Title:

Toward the Next Generation of Multiscale Multifunctional Hybrid Composites

Speaker:

Dr. Marwan Al-Haik

Affiliation:

Department of Mechanical Engineering,University of New Mexico

When:

Tuesday, March 30, 2010 at 11:00:00 AM   Add to Calendar

Where:

Montgomery Knight Building, Room 317

Host:

Bethany L. Smith
bethany.smith@aerospace.gatech.edu
404-894-3251

Abstract

The seminar will cover some results of ongoing investigations on generating novel composite materials based on carbon nanostructures. One approach utilizes the alignment of single wall carbon nanotubes in a bulk composite. An epoxy/single wall carbon nanotubes (SWCNTs) composite was processed inside high magnetic fields (15-25 Tesla) to mediate the reorientation of the carbon nanotubes. Based on this study, it was evident that magnetic alignment is a phenomenon closely related to the self-organizing process of the polymeric system. The thermal and electrical properties of the nanocomposite were significantly enhanced by the alignment of the carbon nanotubes during the magnetic processing. Numerical simulations based on molecular dynamics complemented these experimental investigations. A second approach aims to develop hybrid composites with enhanced blast]resistance capabilities over the current technology. This approach entails the growth of carbon nanofibers/ nanotubes on structural microscale carbon fibers and fiberglass to improve the strength, deformability and energy absorption characteristics of the polymeric and cementitious structural composites. Different hypothesis have been developed to optimize the surface growth of carbon nanotubes on carbon/glass fibers. A novel technology; Graphitic Structures by Design (GSD) has been developed to eliminate the high vacuum and high temperature environments typically needed for standard chemical vapor deposition (CVD) technology. GSD is applicable for wide range of catalysts, requires atmospheric pressure and much lower temperatures making the growth process more affordable. Experimental investigations of the composite under tensile and shear stresses showed the significance of the fabrication parameters on the mechanical characteristics of the composite. Preliminary simulations also showed the promising potential for the newly generated hybrid composites for blast resistance applications. Design of a multilayer carbon fiber composite laminate subjected to an uncertain blast event is demonstrated. The case study shows that CNTs contents about 1% are capable of producing blast resistant carbon-epoxy composites with acceptable probability of failure.

Biography

Dr. Marwan Al-Haik is an Assistant Professor at the Department of Mechanical Engineering/University of New Mexico. He received his PhD from Florida State University in 2002. He worked as a postdoctoral research associate at the National High Magnetic Field Laboratory, Tallahassee FL between 2002-2004. His current research interest includes the synthesis and characterization of nanomaterails for structural, electrical and bio applications. His research also includes constitutive modeling of engineering materials at multiscale. Dr. Al-Haik is an NSF-CAREER Awardee (2009) and he received the Air Force Research Lab Summer Fellowship (2008), the Army Office of Research DURIP award (2009). He is the author/co-author of 38-refereed journals articles and 3 issued US patents applications.