Electrochemical Noise Analysis of the X70 Pipeline Steel under Stress Conditions Using Symmetrical and Asymmetrical Electrode Systems
Andres Carmona-Hernández,
Ricardo Orozco-Cruz,
Franco Antonio Carpio-Santamaria,
Clarisa Campechano-Lira,
Francisco López-Huerta,
Edgar Mejía-Sánchez,
Antonio Contreras,
Ricardo Galván-Martínez
Affiliations
Andres Carmona-Hernández
Instituto de Ingeniería, Universidad Veracruzana, S. S. Juan Pablo II, Zona Universitaria, Boca del Río 94294, Veracruz, Mexico
Ricardo Orozco-Cruz
Instituto de Ingeniería, Universidad Veracruzana, S. S. Juan Pablo II, Zona Universitaria, Boca del Río 94294, Veracruz, Mexico
Franco Antonio Carpio-Santamaria
Instituto de Ingeniería, Universidad Veracruzana, S. S. Juan Pablo II, Zona Universitaria, Boca del Río 94294, Veracruz, Mexico
Clarisa Campechano-Lira
Instituto de Ingeniería, Universidad Veracruzana, S. S. Juan Pablo II, Zona Universitaria, Boca del Río 94294, Veracruz, Mexico
Francisco López-Huerta
Facultad de Ingeniería Eléctrica y Electrónica, Universidad Veracruzana, Adolfo Ruiz Cortines No. 455, Fracc. Costa Verde, Boca del Río 94294, Veracruz, Mexico
Edgar Mejía-Sánchez
Facultad de Ingeniería, Universidad Veracruzana, KM 1.0 Carretera Sumidero Dos Ríos, Veracruz 94452, Veracruz, Mexico
Antonio Contreras
Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas Norte 152, Col. San Bartolo Atepehuacan, Alcaldía Gustavo A. Madero, Mexico City 07730, Mexico
Ricardo Galván-Martínez
Instituto de Ingeniería, Universidad Veracruzana, S. S. Juan Pablo II, Zona Universitaria, Boca del Río 94294, Veracruz, Mexico
In this work, electrochemical monitoring of stress corrosion cracking (SCC) behavior of a X70 steel in acidic synthetic soil solution during the slow strain rate test (SSRT) was performed by electrochemical noise (EN) using the conventional arrangement of symmetrical electrodes and electrochemical emission spectroscopy (EES) using the asymmetrical arrangement replacing the second working electrode for a platinum micro-cathode. The statistical method, fast Fourier transform, and discrete wavelet transform were used for analyzing the potential and current signals recorded by both arrangements. The results showed that EN arrangement was more effective to detect the crack initiation at a point close to yield strength despite stress-induced asymmetry in one of the electrodes. For the EES arrangement, the micro-cathode had a strong influence on the electrochemical noise of the current and potential under stress conditions. From the transient features, statistical parameters, and wavelet analysis, a discontinuous transgranular SCC mechanism was found. The resistance values obtained by EN measurements had better correlation with the electrochemical impedance spectroscopy results (EIS) than EES measurements.
