Nov, 2021 - By WMR
Scientists developed a novel coating from sulfur-selenium alloy that efficiently protects steel from corroding and heals itself in two minutes.
A team of scientists from Rice University, Houston, Texas developed a novel alloy with unique and different qualities that makes it more efficient to prevent corrosion of steel. According to the research published in the journal Advanced Material on October 15, 2021, the new coating not just prevents rusting of common steel, it also possesses capability of healing itself when it is damaged.
The scientists built this novel anti-corrosion coating from a lightweight sulfur-selenium alloy, which combines finest qualities of inorganic coatings like chromium and zinc-based materials that block chorine ions and moisture, however not the coatings that prevent steel from corrosion. To establish this, the team conducted some experiments, where they put small slabs of normal mild steel with sulfur-selenium alloy coating, and a steel slab without any coating as a control in seawater for a period of month. The scientists found that the steel with coating had no change in colour, while the steel without coating rusted radically, which proved that the coated steel has high resistance to oxidation. Furthermore, the team tested these steels against sulphate-reducing bacteria that generally fastens the corrosion process. When exposed to biofilms and plankton, the coated steel again proved to be oxidation resistant.
As per the researchers, sulfur-selenium alloy coating poses an “inhibition efficiency” of 99.99%. The team at last tested the self-healing property of the alloy by slicing a film in half and putting it on a hotplate next to each other. It resulted into reconnecting of parts in 2 minutes when it was heated to 158˚F (70˚C) and having same flexibility as the original film. When these films were heated at 266˚F for 15 minutes, it also healed the pinhole defects in it. According to the scientists, the novel alloy could not just serve as a protective coating, it could be used in flexible electronics too.