Improvement of the linear polarization resistance method for testing steel corrosion inhibitors

RESUMENSe estudió la factibilidad del uso de partículas de neumático reciclado en concreto y morteros. Para evaluar las propiedades mecánicas del concreto endurecido se realizaron pruebas de densidad, resistencia a la compresión y determinación del módulo de elasticidad. Además se determinó la trabajabilidad del concreto en estado fresco mediante la prueba de revenimiento Las muestras se fabricaron con la sustitución de un 5%, 7.5% y 10 % del volumen de la arena por partículas de neumático reciclado. Se determinó mediante la técnica de potencial de corrosión el estado que guardaba en acero revisando de esta manera la probabilidad de corrosión. Para el estudio de la velocidad de corrosión se utilizó la técnica electroquímica de resistencia a la polarización lineal (RPL) en morteros fabricados bajo las mismas condiciones y proporciones que en los concretos. Los resultados mostraron que una mezcla con 7.5% de partículas de neumático reciclado puede ser utilizada en estructuras de resistencia moderada, ligera y ubicadas en ambientes con cloruros.Palabras clave: Concreto; mortero; neumático reciclado; velocidad de corrosión; Propiedades mecánicas.ABSTRACTThe feasibility of using scrap tire particles in the elaboration of concrete and mortar was investigated. To assess the mechanical properties of hardened concrete, tests evaluating of its density, modulus elasticity and compression strength were undertaken. To determine the workability of freshly made concrete, a slump test was also performed. Tests in which 5, 7.5 and 10% of sand were substituted by recycled tire particles were made. The likelihood of corrosion on the steel is determined, using the technique of corrosion potential. To test the velocity of corrosion was used the linear polarization resistance method (LPR method) was utilized under the same conditions as well as fabrication of concrete. It was observed that using 7.5% of recycled tire particles offers satisfactory results in structures of moderate strength and lighter weight located in environments with chlorides.Keywords: Concrete; mortar; recycled tire; corrosion rate; mechanical properties.

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Anti-tarnish silver alloys in system Ag-Cu-Zn-Si with the addition of aluminum

Metallurgical and Materials Engineering ◽

10.30544/386 ◽

2018 ◽

Vol 24 (3) ◽

pp. 181-188

Author(s):

Marija Korać ◽

Stevan Dimitrijević ◽

Kemal Delijić ◽

Željko Kamberović

Keyword(s):

Linear Polarization ◽

Polarization Resistance ◽

Open Circuit Potential ◽

Sodium Sulfide ◽

Open Circuit ◽

Silver Alloys ◽

Linear Polarization Resistance ◽

Sodium Sulfide Solution ◽

Sulfide Solution ◽

Polarization Resistance Method

This paper presents investigations of aluminum addition influence on the corrosion characteristics of the sterling silver Ag-Cu-Zn-Si alloys. The procedure for obtaining Ag-Cu-Zn-Al-Si alloys in small ranges of predefined composition was also presented. Open circuit potential measurements, linear polarization resistance method and potentiodynamic polarization tests were employed to determine corrosion characteristics of the alloys. The materials were tested in a 0.01M sodium sulfide solution. It was shown that the addition of aluminum improves sulfidization resistance and corrosion characteristics. Best results are achieved for the alloy with the following composition 92.5% Ag, 1.9% Cu, 3.7% Zn, 1.6% Al and 0.3% Si.

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The Protection of Reinforcing Steel in Concrete by Migrating Corrosion Inhibitor

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.629-630.136 ◽

2014 ◽

Vol 629-630 ◽

pp. 136-143

Author(s):

J.S. Cai ◽

C.C. Chen ◽

J.Z. Liu ◽

L. Shi

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Carbon Steel ◽

Impedance Spectroscopy ◽

Corrosion Inhibitor ◽

Linear Polarization ◽

Polarization Resistance ◽

Corrosion Inhibitors ◽

Electrochemical Impedance ◽

Reinforcing Steel ◽

Linear Polarization Resistance

In this paper, the performance of two kinds of migrating corrosion inhibitors on the corrosion behavior of steel in concrete under wet-dry cycle was investigated. The wet-dry cycle duration on the open circuit, current density and impedance of carbon steel imbedded in concrete were analyzed by linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS). The results show that two kinds of migrating corrosion inhibitors can restrain corrosion of reinforcing steel, the corrosion efficiency of ZX was less more than MCI. Migrating corrosion inhibitor not only can improve carbon steel impedance, also can improve concrete resistant. Key words: migrating corrosion inhibitor;Cl-;reinforcing steel;linear polarization resistance;electrochemical impedance spectroscopy

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Error Estimation of Linear Polarization Resistance Measurement Caused by IR Drop for Reinforcement Corrosion in Concrete

Materials Science Forum ◽

10.4028/www.scientific.net/msf.866.14 ◽

2016 ◽

Vol 866 ◽

pp. 14-19

Author(s):

Jin Xia Xu ◽

Ya Long Cao ◽

Lin Hua Jiang ◽

Ying Bin Song ◽

Wei Feng

Keyword(s):

Linear Polarization ◽

Polarization Resistance ◽

Chloride Content ◽

Chloride Ions ◽

Resistance Measurement ◽

Reinforcing Steel ◽

Error Level ◽

Corrosion Condition ◽

Linear Polarization Resistance ◽

Ir Drop

In order to evaluate more accurately the corrosion condition of reinforcing steel in chloride contaminated concrete, it is significant to investigate the error level in the linear polarization resistance measurement caused by IR drop. Concretes with eight levels of chloride ions (ranging from 0% to 2.0% by mass of cement) by adding different amounts of sodium chloride in the mixing water were prepared. Linear polarization measurements with and without IR compensation, were applied to determine the error level. Besides, half-cell potential method was employed to detect the corrosion condition of reinforcing steel. The results indicate that the error level is so low (less than 5.0%) that the IR drop can be negligible when the chloride content is relatively lower (0.6% or less by mass of cement). However, the error level is increased with the increase of chloride content. The IR drop is suggested to be compensated when the chloride content is relatively higher (more than 0.6% by mass of cement). At this time, the onset of active corrosion of reinforcing steel is also found.

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A Lifetime of Metallic Nanoparticles in Heat Exchange Liquids

Materials Science Forum ◽

10.4028/www.scientific.net/msf.811.23 ◽

2014 ◽

Vol 811 ◽

pp. 23-27 ◽

Cited By ~ 1

Author(s):

Jan Stoulil ◽

Tomáš Pfeifer ◽

Alena Michalcová ◽

Ivo Marek

Keyword(s):

Aqueous Solution ◽

Heat Exchange ◽

Mass Loss ◽

Linear Polarization ◽

Polarization Resistance ◽

Metallic Nanoparticles ◽

Iron Nanoparticles ◽

Corrosion Prevention ◽

Linear Polarization Resistance ◽

Formate Solution

This work is focused on lifetime prediction of metallic nanoparticles in heat exchange nanofluids. Copper, nickel and iron nanoparticles were studied in 40 wt.% aqueous solution of potassium formate and propylene glycol. Materials were observed by means of mass loss exposure tests, linear polarization resistance and potentiodynamic measurements. Potassium formate solution is not suitable bearing liquid for metallic nanoparticles. Propylyne glycol seems promising, however additional corrosion prevention needs to be applied.

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