A nanotechnology materials firm, Powdermet, proposed a spray-on form of various cermet coatings able to withstand such temperatures. Cermets (ceramic/metal alloys) are used in the very high temperature solar thermochemical reactors designed to manufacture solar fuels at 1000ºC and above, but these nickel-based superalloys are very costly and if used for all the piping and storage system throughout an entire CSP plant would fail the cost requirement. "So the whole idea of using the cermet as a coating is to reduce the cost," Cardenas explained. "There is availability of high temperature materials that will resist the corrosion of the salt, specially up to higher temperatures. But the problem is they start to get very expensive, so then you would use something that's maybe a little more price friendly like stainless steel 316 and coat it with the cermet." Tests showed that coatings of Cermet NiWC3b had better corrosion protection than the metal or cermet alloys alone. This nanotech material would be sprayed on by high velocity, oxy-fuel thermal spray coating on the base alloy.
