Please wait.'

Page is loading'


Home  > Raw materials & technologies  > Technologies  > Metakaolin-based geopolymer coatings on me...

Tuesday, 27 October 2020
pdf
Raw materials & technologies, Technologies

Metakaolin-based geopolymer coatings on metals

Thursday, 6 August 2020

A new study reports on geopolymer coatings on metals by airbrush spray deposition.

Metakaolin-based geopolymer coatings were prepared by airbrush spray deposition. Image source: Destina – stock.adobe.com (symbol image).

Metakaolin-based geopolymer coatings were prepared by airbrush spray deposition. Image source: Destina – stock.adobe.com (symbol image).

Metakaolin-based geopolymer coatings with a thickness of about 60 μm were prepared on 2024 Al alloy and low carbon steel substrates by airbrush spray deposition.

Curing in a sealed condition led to a limited geopolymerisation reaction and corrosion of the uncoated surface in the metal substrates. Fourier-transform infrared spectroscopy and X-ray diffraction measurements of the coatings cured in an unsealed condition at 40–150°C confirmed the formation of the geopolymer network. Coatings cured at 80°C possessed a favorable microstructure, while some microcracks were present in the coatings after curing at 150°C due to shrinkage and residual stresses.

Measured adhesion strength

The adhesion strength, measured by scratch tests, showed high values of critical load for samples cured at 80°C. For samples cured at 150°C, the coating was completely removed upon loading when the geopolymer was deposited on Al but not when on mild steel. Immersion tests demonstrated that the stability of the coatings in distilled water increased with increasing curing temperature.

The study has been published in Journal of Coatings Technology and Research volume 17 (2020).

Related content

More innovations on protecting metallic surfaces with coatings can be found at the European Coatings Supplier's hub. At the moment 12 video presentations and 2 technical documents present novel technologies and products that can help formulators to design novel and high quality protective coatings.

top of page
Comments (0)
Add Comment

Post comment

You are not logged in

register