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All Subjects: nanoparticle alignment
Creators: Song, Kenan

Engineering Education: How Today's Youth Learns CAD Skills in an Online Environment

Description

The purpose of this project is to assess how well today’s youth is able to learn new skills in the realm of engineering through online video-conferencing resources. Each semester of this last year, a class of students in both 3rd and 6th grade learned about computer-aided design (CAD) and 3D printing through their laptops at school. This was done by conducting online lessons of TinkerCAD via Zoom and Google Meet. TinkerCAD is a simple website that incorporates easy-to-learn skills and gives students an introduction to some of the basic operations that are used in everyday CAD endeavors. In each lesson, the students would learn new skills by creating increasingly difficult objects that would test both their ability to learn new skills and their overall enjoyment with the subject matter. The findings of this project reflect that students are able to quickly learn and retain new information relating to CAD. The group of 6th graders was able to learn much faster, which was expected, but the class of 3rd graders still maintained the knowledge gained from previous lessons and were able to construct increasingly complicated objects without much struggle. Overall, the students in both classes enjoyed the lessons and did not find them too difficult, despite the online environment that we were required to use. Some students found the material more interesting than others, but in general, the students found it enjoyable to learn about a new skill that has significant real-world applications

ContributorsWerner, Matthew (Author) / Song, Kenan (Thesis director) / Lin, Elva (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)

Created2021-05

Microstructural Control in Fabricating Multifunctional Carbon Fibers

Description

Precursors of carbon fibers include rayon, pitch, and polyacrylonitrile fibers that can be heat-treated for high-strength or high-modulus carbon fibers. Among them, polyacrylonitrile has been used most frequently due to its low viscosity for easy processing and excellent performance for high-end applications. To further explore polyacrylonitrile-based fibers for better precursors, in this study, carbon nanofillers were introduced in the polymer matrix to examine their reinforcement effects and influences on carbon fiber performance. Two-dimensional graphene nanoplatelets were mainly used for the polymer reinforcement and one-dimensional carbon nanotubes were also incorporated in polyacrylonitrile as a comparison. Dry-jet wet spinning was used to fabricate the composite fibers. Hot-stage drawing and heat-treatment were used to evolve the physical microstructures and molecular morphologies of precursor and carbon fibers. As compared to traditionally used random dispersions, selective placement of nanofillers was effective in improving composite fiber properties and enhancing mechanical and functional behaviors of carbon fibers. The particular position of reinforcement fillers with polymer layers was enabled by the in-house developed spinneret used for fiber spinning. The preferential alignment of graphitic planes contributed to the enhanced mechanical and functional behaviors than those of dispersed nanoparticles in polyacrylonitrile composites. The high in-plane modulus of graphene and the induction to polyacrylonitrile molecular carbonization/graphitization were the motivation for selectively placing graphene nanoplatelets between polyacrylonitrile layers. Mechanical tests, scanning electron microscopy, thermal, and electrical properties were characterized. Applications such as volatile organic compound sensing and pressure sensing were demonstrated.

ContributorsFranklin, Rahul Joseph (Author) / Song, Kenan (Thesis advisor) / Jiao, Yang (Thesis advisor) / Liu, Yongming (Committee member) / Arizona State University (Publisher)

Created2020