Coatings made with graphene—the thinnest, strongest material ever made—can help prevent UV degradation and corrosion on wind turbine blades, new research shows.
A flake of carbon that was the research focus for the 2010 Nobel Prize for Physics, graphene has been found to conduct heat and conduct electricity as well as copper. It is almost transparent, yet so dense that not even helium can pass through it, experts say.
“Graphene is stronger and stiffer than diamond, yet can be stretched by a quarter of its length, like rubber. Its surface area is the largest known for its weight,” said Andre Geim, one of two Nobel Prize winners recognized in October for their experiments with graphene.
Now, a Wichita State University researcher has found that graphene, extracted from graphite, also has significant potential as a coatings additive.
Protecting Wind Turbine Blades
In his project, Dr. Bangwei Zhang, of WSU’s Department of Mechanical Engineering, set out to develop a new nanocomposite coating material to protect advanced fiber-reinforced composite wind turbine blades against UV degradation and corrosion from weathering.
Zhang’s paper, Using graphene in coating materials to prevent UV degradation on advanced composite materials, was presented earlier this year at WSU’s 6th Annual Symposium on Graduate Research and Scholarly Projects (GRASP).
In his paper, Zhang notes the increasing popularity of composite materials for a wide variety of applications, include wind power energy. However, he notes, most research shows that conventional coating methods and materials have shorter lifetimes than the composite material itself.
Zhang added graphene powder to paint and used an airless sprayer to apply the coating 3 mils thick to the surface of an advanced composite material. The graphene comprised 2% of the coating.
Once the specimens were coated, according to ASTM B117, they were put into a UV chamber for five to 16 days to observe damage differences. The UV intensity of 16 days’ exposure is equivalent to two years of regular sunlight, Zhang said. Specimens were also put into salt corrosion chambers to simulate weathering.
Using a tensile test, a water contact angle test, and AFM imaging, Zhang determined that the graphene-laced coatings helped protect the material surface from UV damage and degradation.
“[G]raphene is a good inclusion to be mixed with original paint,” Zhang concluded.