Levering his knowledge in structures, Dr. Pirmoz has investigated the micro-structure of Carbon Nanotube Fibers to characterize their mechanical and electromechanical behavior and move towards the way that can advance us to development of new high-performance structural materials.

Pictures Courtesy of Micro and Nano Fabrication Laboratory, UMD

Carbon nanotube (CNT) fibers (yarns) are microscopic assemblies of carbon nanotubes in the form of continuous fibers that have significant potential for technological applications. However, the mechanical and electromechanical response of CNT fibers are yet not well understood. Careful observation of the Scanning Electron Microscope (SEM) images of our several tested samples, we realized that the hierarchical structure of a CNT fiber can be idealized as a pack of fibrillars comprised of twisted and entangled CNT bundles. Based on this idealized concept, a multiscale finite element (FE) model is proposed that discretizes the fiber in three levels:
(i) nanoscale model of bundles comprising CNTs,
(ii) mesoscale model of CNT fibrillars formed by bundles,
(iii) microscale model of the fiber comprising twisted CNT fibrillars.
Part of the obtained results of the proposed analysis approach is published in Mechanics of Materials.

Idealized components of a CNT fiber (Pirmoz, 2022)
Proposed hierarchical and multi-scale model for CNT fiber (Pirmoz, 2022)
Three-dimensional finite element model of CNT fiber (Pirmoz, 2022)
Axial strain in two different fibrillars (Pirmoz, 2022)
Axial strain distribution in cross-section of CNT fiber (Pirmoz, 2022)

References:

A Pirmoz, Computational Modeling of Mechanical and Piezoresistive Response of Carbon Nanotube, PhD Dissertation, Department of Civil and Environmental Engineering, The Catholic University of America, Washington DC, 2022.

A Pirmoz, JL Abot, F Avilés, Simulation of mechanical response of carbon nanotube yarns underuniaxial tensile loading; Mechanics of Materials 165, 104144, 2022.

A Pirmoz, JL Abot, JC Anike. Meso-Scale Computational Simulation of Mechanical Response of Carbon Nanotube Yarns; Proceedings of the American Society for Composites—Thirty-third Technical Conference, 2018.

CONTACT