Supersonic Particle Deposition for the Application of a Bimetallic Corrosion Resistant Layer in Nuclear Components

The problem being addressed is the expected shortfall in electrical power generation due to decreased supply and increased demand. Many coal-fired power plants are reaching the end of their life and are unlikely to be replaced by new coal fired plants due to emissions. Electrical power demand is expected to increase steadily through year 2050 due to population growth and increased electric vehicle popularity. Natural gas power plants can cover some of this shortfall, but long-term natural gas prices are unknown. The US Department of Energy and other parties are looking to small modular nuclear reactors (SMRs) for a solution. They are designed to be inherently safer and less expensive to build and operate than older nuclear power. They can also do “double duty” by providing process heat for desalination of seawater, manufacture of hydrogen gas, biofuel production, and many others. Cold spray, a solid-state materials deposition technology, will be used to apply robust corrosion-protective coatings on SMR components. This will let many components be made of carbon steel, a less expensive and easier to use material than stainless steels and other high-performance alloys. Cold Spray can apply many different metals onto carbon steel, such as pure nickel, pure titanium, or Inconel 625, to provide excellent corrosion protection that tolerates high temperatures. In Phase I, these materials were successfully deposited onto A516 carbon steel. In Phase II the corrosion behaviors of those coatings have been tested, high-temperature “non-stick” nozzles have been developed to allow deposition of these materials at high process gas temperatures and long durations without clogging or wearing out. A modular and flexible system to apply these coatings on an industrial scale has also been developed and built that can operate multiple powder feeders in parallel or in sequence as desired. This allows lengthy sprays by seamlessly switching from an almost empty feeder to a full one, and refilling the almost empty one. Feeding simultaneously can facilitate very high deposition rates. In Phase IIB the developments in Phase II will be thoroughly tested and vetted for commercial deployment in industrial settings. The system and nozzles will be operated at lengthy intervals to identify and correct any issues that prevent successful industrial deployment. The nonstick nozzles will also be redesigned for faster and more economical materials deposition. A thoroughly vetted cold spray system for industrial scales will help make and maintain SMRs economically, which will provide reasonably-priced carbon-free electrical power. The system will be suitable for many other industries as well, including traditional nuclear power, wind power, biofuels, and many others. Five commercial actors have submitted letters of support for these developments, and will provide initial sales upon completion.