Investigation of Zinc- and Carbon-Nanoparticle-Based Nanocomposite Coatings

High performance coatings of pipelines should possess properties such as high adhesion to the substrate, low gas permeability, high corrosion resistance, etc. In this study, novel nanocomposite materials are studied for coating of steel plates. The coatings consist of two-layer composites with different nanoparticulates. Zinc particles, multi-walled carbon nanotubes (MWCNT), and graphene nanoplatelets (GNP) are used for the base layer bonded to the steel. Zinc particles are used as a filler and act as sacrificial anode against corrosion (cathodic protection). Hexagonal boron nitride (hBN) is added to the matrix for the second layers. Adhesion of the coatings is studied through pull-off tests. To examine the corrosion protection capabilities, cathodic disbondment tests are conducted on the coated steel plates. The gas permeability of the coatings is evaluated through a standard testing technique. Results show that addition of Zinc particulates could enhance corrosion protection. The addition of GNP and hBN nanoparticulates resulted in lower gas penetration. Results of this research will contribute to the development of advanced pipeline coatings.