Resistance Values of Aluminum Oxide Film in Situ during Anodization of Aluminum by Fabry-Pérot Interferometry

Novel Electrochemical-Emission Spectroscopy of Metals by White Light Interferometry

“…as a constant or an initial boundary. In contrast, because the initial anodization was not exactly defined, i.e., when J(t)> 0, mA/cm 2 , therefore, determining the current density rate d(J)/dt, 1 st derivative of J with respect to t, is not possible between an open interval of; ]J(0),J (10)]. As a result, the current density rate of the oxide films was estimated to be 0 at 10 mins.in all cases due to the 1st derivative of an assumed constant d(10)/dt is zero.…”

“…J is the anodic current density (mA/cm 2 ) of the oxide film, F is Faraday's constant, |Z| is absolute number of electron charge, M is the atomic weight of based metal (kg), T is the time of anodic reaction (sec), 90mins. D is the density of the base metal (g/cm 3 ), d is thickness of the oxide film which can be obtained by Fabry-Perot interferometry [10] (μm).…”

“…In other words, one can measure the current density by knowing the thickness of the oxide film. The thickness of the oxide film can be measured by Fabry-Perot interferometry [10]. Therefore, Equation (1) can be applied to measure the current density of the aluminum oxide of aluminum samples during the anodization process of the aluminum in sulfuric acid solutions.…”

“…Meanwhile, a reflection spectrum obtained from Fabry-Perot interferometry was recorded by the high-density spectrometer after a specific time interval (every 10 minutes). Subsequently, the current density (J) of the aluminum oxide film was obtained during the formation of the oxide film [10]. Eventually, the abrupt rate change of the current density (dJ) of the aluminum samples in 0, 2, 4, 6, 8, 10% H2SO4 solutions was determined.…”

“…No attempt was made by the other investigators to quantify the optical interferometry patterns of metallic samples under the anodic dissolution processes by coherent light, laser light thus far. On the contrary, in a current study, the author has managed for the first time to monitor the electrical resistance of the aluminum oxide films during the anodization process by non-coherent (white) light methods, like Fabry-Perot interferometry, i.e., spectral optical-sensor [10].…”