Expert team develops self-healing anti-rust coating

Scientists have created a coating made from a sulfur-selenium compound that can protect steel in seawater and self-heal when cut or punctured.

A team of experts at Rice University (USA) created a new compound with many unique properties , bringing high efficiency in protecting steel from corrosion, New Atlas on October 19 reported. The compound can be used as a rust-preventive coating for steel bars placed under water, and is also very flexible, malleable and can self-heal when damaged.

Scientists at Rice University coated steel with a new compound to prevent corrosion. (Photo: Jeff Fitlow/Rice University)

The new coating is made of a mild sulfur-selenium compound and combines the properties scientists wanted. It has the same moisture and chlorine resistance as zinc and chromium-based coatings, protects steel in seawater-like environments like polymer-based coatings, and is also resistant to microbial corrosion. object.

The team determined these properties through a series of experiments. First, they soaked mild steel bars coated with sulfur-selenium compounds in seawater with uncoated steel for about a month. While plain steel rusts severely, coated steel does not change color, exhibiting good oxidation resistance.

Next, they experimented with sulfate-reducing bacteria , which are thought to dramatically accelerate the corrosion process. They exposed coated and uncoated samples to plankton and biofilm. This time, the coating continues to help protect the steel. According to the research team, the coating provides an inhibitory effect of up to 99.99%.

The most impressive ability the team discovered is perhaps powerful self-healing. When a composite film is cut in half and placed side-by-side on a hot plate, they recombine into a film within two minutes when heated to 70 degrees Celsius. Perforations can also be repaired by heating to 130 degrees Celsius for 15 minutes. The material after healing also gives the same good protection of the steel as the original, when intact.

"If the compound is punctured, it will recover. If a quick recovery is needed, we will assist with the use of heat. However, most thick samples will recover on their own over time," said Muhammad Rahman, a member of the team. research team member, said.

With its flexible properties, the new compound is not only suitable for protecting steel in water, but also for bendable electronic devices. The team of experts say that the new compound is a better insulator than most flexible materials, and is more flexible than most insulators. They are further experimenting with versions of the new material to suit different steels and exploring different coating techniques. The study was published in the journal Advanced Materials.