Date of Award


Document Type


Degree Name

Master of Science


Department of Aeronautics and Astronautics

First Advisor

Marina B. Ruggles-Wrenn, PhD


Carbon nanotubes (CNTs) exhibit outstanding mechanical, electrical, and thermal properties, but are a challenge to effectively implement into macroscopic composites for aerospace applications. This research investigates the mechanical properties and performance of a newly developed hybrid NanoStitch composite, alongside a control polymer matrix composite, at room temperature. Both composite material systems investigated in this work have quasi-isotropic layup. Monotonic tension-tofailure, tension-tension fatigue, and creep tests were performed to characterize the performance of the composites under cyclic and sustained loading. Experimental results obtained for the quasi-isotropic NanoStitch composite were compared to those obtained for the quasi-isotropic control composite. The properties and performance of the quasi-isotropic composites are also compared to previously investigated cross-ply composites with 0/90 and 45 fiber orientations. Optical microscopy was used to examine and characterize the failure mechanisms for both quasi-isotropic material systems. Scanning electron microscopy was employed to examine the CNT forests on a fracture surface of a quasi-isotropic composite specimen failed in cyclic fatigue.

AFIT Designator



A 12-month embargo was observed.

Approved for public release. Case number on file.