Laser optical interferometry as a zero resistance ammeter: fundamental and applications

It is well known that electronics instrumentation, i.e. Ammeter, Potential-meter, have been used for years to measure electrochemical properties of metallic electrodes in aqueous solutions. One of the disadvantages of using electronic instruments for the measurement of electrochemical properties is the invasive nature of those instruments to the electrochemical systems of the metallic electrodes in aqueous solutions. In recent works published elsewhere [1–16], it has been shown that laser optical interferometry can be used as an optical transducer to characterize the electromagnetic field, i.e. phase and amplitude of the reflected light waves of a surface of a metallic electrode moving further away from the light source, which develops as a result of the electron conduction in metallic electrodes in aqueous solutions due to the anodic reaction, corrosion processes, between the electrodes and the aqueous solutions. The characterization of such electromagnetic field (phase and amplitude of the reflected light waves of a surface) and a mathematical correlation of the electromagnetic field to any electrochemical properties, i.e. corrosion current density, double layer capacitance, alternating current impedance, and so on, would lead to the measurement of the electrochemical properties by optical interferometry, by the non-invasive method. In the present work, the corrosion current density of a pure Copper (99.8% Cu), an Aluminum–Brass alloy (76% Cu, 22% Ni, and 2% Al), and a Stainless steel (UNS No.304 Stainless steel, 19% Cr, 9% Ni, 0.45% Mn, and rest Fe) were obtained in natural seawater, respectively. Also, the corrosion current density of the same Stainless steel (UNS No.304 stainless steel, 19% Cr, 9% Ni, 0.45% Mn, and rest Fe) was obtained in 1 M NaCl solution. The obtained corrosion data from the optical interferometry technique, as a zero resistance ammeter were compared with corrosion data obtained on the same alloys in the specified solutions from an electronic zero resistance ammeter as well as from the linear polarization method. The comparison among the three techniques indicates that there is contrast in the results among the investigated alloys. In general, the results of the optical interferometry were found in agreement with the electronic zero resistance ammeter as compared with the linear polarization method. As a result, the optical interferometry can be considered as a useful zero resistance Ammeter for measuring the corrosion current density of metallic electrodes in aqueous solutions at the open circuit potential of the electrodes in the aqueous solutions.

[1]  Michael Rohwerder,et al.  Electrochemical Techniques for Corrosion , 2003 .

[2]  K. Habib,et al.  Detection of localized corrosion of stainless steels by optical interferrometry , 1999 .

[3]  K. Habib.  Crevice corrosion of copper alloys by optical interferometry , 1999 .

[4]  K. Habib.  In-situ monitoring of pitting corrosion of copper alloys by holographic interferometry , 1998 .

[5]  Khaled J. Habib,et al.  Monitoring Pitting Corrosion by Holographic Interferometry , 1997 .

[6]  K. Habib.  Measurement of the a.c. impedance of aluminium samples by holographic interferometry , 1997 .

[7]  K. Habib,et al.  Interferometric Sensor for Electrochemical Studies of Metallic Alloys in Aqueuos Solution , 1997 .

[8]  K. Habib.  Measurement of the double layer capacitance of aluminium samples by holographic interferometry , 1996 .

[9]  Khaled J. Habib,et al.  Measurement of the double layer-capacitance of aluminium samples by holographic interferometry , 1996, International Commission for Optics.

[10]  Khaled J. Habib,et al.  Optical corrosion meter , 1995, Other Conferences.

[11]  K. Habib.  Non-destructive evaluation of metallic electrodes under corrosion fatigue conditions by holographic interferometry , 1995 .

[12]  Khaled J. Habib,et al.  Nondestructive evaluation of an epoxy-based coating by optical interferometry techniques , 1994, Optics & Photonics.

[13]  K. Habib.  Initiation of stress corrosion cracking of Ti90-Al6-V4 wire in aqueous solution: Non-destructive monitoring by holographic interferometry , 1994 .

[14]  R. Lakes,et al.  Technique for Measuring Stress Corrosion Cracking of Metallic Electrodes in Aqueous Solutions , 1993 .

[15]  K. Habib.  Model of holographic interferometry of anodic dissolution of metals in aqueous solution , 1993 .

[16]  Khaled J. Habib,et al.  Holographic interferometry in predicting cathodic deposition of metals in aqueous solution , 1990, Marketplace for Industrial Lasers.

[17]  K. Habib.  Holographic interferometry of polarized and loaded metallic electrodes in aqueous solution. , 1990, Applied Optics.

[18]  Khaled J. Habib,et al.  Holographic Interferometry Of A Polarized And Loaded Metallic Electrodes In Aqueous Solution , 1990, Other Conferences.

[19]  K. Habib.  The initial behaviour of corrosion fatigue/hydrogen embrittlement of metallic electrodes in aqueous solution , 1990 .

[20]  P. Boden.  Corrosion and corrosion control , 1986 .

[21]  Robert Baboian,et al.  Electrochemical techniques for corrosion : Symposium on Electrochemical Techniques for Corrosion at the NACE Corrosion/76 meeting held in Houston, Texas, March 22-26, 1976 , 1977 .