000 01995nab a2200205 4500
005 20260520000949.0
008 260224s2010 xxu
245 0 0 _aCharacterizing the relaxation of the open-circuit potential during an AC-DC-AC accelerated test
260 _a
_b
_csep. 2010
270 _a13/09/2010 ; 13/09/2010
300 _a11 p. ; 095001
520 _aTranscripción del resumen del autor. The non-conventional accelerated alternating current-direct current-alternating current (AC-DC-AC) testing method for organic coatings induces degradation by promoting cathodic reactions at the metal coating interface and ionic transport in the bulk of the coating. This cyclic method involves a testing step in which the coating properties are determined using electrochemical impedance spectroscopy (EIS), a DC step in which a cathodic potential is applied for a given time period, and a relaxation step where the coating is allowed to relax back to a stable open-circuit potential (EOC) condition. Analysis of the relaxation EOC profile has been reported where characteristic times were attributed to the transport of ions through the coating, dielectric relaxation of the coating, and charge transfer at the metal/coating interface. The AC-DC-AC degradation of a standard United States Army vehicle epoxy primer on a steel substrate is reported here. The influences of applied DC potential and temperature were determined by subjecting the coating to potentials of -2 V and -8 V relative to the stable EOC at temperatures ranging from 25°C to 65°C. The relaxation EOC profiles were analyzed with a mathematical model to yield the characteristic times associated with the processes involved and the consistency of these processes with Arrhenius behavior was determined.
581 _a9
773 0 _tCorrosion
_g66
942 _cARTICULO
100 1 _aAllahar, K.N.
_940322
100 1 _aUpadhyay, V.
_946835
100 1 _aBierwagen, G.P.
_943352
999 _c176894
_d176894