Safer, low-cost nuclear material storage through cold spray-formed boron carbide-coated components
Acronym: SafeStore
Funding body: Innovate UK
Status: Completed
Safer, low-cost nuclear material storage through cold spray-formed boron carbide coated components (SafeStore)Transport and/or storage of spent nuclear fuel can require neutron shielding materials. Two such materials currently used are composite plate materials consisting of aluminium (or aluminium alloys) containing varying proportions of boron carbide particulates, which have a high neutron absorbing capability. Whilst these metal matrix composite (MMC) materials are suitable for specific niche applications, the current manufacturing route is unable to produce them in anything other than flat solid plates. This limits the design options for containers/canisters.In the SafeStore project, cold spray coating technology was used to develop a material that is similar to the MMC but can be applied to sheet metal fabrications in any desired thickness up to tens of millimetres. Cold spray technology facilitates the co-deposition of thermally sensitive and/or easily oxidised materials such as Al and B4C without thermal degradation. The coatings were developed and applied to steel samples and plates and the deposition parameters were then further improved to obtain higher levels of B4C in the coatings.The use of a coating results in better design flexibility and hence better and more cost-effective dry cask storage options. The project was led by Graham Engineering, a UK-based company with a strong track record in the supply of nuclear waste fuel containers. TWI conducted the coatings development work whilst Graham Engineering helped define the market needs and facilitated the characterisation and evaluation of the radiological performance of the coatings.