Synthesis and characterisation of high-entropy alloy thin films as candidates for coating nuclear fuel cladding alloys

Abstract

HighlightsIon beam sputter-deposition was used to produce thin films from the system FeCrMnNi.Two thin films were obtained at same deposition conditions. The high-entropy alloy thin film exhibited grains with sizes around 100 -200 nm.The non-equiatomic thin film exhibited grains with sizes around of 40 nm.High-entropy alloy and nucleation theories are used to reflect on the results. AbstractThin films of the quaternary system FeCrMnNi were synthesised by ion beam sputterdeposition. The films were deposited on a silicon substrate at approximately 350 K. A highentropy alloy thin film (HEATF) and a non-equiatomic thin film were obtained. Energy Dispersive X-Ray Spectroscopy (EDX) and Transmission Electron Microscopy (TEM) were used to determine thin film composition and the atomic structure. The non-equiatomic thin film exhibited a polycrystalline structure with nanometre-sized. Microstructural analysis of the HEATF, which had close to equimolar composition, showed large crystals and planar defects. The microstructural differences between the HEATF and the non-equiatomic thin film are discussed in terms of current high-entropy alloy theory, previous work on thin films and nucleation theory.

Energetic particle irradiation study of TiN coatings: are these films appropriate for accident tolerant fuels?

“…In order to reduce or possibly suppress the RIS effect, MAX Phases [43] and High-Entropy Alloys [44,45] should be taken into consideration for future radiation damage and tribology studies on coating Zr-based alloys for the nuclear industry. The intense recent research on these materials have indicated a potential high phase stability under energetic particle bombardment when compared with conventional ceramic materials and metallic alloys, and this could imply -from a microstructural perspective -a superior tolerance against the multiple deleterious effects of energetic particle irradiation [43,45].…”

High-Entropy Alloys for Advanced Nuclear Applications

“…A useful lookup tool for the neutron scattering and capture cross sections for elements as a function of neutron energy is the TENDL nuclear data library [ 27 ]. A number of studies have used low neutron cross section elements to design HEAs for ATF cladding, either as bulk alloys [ 28 , 29 , 30 , 31 ] or as coatings for Zr alloys [ 32 , 33 , 34 , 35 , 36 ]. Preliminary results of the HEA coatings has suggested better wear and corrosion performance than uncoated Zr, and authors have claimed they are good candidates for ATF cladding [ 33 , 34 ].…”

Oxidation behavior of Cr-coated zirconium alloy cladding in high-temperature steam above 1200 °C

“…Compared with other ATF candidate claddings, the coated Zr alloy is the easiest and most economic approach, which is supposed to the near-term choice for ATF cladding application. Some coating materials have been investigated, including pure metals [17][18][19][20] , alloys [21][22][23] , ceramics 24,25 , and MAX phases 8,26 , among which, the metallic Cr coatings exhibit good resistance to oxidation in both normal condition and accident condition (e.g., LOCA) 6,[17][18][19][20] . This has boosted extensive studies on the Cr-coated Zr alloy cladding during the last decade.…”