ceramic/metal structures.