Science

Coating against corrosion

Name: Mina Abdolahzadeh (29)
Nationality: Iran
Supervisors: Dr. Santiago Garcia and prof.d

r.ir. Sybrand van der Zwaag (Aerospace Engineering, Novel Aerospace Materials Group)

Subject: Development of intrinsic healing sol-gel based on anti-corrosion coatings

Thesis Defence: In 2.5 years


“Corrosion affects materials daily and this could lead to severe damage. For example damage to parts of a car or plane could have grave consequences. Application of protective coatings is one of the most efficient methods for preventing corrosion of metallic substrates. However just like other engineering materials, coatings fail to fulfil their functionalities over time due to damage or degradation. Therefore development of coatings capable of repairing the damage is highly valuable. Currently, I am developing a self-healing anti-corrosion coating.

Generally there are two classes of self-healing materials: extrinsic and intrinsic systems. In extrinsic systems, such as capsule based systems, the healing agents are added as a separate phase. However, intrinsic systems, such as hydrogen-bonded systems, possess a latent self-healing functionality due to the architecture of the molecules themselves.

I have focused on intrinsic healing approaches as they work multiple times and can be triggered by various stimuli such as moisture or temperature to recover their main functionality.

In the 1.5 years that I spent in the laboratory, I have developed the first family of intrinsic healing coating for metallic substrates using sol-gel chemistry. This is a wet-chemical technique that is often used in the field of material science.

Apart from synthesis, I characterized the thermal and mechanical properties of developed systems using different techniques. For example I examined the adhesive healing of the coatings by gluing two metal plates together using my coating system and then sliding the samples until they fail. Then I glued them back and re-did the experiment at least five times. So far, I am happy with the results and feel my work is heading in the right direction.

I also do an experiment to test cohesive healing. I cut the coating into two pieces and put them, 500 micrometres apart, between two glass plates in the oven. For the developed system the gap closes and the coating repairs itself most efficiently at a temperature of 70 degrees.

I do not only want to find a coating that repairs itself but I would also like to understand how the mechanism of self-healing works. Hopefully my research could help significantly to make self-healing coating work as well as making airplanes and cars safer and reducing maintenance costs.”

Editor Redactie

Do you have a question or comment about this article?

delta@tudelft.nl

Comments are closed.