About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
|
Coatings and Surface Engineering for Environmental Protection II
|
Presentation Title |
Mechanisms of Corrosion Inhibition Afforded by Exfoliated Graphite Nanocomposites: Can Exfoliated Graphite Compete with Graphene? |
Author(s) |
Rachel D. Davidson, Sarbajit Banerjee |
On-Site Speaker (Planned) |
Rachel D. Davidson |
Abstract Scope |
Chromium-based coatings remain the dominant corrosion-inhibiting technology in the aerospace industry despite the well-documented carcinogenic effects of hexavalent chromium biproducts. Graphene-based coatings offer an intriguing alternative given the ultrathin, impermeable nature of the 2D material. However, galvanic corrosion, limitations in dispersion, and processing challenges have limited its large-scale use. We have explored performance of unfunctionalized exfoliated graphite-polymer composites as a function of exfoliated graphite loading. Mechanisms of corrosion inhibition are understood through combined AC conductivity and electrochemical impedance spectroscopy studies monitoring coatings submerged in saline solutions over 100 days. At low loadings, unfunctionalized exfoliated graphite dispersed in polyetherimide offers excellent protection forming electrically isolated 2D inclusions creating extended tortuous pathways for diffusion of corrosive species, while higher loadings allow for deleterious percolative networks to form resulting in galvanic corrosion. |
Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |