OLANDIR VERCINO CORREA
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Artigo IPEN-doc 23608 Preparation and characterization of hydrotalcite coatings to protect aluminium alloys2016 - FERNANDES, S.M.C.; CORREA, O.V.; SOUZA, J.A.; ANTUNES, R.A.; LIMA, N.B. de; RAMANATHAN, L.V.Pitting corrosion of the aluminium alloy cladding of spent research reactor fuels during wet storage is the main form of degradation. To prevent this, hydrotalcite (HTC) based coatings were proposed. This paper presents the effect of chemical bath parameters on the microstructure of HTC coatings and the corrosion behavior of HTC coated AA 6061 specimens. The HTC coating formed at 98 °C from nitrate baths and referred to as HT-HTC was homogeneous and consisted of intersecting blade-like crystallites. Electrochemical tests revealed that HT-HTC coated specimens that were treated in a cerium salt solution were the most resistant to corrosion. Field tests in which un-coated and HTC coated AA 6061 alloy coupons as well as full-size plates were exposed to the IEA-R1 reactor’s spent fuel basin for 23 months corroborated the high corrosion resistance imparted by the HT-HTC + Ce coating. The mechanism by which the HTC coating and cerium protect the Al alloy is discussed.Artigo IPEN-doc 20477 Effect of sol-gel preparation technique of mixed nanocrystalline rare earth oxide coatings on high temperature oxidation behavior of Fesup(2)0Cr5al alloy2014 - FERNANDES, S.M.C.; CORREA, O.V.; RAMANATHAN, L.V.Resumo IPEN-doc 19754 Nanostructured coatings to protect metallic materials at high temperatures2013 - FERNANDES, S.M.C.; PILLIS, M.F.; CUNHA, C.A.; CORREA, O.V.; RAMANATHAN, L.V.Resumo IPEN-doc 13317 Effect of temperature and erodent velocity on erosion-oxidation behaviouir of steels AISI 1020, 410, 304 and 3102008 - FERNANDES, S.M.C.; CORREA, O.V.; RAMANATHAN, L.V.Resumo IPEN-doc 12585 Cyclic oxidation resistance of rare earth oxide gel coated Fe-Cr alloys2006 - FERNANDES, S.M.C.; CORREA, O.V.; RAMANATHAN, L.V.Use of rare earths to increase high temperature oxidation resistance of chromium dioxide and alumina forming alloys is well known. Rare earth oxide coatings obtained by the solgel technique have been found to be very efficient to apply fine oxide coatings. The cyclic oxidation resistance (RT-900ºC) of Fe-Cr alloy coated with various rare earth oxide gel coatings (La2O3, CeO2, Pr2O3, Nd2O3, Sm2O3, Gd2O3, Dy2O3, Y2O3, Er2O3, and Yb2O3) was determined. Specimens coated with La2O3 and Pr2O3 gels were found to be the most resistant to cyclic oxidation. In an extension of this study, the effect of cooling rate, (and consequently thermal shock resistance) from the peak temperature (900ºC, 1000ºC, 1100ºC) to room temperature of specimens coated with La2O3 and Pr2O3 gels was studied. The morphology and coverage of the rare earth oxide gels varied with the type of rare earth. The cyclic oxidation resistance increased with increase in time at temperature required to reach a specific chromium dioxide layer thickness. This in turn was influenced by rare earth ion radius and other characteristics of the rare earth oxide coating such as morphology, stability, coverage, resistance to thermal stresses and adhesion.Artigo IPEN-doc 15881 Effect of mixed rare earth oxide coatings on high temperature oxidation of Fe-20Cr alloy2010 - FERNANDES, S.M.C.; CORREA, O.V.; RAMANATHAN, L.V.Artigo IPEN-doc 10517 Effect of coupon orientation on corrosion behavior of aluminium alloy coupons in the spent fuel storage section of the IEA-R1 research reactor2004 - CORREA, O.V.; LOBO, R.M.; FERNANDES, S.M.C.; MARCONDES, G.; RAMANATHAN, L.V.Artigo IPEN-doc 18404 Hydrotalcite coatings for increased aqueous corrosion resistance of aluminium alloys2012 - FERNANDES, S.M.C.; CORREA, O.V.; SOUZA, J.A. de; LIMA, N.B. de; SILVA, F.R.O.; RAMANATHAN, L.V.Artigo IPEN-doc 14384 High temperature erosion-oxidation behavior of steels2007 - FERNANDES, S.M.C.; CORREA, O.V.; RAMANATHAN, L.V.Artigo IPEN-doc 02865 Corrosao e caracterizacao microestrutural de ligas inconel 600 nacional e importada1995 - CORREA, O.V.; FERNANDES, S.M.C.; SOUZA, J.A.B.