Transition metal nitride films have a unique combination of properties and finds application as protective coatings. The present paper deals with the degradation behaviour of HfN coating deposited by reactive magnetron sputtering on high-density (HD) graphite and niobium (Nb) crucibles with molten uranium. Uranium melting experiments were carried out with uranium shots placed in HfN-coated crucibles and heated to 1573 K under ultra high purity argon gas for 25 min. The study showed delamination of HfN coating deposited on Nb and HD graphite crucibles. The degradation of HfN-coated niobium was attributed to partial melting and surface oxidation. Uranium melting of HfN-coated HD graphite crucible led to coating spallation that could be attributed to thermal expansion mismatch and also resulted in the formation of uranium–carbon mixture of unusual morphology. The paper highlights the results of the present investigation.
BrunsvoldAR, RoachPD, WestphalBR.Design and development of a cathode processor for electrometallurgical treatment of spent nuclear fuel. Proceedings of 8th International Conference on Nuclear Engineering (ICONE 8); 2000 Apr 2–6; Baltimore, MD, USA. p. 1–9. (Paper no: ICONE-8702)
2.
WestphalBR, MarsdenKC, PriceJC, On the development of a distillation process for the electrometallurgical treatment of irradiated spent nuclear fuel. Nucl Eng Technol. 2008;40:163–174. doi: 10.5516/NET.2008.40.3.163
3.
WestphalBR, MarsdenKC, PriceJC.Development of a ceramic-lined crucible for the separation of salt from uranium. Metall Mater Trans A. 2009;40:2861–2866. doi: 10.1007/s11661-009-9957-3
4.
PiersonHO.Hand book of refractory carbides and nitrides: the refractory nitrides, properties, characteristics, processing and applications. Westwood (NJ
): Noyes Publications; 1996. p. 181–191.
5.
VasconcelosGD, DacalLCO, SbampatoME, Titanium nitride: a key to process metallic uranium. Phys Stat Sol. 2004;201(10):2351–2355. doi: 10.1002/pssa.200304919
6.
JangJ, LeeH-S, LeeS.Stability of plasma-sprayed TiN and ZrN coatings on graphite for application to uranium-melting crucibles for pyroprocessing. J Radioanal Nucl Chem. 2016;310:1173–1180. doi: 10.1007/s10967-016-4947-6
7.
Ravi ShankarA, Prabhakara ReddyB, ChawlaV, Characterization of nitride coatings on high density graphite deposited by magnetron sputtering. Surf Coat Technol. 2010;204:3214–3221. doi: 10.1016/j.surfcoat.2010.03.019
8.
HuangJS, GallegosGF.Embrittlement by liquid U in some group VB and VIB metals and alloys during tensile loading at 1473 K. Metall Trans A. 1990;21:1959–1967. doi: 10.1007/BF02647244
9.
RickerbyDS, MatthewsA.Handbook of surface engineering: advanced surface coatings. Chapman and Hall; 1991. p. 92–123.
10.
KellyPJ, ArnellRD.Magnetron sputtering: a review of recent developments and applications. Vacuum. 2000;56:159–172. doi: 10.1016/S0042-207X(99)00189-X
11.
OakesJJ.A comparative evaluation of HfN, Al2O3, TiC and TiN coatings on cemented carbide tools. Thin Solid Films. 1983;107:159–165. doi: 10.1016/0040-6090(83)90018-4
12.
Ravi ShankarA, Kamachi MudaliU, ChawlaV, Magnetron sputter deposition of hafnium nitride coating on high density graphite and niobium substrates. Ceram Int. 2013;39(5):5175–5184. doi: 10.1016/j.ceramint.2012.12.014
13.
Thermal properties of metals. Materials Park (OH
): ASM International; 2002, p. 11.
14.
PeriasamyP, HurleyMF, MarxBM, Compatibility of ZrN and HfN with molten LiCl–KCl–NaCl–UCl3. J Nucl Mater. 2010;405:266–273. doi: 10.1016/j.jnucmat.2010.08.015
15.
ChenPS, StevensWC, TrybusCL.Reusable molds for casting U-Zr alloys. Paper submitted to the Sixth International Conference on Surface Modification Technology; 1992 Nov 1–5; Chicago (IL). (ANL Report: ANL/FE/CP-75641, 1992 Sep).
16.
NagarajA, MukherjeeJ, AnupamaP, Liquid uranium corrosion studies of protective yttria coatings on tantalum substrate. J Nucl Mater. 2011;410:39–45. doi: 10.1016/j.jnucmat.2010.12.307
17.
Jagadeeswara RaoC, Ravi ShankarA, MallikaC, Performance evaluation of plasma sprayed yttria coatings on high density graphite for cathode processor applications. Ceram Int. 2015;41(2):3128–3136. doi: 10.1016/j.ceramint.2014.10.157
18.
ChoC-H, LeeY-S, KimE-S, The reactivity with uranium of coating layers by the thermal spraying method. J Radioanal Nucl Chem. 2011;287:485–490. doi: 10.1007/s10967-010-0805-0
19.
HongK-W, KimK-H, HongS-I.Application of ceramic plasma-spray coatings for reusable melting crucible of U-10wt.%Zr-5wt.%RE metallic fuel. Paper submitted to the Sixth Asia-Pacific Symposium on Radiochemistry; 2017 Sep 17–22; Jeju Island, Korea.
20.
KimJH, KimHT, KimKH, Interaction phenomena between ceramic coatings and liquid uranium alloys. J Radioanal Nucl Chem. 2014;300:1245–1251. doi: 10.1007/s10967-014-3086-1
21.
HolcombeCE, BankerJG.Uranium/ceramic oxide and carbon/ceramic oxide interaction studies. Metall Trans B. 1978;9:317–319. doi: 10.1007/BF02653700
22.
IizukaM, AkagiM, KoyamaT.High-temperature distillation and consolidation of U–Zr cathode product from molten salt electrorefining of simulated metallic fuel. J Nucl Mater. 2014;448:259–269. doi: 10.1016/j.jnucmat.2014.02.015
