Date of Award
1-1-2014
Document Type
Dissertation
Degree Name
Ph.D.
Organizational Unit
Daniel Felix Ritchie School of Engineering and Computer Science
First Advisor
Maciej Kumosa, Ph.D.
Second Advisor
Davor Balzar, Ph.D.
Third Advisor
Yun Bo Yi
Fourth Advisor
Peter Laz
Fifth Advisor
Iwona Jasiuk
Keywords
Aging, Composites, Mechanical testing, Ozone, Polymers, Thermal analysis
Abstract
The next generation High Temperature Low Sag Polymer Core Composite Conductors (HTLS PCCC) can experience harsh in-service environments including high temperature and highly concentrated ozone. In some extreme cases, it is possible that the conductors will experience temperatures of up to 180°C and ozone concentrations as high as 1% (10,000 ppm). Therefore, the primary goal of this research was to determine the most damaging aging conditions which could negatively affect the in-service life of the conductors. This included characterizing the aging in ozone and at high temperature of the HTLS PCCC hybrid composite rods and neat resin. It was found that exposure to 1% ozone for up to three months at room temperature did not negatively affect the flexural performance of either the neat resin epoxy, or the hybrid composite rods. When aged up to a year at 140°C no detrimental effect on flexural performance of the composite was observed, as opposed to aging at 180°C, which had a very negative effect on the properties. The aging of the epoxy at 140°C was driven almost entirely by temperature and the effect of 1% ozone, even at that temperature, was insignificant for aging times up to ninety days. A finite element model was developed and showed the residual stresses developed after aging at 140°C for a year were minimal, but for temperatures higher than 160°C were substantial. From this it was determined that the aging was thermally driven, and atmospheric high temperatures were the most damaging conditions for the PCCC conductors.
Publication Statement
Copyright is held by the author. User is responsible for all copyright compliance.
Rights Holder
James M. Middleton
Provenance
Received from ProQuest
File Format
application/pdf
Language
en
File Size
202 p.
Recommended Citation
Middleton, James M., "Aging of a Polymer Core Composite Conductor Under Combined Ozone and Temperature Conditions" (2014). Electronic Theses and Dissertations. 427.
https://digitalcommons.du.edu/etd/427
Copyright date
2014
Discipline
Materials Science