Revolutionary Al-Mg-Si coating invented by scientists to curb corrosion on steel

Scientists have derived an innovative method of coating steel surfaces with different metals such as aluminium (Al) to enhance corrosion resistance. But its tendency to react with chloride ions in seawater makes use of pure aluminium impossible. Therefore, the addition of other elements, such as magnesium (Mg) and silicon (Si) to form an aluminium alloy is a promising way around this problem. But Mg isn’t friendly enough to coat itself on any metal just after the latter is dipped into a hot bath of metal salts.

In reference to the study published in Corrosion Science, a new concord for Al-Mg-Si coating of steel has been developed.

Professor Myeong-Hoon Lee who guided the study said, "When I served in the navy, I was constantly looking at rusting machinery. Since then, I have become fully engaged in research on how to produce better anti-corrosive steels.”

However, this study was made available online on 9^th September 2021 and was published in volume 192 of the journal in November 2021.

To conclude this study the researchers took aluminized steel (Ai and S1) platting it with Mg, a method known as ‘physical vapour disposition. Then the coating was exposed to a temperature of 375°C. They did also segregate the coating film and perform corrosion testing in form of a “salt spray test”. As per their findings, two layers of coating would be easily distinguishable, the first being that of aluminium on top while in the inner layer, a mixture of Al-Mg-Si based products can be found. The inner layer of these corrosion products also provides a ‘shielding effect’, further improving their anti-corrosion discography.

Professor Lee teaches at Korea Maritime and Ocean University and also chairs the Centre of Surface Corrosion Control (Engineering) exemplified, "Our research reveals how highly corrosion-resistant steel can be produced using a simple change in the surface treatment protocol. This makes it very meaningful for conserving energy and environmental resources.”