Resumo de eventos cient??ficos
Effect of processing parameters on hydrotalcite (HTC) coating microstructure and the corrosion behavior of HTC coated AA 6061 alloy
Autor
RAMANATHAN, L.V.
FERNANDES, S.C.
CORREA, O.V.
SOUZA, J.A.B.
ANTUNES, R.A.
LIMA, N.B.
CONGRESSO BRASILEIRO DE ENGENHARIA E CI??NCIA DOS MATERIAIS, 23.
Resumen
Pitting corrosion of the aluminium cladding of spent nuclear fuels stored in light water
pools has been observed. To prevent this, coating of the Al cladding with hydrotalcite
(HTC) was proposed. This paper presents the effect of various processing parameters
on HTC microstructure and the corrosion behavior of HTC coated AA 6061 specimens.
The HTC coating from the high temperature nitrate bath was homogeneous, thicker
and consisted of well-defined intersecting platelets than that formed from the room
temperature carbonate bath. Electrochemical polarization measurements as well as
long term exposure to aggressive aqueous media of HTC coated AA 6061 specimens
revealed that specimens coated with HTC from the nitrate bath and further treated in
a cerium salt solution were the most resistant to corrosion. The mechanism by which
the HTC coating and cerium protect the Al alloy is discussed.