Jet engines wouldn't run without high-performance coatings - BBC Technology Reporter Chris Baraniuk reports.
Jet engines exemplify incredible engineering, yet their functionality is challenged by extreme heat. Ben Beake, Director at Micro Materials, highlights that the air entering jet engines exceeds the melting point of metals used in the blades, reaching over 1,000°C. To counter this, designers employ heat-resistant ceramic coatings, and advancements in stronger coatings could lead to significant fuel and CO2 savings.
Coatings significantly enhance the performance and durability of materials, often going unnoticed despite their critical role in high-performance machinery. At Micro Materials, researchers continuously assess the limits of these coatings, utilizing a “woodpecker” device that tests durability through repeated impacts.
Recent collaborations with Teer Coatings focus on protective coatings for satellite components, ensuring they withstand atmospheric humidity on Earth and hazards in space. These coatings might also combat biofilms, which can compromise water supplies and machinery on spacecraft.
Kripa Varanasi at MIT has created super-slippery coatings that resist biofilm formation, demonstrating efficacy during testing aboard the International Space Station.
Nuria Espallargas at the Norwegian University of Science and Technology has developed a silicon carbide-based coating for aluminium manufacturing, preventing molten aluminium from sticking and extending tool lifespan, thus reducing costs dramatically.
Despite their advantages, coatings can sometimes fail. Managing Director Andy Hopkinson from Safinah Group notes issues with passive fire protection systems in car parks and biofouling on ships leading to increased fuel consumption. Safinah Group is a firm that often gets called in to investigate when coatings go wrong.
“The shipping is always interested in coatings that can keep hulls cleaner.
Coatings can do some amazing things, but they don’t always work as intended”“We’re seeing a lot of issues at the moment with car parks, where their passive fire protection system is peeling off,” he says, referring to the fire-resistant paint sometimes applied to concrete structures.
And his company (Safinah) has also found that coatings applied to commercial ships do not always prevent barnacles and other sea life from attaching themselves to the hull. This problem, known as biofouling, increases friction, meaning the ship’s engine must work harder, external – and burn more fuel.
“Despite the availability of coatings that promise to help, ship owners do not always choose the correct one for their vessel. That choice should depend on where the ship is sailing, how long it is due to be idle rather than in motion, and so on”, says Dr. Hopkinson.
The cost of fixing issues like this can run into many thousands, or even millions of pounds. “Typically, paint costs between 1 and 2% of the project. The problem is, when it goes wrong, the costs become exponential.”
While challenges remain, opportunities to refine and innovate coatings promise to enhance machinery performance and infrastructure durability in the future.
Read the full article – https://www.bbc.co.uk/news/articles/cj9n1939ryzo
