Layer Protecting the Surface of Zirconium Used in Nuclear Reactors
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2016-03-22 |
| Journal | Recent Patents on Nanotechnology |
| Authors | Petr Ashcheulov, Radek Ĺ koda, Jan Ĺ karohlĂd, Andrew Taylor, F. Fendrych |
| Institutions | Czech Academy of Sciences, Institute of Physics, Czech Academy of Sciences |
| Citations | 8 |
Abstract
Section titled âAbstractâZirconium alloys nuclear fuel pinsâ surfaces were covered by compact and homogeneous polycrystalline diamond layers consisting of sp(3) and sp(2) carbon phases with a high crystalline diamond content and low roughness. Diamond withstands very high temperatures, has excellent thermal conductivity and low chemical reactivity, it does not degrade over time and (important for the nuclear fuel cladding) being pure carbon, it has perfect neutron cross-section properties. Moreover, polycrystalline diamond layers consisting of crystalline (sp(3)) and amorphous (sp(2)) carbon phases could have suitable thermal expansion. Zirconium alloys coated with polycrystalline diamond film are protected against undesirable changes and processes. Further, the polycrystalline diamond layer prevents the reaction between the alloy surface and water vapor. During such reaction, water molecules dissociate and initiate formation of zirconium dioxide and hydrogen, accompanied by the release of large amount of heat. Thus the protective layer prevents the formation of hydrogen and the release of reaction heat. Few relevant patents to the topic have been reviewed and cited.