OLANDIR VERCINO CORREA

OLANDIR VERCINO CORREA

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Coatings to protect spent aluminium-clad research reactor fuel during extended wet storage
2017 - FERNANDES, S.M.C.; CORREA, O.V.; SOUZA, J.A. de; RAMANATHAN, L.V.; ANTUNES, R.A.; OLIVEIRA, M.C.L. de
Conversion coatings have been used to protect aluminium surfaces from corroding. Hence use of this type of coating was considered to protect the aluminium cladding of spent research reactor fuels during extended wet storage. A conventional chemical process, as opposed to an electrochemical process, is preferred due to the shape of the fuel and its high radioactivity. In this context hydrotalcite (HTC) and boehmite coatings were considered. This paper presents the results of further development of HTC coatings, from the stand point of eventually being able to coat highly radioactive spent fuels using remote handling equipment. More specifically: (a) preparation of HTC coatings from different baths on AA 6061 alloy surfaces that were given pre-treatments to simulate spent fuel surfaces; (b) characteristics of the HTC coatings as a function of bath temperature; (c) corrosion behaviour of HTC coated AA 6061 alloy; (d) results of field studies in which dummy fuel elements, consisting of Al alloy plates coated with HTC from different baths (with or without post coating treatments), were immersed in the IEA-R1 reactor’s spent fuel basin for periods of up to 2 years. This study demonstrates that Al surfaces can be coated with HTC using an allroom temperature process. The field tests revealed marked increase in corrosion resistance of HTC coated plates. The mechanism of corrosion protection is discussed and a mock-up arrangement to remotely handle dummy-fuel elements to pre-treat, coat with HTC and post-treat is presented.
Hydrotalcite coatings to protect spent sluminum-clad nuclear fuels during long term wet storage
2015 - FERNANDES, S.M.C.; CORREA, O.V.; SOUZA, J.A. de; ANTUNES, R.A.; OLIVEIRA, M.C.L. de; RAMANATHAN, L.V.
Pitting corrosion of the aluminium cladding of spent research reactor (RR) fuels in wet storage has been reported and attributed to synergistic influence of certain water parameters. Hence, use of conversion coatings to protect spent Al-clad RR fuel during long term wet storage was proposed. The objective was to develop a coating using a conventional chemical process as opposed to an electrochemical process due to constraints related to the shape of the fuel and its high radioactivity. In this context hydrotalcite (HTC) and boehmite were considered. This paper presents: (a) preparation of boehmite and hydrotalcite (HTC) coatings from different baths followed by post-coating treatments; (b) corrosion behavior of coated AA 6061 alloy; (c) results of field studies in which uncoated and coated AA 6061 alloy coupons and plates, the latter assembled as a dummy fuel element, were exposed to the IEA-R1 reactor spent fuel basin for periods of up to 14 months. The laboratory tests revealed marked increase in corrosion resistance of HTC coated specimens. In field tests the HTC coated coupons and plates did not reveal any pits. The mechanism of corrosion protection is presented.
Coatings to protect spent aluminium-clad research reactor fuel during wet storage
2015 - FERNANDES, S.M.C.; CORREA, O.V.; SOUZA, J.A. de; RAMANATHAN, L.V.; ANTUNES, R.A.; OLIVIERA, M.C.L. de
Lanthanide based conversion coatings for long term wet storage of aluminium-clad spent fuel
2010 - FERNANDES, S.M.C.; CORREA, O.V.; SOUZA, J.A. de; RAMANATHAN, L.V.
Spent fuels from research reactors are stored in basins with water of less than desirable quality at many facilities around the world and instances of cladding failure caused by pitting corrosion have been reported. Conversion coatings have been used in many industries to protect different metals, including aluminium alloys. This paper presents the results of an ongoing investigation in which the corrosion resistance of lanthanide (cerium, lanthanum and praseodymium) based conversion coated RR fuel cladding alloys has been studied. Electrochemical tests in the laboratory revealed higher corrosion resistance of CeO2, La2O3 and Pr2O3 coated AA 1100 and AA 6061 alloys in NaCl solutions. Uncoated and CeO2 coated coupons of these alloys exposed for 50 days to the spent fuel basin of the IEA-R1 research reactor in IPEN, Brazil, revealed marked reductions in the extent of pitting corrosion.
Conversion coatings to protect spent nuclear fuel during extended wet storage
2012 - FERNANDES, S.M.C.; CORREA, O.V.; SOUZA, J.A. de; RAMANATHAN, L.V.
Coatings for increased corrosion resistance of aluminium-clad spent fuel in wet storage
2012 - FERNANDES, S.M.C.; CORREA, O.V.; SOUZA, J.A. de; RAMANATHAN, L.V.
Hydrotalcite coatings for increased aqueous corrosion resistance of aluminium alloys
2012 - FERNANDES, S.M.C.; CORREA, O.V.; SOUZA, J.A. de; LIMA, N.B. de; SILVA, F.R.O.; RAMANATHAN, L.V.
Coatings for increased protection of aluminium clad spent nuclear fuel during long term wet storage
2013 - FERNANDES, S.M.C.; CORREA, O.V.; SOUZA, J.A. de; LIMA, N.B. de; RAMANATHAN, L.V.; ANTUNES, R.A.; OLIVEIRA, M.C.L. de
Conversion coatings to protect Al-CLAD spent fuel in wet storage
2013 - FERNANDES, S.M.C.; CORREA, O.V.; SOUZA, J.A. de; LIMA, N.B. de; RAMANATHAN, L.V.; ANTUNES, R.A.; OLIVEIRA, M.C.L. de
A coating to protect spent aluminium-clad research reactor fuel assemblies during extended wet storage
2009 - FERNANDES, S.M.C.; CORREA, O.V.; SOUZA, J.A. de; RAMANATHAN, L.V.