Media and Publications

Materials Performance, 2004 April Issue, page 15

Corr Instruments (San Antonio, Texas) introduces its nanoCorr® coupled multielectrode sensor analyzer for online and real-time corrosion monitoring. Used in conjunction with the company’s software, CorrVisualTM, the analyzer is used to monitor localized corrosion as well as most types of general corrosion in liquids, soils, bio-deposits and humid gases. In many applications, the analyzer is sensitive for corrosion rates near 10 nm/year (or 4x10-4 mil/year)….

San Antonio Business Journal, May 12, 2004

Local scientists develop system for monitoring corrosion- Engineers at Southwest Research Institute (SwRI) have developed a new system to monitor the rate of corrosion in bridges, aircraft, power plants, pipelines and refineries. The institute's Multielectrode Array Sensor System (MASS) specifically measures localized corrosion -- one of the most common reasons for failures in engineering components…

http://austin.bizjournals.com/sanantonio/stories/2004/05/10/daily23.html

Materials Performance, 2004 August Issue, page 12

Monitoring Localized Corrosion -Engineers at Southwest Research Institute (SwRI) (San Antonio, Texas) have developed a sensor technology that reportedly can perform real-time monitoring of localized corrosion in structures such as bridges, chemical plants, pipelines, refineries, and aircraft. “Th e Multielectrode Array Sensor System [MASS] can be tailored to meet the process needs of a variety of industries,” says Narasi Sridhar, Program Director in SwRI’s Mechanical and Materials Engineering Division. According to SwRI, MASS uses multiple miniature electrodes composed of materials identical to the component being tested as the sensing electrode. The electrodes are coupled together by connecting each to a common joint through independent small resistors. Each electrode simulates part of a corroding metal. The voltage drop across the resistors produces anodic and cathodic currents, which signal localized corrosion…..

Southwest Research Institute (SwRI) News, San Antonio -- May 11, 2004

http://www.swri.org/9what/releases/2004/Sensor.htm

or http://www.swri.org/3pubs/IRD2001/20-9209.htm

SwRI® researchers develop system for real-time monitoring of corrosion--Engineers at Southwest Research Institute® have developed the Multielectrode Array Sensor System (MASS) for real-time monitoring of localized corrosion in structures such as bridges and aircraft and in chemical plants, power plants and refineries. Localized corrosion is one of the most common failure modes for engineering components. Corrosion often results in high rates of metal penetration and leads to premature component failure even though much of the metal surface may not be affected. MASS uses multiple miniature electrodes composed of materials identical to the component being tested as the sensing electrode. The electrodes are coupled together by connecting each to a common joint through independent small resistors, with each electrode simulating part of a corroding metal…

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Selected Advertisements

Materials Performance, 2004 February Issue, page 55:

Coupled Multielectrode Sensor Analyzer for Real-Time Monitoring of Localized Corrosions- Building upon patented coupled multielectrode sensor technology, our nanoCorr® Analyzers and CorrVisualTM software make the real-time monitoring of localized and most types of general corrosions easy and accurate in liquids, soils, bio-deposits and gases….

Materials Performance, 2004 September Issue, page 37:

Multielectrode Array Sensor Analyzer for Real-Time Monitoring of Localized Corrosions-- Building upon patented multielectrode array sensor technology, and protected by several other U.S. and international pending patents, our nanoCorr® Analyzers and CorrVisualTM software make quantitative and real-time monitoring of localized and general corrosions easy and reliable in liquids, soil, concrete, bio-deposits and gases.

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Materials Performance, Corrosion Engineering Directory, Every Issue of the Journal since May 2004

Materials Performance Buyers Guide, 2004 Issue, Page 88

Materials Performance, February Issue, page 55 and March Issue, page 109

Materials Performance, September Issue, page 37, 2004

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Publications and Selected Abstracts

2005

1 “Online Monitoring of Undercoating Corrosion Using Coupled Multielectrode Sensors", by X. Sun, To be published, Materials Performance, 44(3), March (2005).

2 "Online and Real-Time Monitoring of Carbon Steel Corrosion in Concrete, Using Coupled Multielectrode Sensors,” by X. Sun, CORROSION/2005, paper no. 05267 (Houston, TX: NACE International, 2005).

3 “Real-Time Corrosion Monitoring in Soil with Coupled Multielectrode Sensors,” by X. Sun, CORROSION/2005, paper no. 05381 (Houston, TX: NACE International, 2005).

4 "Laboratory Evaluation of a Multi-Array Sensor for Detection of Under Deposit Corrosion and/or Microbiologically Influenced Corrosion", M. H. Dorsey, D.R. Demarco, G. A. Fisher, and B. J. Saldanha, CORROSION/2005, paper no. 05371 (Houston, TX: NACE International, 2005).

5 "An Improved Method for Real-Time and Online Corrosion Monitoring, Using Coupled Multielectrode Array Sensors," L. Yang, D. S. Dunn, and G. A. Cragnolino, CORROSION/2005, paper no. 05379 (Houston, TX: NACE International, 2005).

6 "Real-Time Monitoring of Carbon Steel Corrosion in Crude Oil and Salt Water Mixtures Using Coupled Multielectrode Sensors," L. Yang, Y-M. Pan, D.S. Dunn, and N. Sridhar, CORROSION/2005, paper no. 05293 (Houston, TX: NACE International, 2005).

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2004

1. “Monitoring Localized Corrosion”, by M.V. Veazey, Materials Performance, August (2004): p.12.

Engineers at Southwest Research Institute (SwRI) (San Antonio, Texas) have developed a sensor technology that reportedly can perform real-time monitoring of localized corrosion in structures such as bridges, chemical plants, pipelines, refineries, and aircraft. “Th e Multielectrode Array Sensor System [MASS] can be tailored to meet the process needs of a variety of industries,” says Narasi Sridhar, Program Director in SwRI’s Mechanical and Materials Engineering Division. According to SwRI, MASS uses multiple miniature electrodes composed of materials identical to the component being tested as the sensing electrode. The electrodes are coupled together by connecting each to a common joint through independent small resistors. Each electrode simulates part of a corroding metal. The voltage drop across the resistors produces anodic and cathodic currents, which signal localized corrosion…..

2 “What’s New in the Water Industry?” by Arthur J. Freedman, Materials Performance, May (2004): p.8.

….In another field study of underdeposit corrosion, arrays of microelectrodes were used to simulate anodes and cathodes on metal surfaces. The results accurately simulated microbiologically influenced corrosion observed on carbon steel exposed in a contaminated surface water. These techniques and others may someday become practical tools for monitoring underdeposit corrosion in cooling water systems…..

3 "Online Monitoring of Undercoating Corrosions Utilizing Coupled Multielectrode Sensors", by X. Sun, CORROSION/2004, paper no. 04033, (Houston, TX: NACE International, 2004).

Abstract: Online monitoring of carbon steel corrosion under different commercial coatings was conducted, utilizing coupled multielectrode sensors. The experimental results showed that the coupled multielectrode corrosion sensor is an effective tool for detecting initial defects and real-time degradation of the coatings. Because of their high sensitivity, the coupled multielectrode sensors may also be used as a quick and convenient tool for optimizing the selection of proper coatings for different applications.

4 "Online Monitoring of Corrosion under Cathodic Protection Conditions Utilizing Coupled Multielectrode Sensors", by X. Sun, CORROSION/2004, paper no. 04094, (Houston, TX: NACE International, 2004).

Abstract: Real-time corrosion monitoring for carbon steel materials in simulated seawater under cathodic protection conditions was conducted, utilizing coupled multielectrode sensors. It was demonstrated that the coupled multielectrode sensor is an effective real-time tool for monitoring the effectiveness of cathodic protection and for measurement of the threshold value of the protection potential for specific equipment.

5 “Cooling Water Monitoring Using Coupled Multielectrode Array Sensors and Other On-line Tools”, by M. H. Dorsey, L. Yang and N. Sridhar, CORROSION/2004, paper no. 04077, (Houston, TX: NACE International, 2004).

Abstract: Real-time coupled multielectrode array sensors (MAS) and other monitoring tools were used to evaluate a complex corrosion phenomenon on carbon steel in a large industrial cooling water system. The design and implementation of the monitoring system, and monitoring results are discussed in this paper. Characterization of the degree and depth of attack from the MAS probe showed excellent correlation with characterization of underdeposit attack on corrosion coupons that were exposed simultaneously with the MAS probe.

6 "Real-Time Corrosion Monitoring in a Process Stream of a Chemical Plant Using Coupled Multielectrode Array Sensors”, by L. Yang and N. Sridhar, S. L. Grise, B. J. Saldanha, M.H. Dorsey, H. J. Shore and A. Smith, CORROSION/2004, paper no. 04440, (Houston, TX: NACE International, 2004).

Abstract: Coupled multielectrode array sensors made of Type 316L stainless steel, AL6XN and Alloy C-276 alloys were used as real time-sensors to monitor localized corrosion in a side loop of a process stream in a chemical plant. The pitting corrosion rates measured from the probes made of stainless steel and nickel-chromium alloys are consistent with the pitting resistance equivalent numbers of the alloys and with the plant experience. The pitting rate obtained from the long-term measurement is in good agreement with the actual corrosion rate obtained from the posttest surface examination of the probes.

7 "Laboratory Comparison of Coupled Multielectrode Array Sensors with Electrochemical Noise Sensors for Real-Time Corrosion Monitoring”, by L. Yang, N. Sridhar, D. S. Dunn and C. S. Brossia, CORROSION/2004, paper no. 04033, (Houston, TX: NACE International, 2004).

Abstract: The performance of the electrochemical noise sensors made of carbon steel and stainless steels were tested and compared with the coupled multielectrode array sensors made of the same materials as real-time corrosion sensors. No correlation was observed between the pit index signals for localized corrosion from the electrochemical noise sensors and the corrosivity of the solution. The noise resistance signals for general corrosion that were averaged over long time intervals appeared to correlate with the corrosivity of the solutions However, the fluctuation of noise resistance signals was significant and often overwhelmed the measured signals. Averaging over long time intervals were required to obtain meaningful noise resistance signals for the electrochemical noise (EN) sensors. Thus the EN sensors may not be reliable for real-time measurement of localized corrosion. It may be used for real-time measurement of general corrosion. The responses of the coupled multielectrode array sensors to the localized corrosivity of the solutions were excellent.

8 “Sensor Array and Method for Electrochemical Corrosion Monitoring”, L. Yang and N. Sridhar, U.S. Patent No. 6,683,463 (2004).

9 “Studies on The Corrosion Behavior of Stainless Steels in Chloride Solutions in the Presence of Sulfate Reducing Bacteria”, by L. Yang and G. A. Cragnolino, CORROSION/2004, paper no. 04598, (Houston, TX: NACE International, 2004).

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2003

1 Monitoring of Localized Corrosion”, by L. Yang and N. Sridhar, in ASM Handbook, Volume 13A-Corroson: Fundamentals, Testing, and Protection, Stephen. D. Crammer and Bernard S. Covino, Jr. Eds, ASM International, Materials Park, Ohio, 2003, pp 519-524.

2 “Coupled Multielectrode Online Corrosion Sensor”, L. Yang and N. Sridhar, Materials Performance, 42(9) September (2003): p.48-52.

This article describes the development, application, and validation of a new sensor to monitor nonuniform and localized corrosion in many different applications. The main advantage of this sensor is its ability to monitor localized corrosion in real-time

3 “Studies of Microbiologically Influenced Corrosion Using a Coupled Multielectrode Array Sensor”, by C. Sean Brossia and Lietai Yang, ,CORROSION/2003, paper no. 03575, (Houston, TX: NACE International, 2003).

Abstract: A newly developed multielectrode array sensor (MASS) was used to conduct a series of abiotic and biotic tests to determine if the probe can detect corrosion induced by microbial activity. The probe was able to determine the maximum corrosion rate in the presence of sulfate reducing bacteria (SRB) and showed that this rate was at least a factor of 10 greater than in the absence of SRBs. In addition, the corrosion rates obtained using the probe were much higher than those determined using linear polarization resistance further demonstrating its inherent better sensitivity to localized corrosion.

4 "The Study of Atmospheric Corrosion of Carbon Steel and Aluminum under Salt Deposit Using Coupled Multielectrode Array Sensors", by L. Yang, Roberto T. Pabalan and Darrell S. Dunn, the 204th Meeting of the Electrochemical Society, Abstract #465, Extended Abstract Volume 2003-II (Pennington, NJ: Electrochemical Society, 2003).

5. “Development of Sensors for Waste Package Testing and Monitoring in the Long Term Repository Environments”, V. Jain, S. Brossia, D. Dunn, and L. Yang, Ceramic Transactions, Vol. 143, pp. 283-290, 2003, American Ceramic Society, Westerville, OH

6 “Corrosion Behavior of Carbon Steel and Stainless Steel Materials under Salt Deposits in Simulated Dry Repository Environments”, by L. Yang, R. T. Pabalan, L. Browning and D.S. Dunn,, in Scientific Basis for Nuclear Waste Management XXVI, R. J. Finch and D. B. Bullen eds, Warrendale, PA: Materials Research Society, M.R.S. Symposium Proceedings, Vol. 757, pp.791-797, 2003.

Abstract: In-situ coupled multielectrode array sensors were used to measure the non-uniform corrosion of carbon steel and stainless steel materials under KCl salt deposit in simulated dry repository environments. It was found that the initiation of non-uniform corrosion occurs at a relative humidity that is 14% lower than the deliquescence relative humidity of the chloride salt. It was found also that once significant corrosion had occurred, the non-uniform corrosion process for the carbon steel material under the salt deposit continues at relative humidities as low as 27%.

7 “Measurement of Corrosion in Saturated Solutions under Salt Deposits Using Coupled Multielectrode Array Sensors”, by L. Yang, R. T. Pabalan, L. Browning, and G. A. Cragnolino, CORROSION/2003, paper no. 03426, (Houston, TX: NACE International, 2003).

Abstract: The corrosion rates of type 1010 carbon steel, and types 304 and 316 stainless steels in saturated solutions under salt deposits were measured using coupled multielectrode sensors. The measurements were carried out in the presence of the following salts: KCl, NaCl, NaNO3, MgCl2, NiCl2, FeCl3, FeCl2, CuCl2, and an NaCl+NaNO3 mixture.

The results indicate that the corrosiveness of the salts increased in the following order:

KCl ~ NaCl ~ NaNO3 ~ NaCl+NaNO3 ~ MgCl2 < NiCl2 < FeCl3 < FeCl2 < CuCl2

for carbon steel, and

KCl ~ NaCl ~ MgCl2 ~ NiCl2 ~ NaCl+NaNO3 < FeCl3 ~ FeCl2 ~ CuCl2

for type 304 stainless steel. Some inhibition of corrosion of type 316 stainless steel by NaNO3 was observed in a mixture of NaCl+NaNO3, but not in pure NaNO3 solution.

8 “An Electrochemical Approach to Predicting and Monitoring Localized Corrosion in Chemical Process Streams”, by A. Anderko, N. Sridhar, C. S. Brossia, D. S. Dunn, L.T. Yang, B.J. Saldanha, S.L. Grise, and M.H. Dorsey, CORROSION/2003, paper no. 03375, (Houston, TX: NACE International, 2003).

Abstract: A general model for predicting the occurrence of localized corrosion in chemical process streams is described. The model predicts the repassivation and corrosion potentials based on input chemistry of a system. The model predictions are compared to experimental data. Initial data from a validation study using a multielectrode array sensor at a process plant is described.

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2002

1 “Evaluation of Corrosion Inhibitors in Cooling Water Systems Using a Coupled Multielectrode Array Sensor”, by L. Yang, and D. S. Dunn, CORROSION/2002, paper no. 02004, (Houston, TX: NACE International, 2002).

Abstract: A multielectrode localized corrosion sensor has been developed for evaluating the performance of corrosion inhibitors for carbon steel in cooling water. Experimental results indicate that the coupled multielectrode sensor provided instantaneous measurement of corrosion currents and a rapid real-time response to the addition of inhibitors. Evaluation of several inhibitors showed that the sensor was able to distinguish between inhibitor type and concentration. It was also demonstrated that the sensor has a detection limit of 5x10-11A with respect to current measurement. The capabilities of the sensor may be suitable for online monitoring of corrosion in a variety of applications where real-time monitoring is required.

2 “Comparison of Localized Corrosion of Fe-Ni-Cr-Mo Alloys in Concentrated Brine Solutions Using a Coupled Multielectrode Array Sensor”, by L. Yang, N. Sridhar, and G. Cragnolino, CORROSION/2002, paper no. 545, Houston, TX: NACE International, 2002).

Abstract: A multielectrode localized corrosion sensor was developed and used for comparing localized corrosion of Fe-Ni-Cr-Mo alloys in chloride solutions. Experimental results indicated that the coupled multielectrode sensor provides a rapid real-time response to changes in temperature and salt concentration. It was demonstrated that the sensor has a lower detection limit of 5×10-11 A with respect to corrosion current and 2x10-8 A/cm2 with respect to the corrosion current density for the miniature electrodes used in the sensors.

3 “An In-situ Galvanically Coupled Multielectrode Array Sensor for Localized Corrosion”, by L. Yang, N. Sridhar, O. Pensado, and D. S. Dunn, Corrosion, 58 (2002): p.1004-1014.

Abstract: A localized corrosion sensor consisting of multiple, corrodible, miniature electrodes was tested in different chemical environments. The miniature electrodes were coupled together by connecting each of them to a common joint through independent resistors, with each electrode simulating an area of a corroding metal. In a localized corrosion environment, anodic currents flow into the more corroding electrode, and cathodic currents flow out of the less or noncorroding electrodes. These currents are measured from the voltages across the resistors. The variation among the galvanic currents measured from the miniature electrodes responded well to changes of the environment with respect to localized corrosion. It was demonstrated that statistical parameters derived from the currents flowing through the miniature electrodes, such as the standard deviation or the 90th percentile anodic value, can be used as effective indictors for localized corrosion. Measurement has shown the following order of corrosiveness of the environment for UNS S30400 stainless steel:

deionized water < saturated KCl < 1 M NaNO3 + 0.25 M FeCl3 < 0.0025 M FeCl3 < 0.25 M FeCl3.

It was also shown that the penetration rate of localized corrosion may be estimated from either the measured maximum or the standard deviation of the anodic current densities, and the cumulative penetration may be estimated from either the measured maximum or the standard deviation of the cumulative anodic charges through the electrodes.

4 “Corrosion Sensing and Monitoring”, by C.S. Brossia, L. Yang, D.S. Dunn, N. Sridhar, in Proceedings of Tri-Service Corrosion Conference, Jan. 14-18, 2002, San Antonio, TX.

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2001

“Development of a Multielectrode Array Sensor for Monitoring Localized Corrosion”, by L. Yang, N. Sridhar, and O. Pensado, Presented at the 199th Meeting of the Electrochemical Society, Abstract #182, Extended Abstract Volume I, (Pennington, NJ: Electrochemical Society, 2001).

1 Use of Multi-Array Sensor for Detecting Microbially Influenced Corrosion

—by P. Angell and K. McQuade, Atomic Energy of Canada, Canada

2 Field Application of Coupled Multielectrode Array Sensors for Corrosion Monitoring in the Cooling Water System of a Chemical Plant

—by Michael Dorsey, DuPont Engineering Technology, USA

3 Latest Developments in Utilizing the Wire Beam Electrode Method for Corrosion Prevention Research and for Corrosion Monitoring

—by Yong-Jun Tan, School of Materials, Nanyang Technological University, Singapore

4 New Sensors of Wire Beam Electrodes to Detect Pitting Sensitivity of Stainless Steel in NaCl Solutions

—by Weng Yongji, University of Petroleum, China

5 Coupled Multielectrode Array Sensor—A new Generation of Online Corrosion Sensor

—by Lietai Yang and Narasi Sridhar, Southwest Research Institute, USA.

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