Effect of natural aging on the microstructural regions, mechanical properties, corrosion resistance and fracture in welded joints on API5L X52 steel pipeline


  • Benjamín Vargas-Arista Instituto Tecnológico de Tlalnepantla, División de Estudios de Postgrado e Investigación
  • Apolinar Albiter Instituto Mexicano del Petróleo
  • Felipe García-Vázquez Corporación Mexicana de Investigación en Materiales, Postgrado en Tecnología de la Soldadura Industrial, Ciencia y Tecnología
  • Óscar Mendoza-Camargo Instituto Tecnológico de Tlalnepantla, División de Estudios de Postgrado e Investigación
  • José Manuel Hallen Departamento de Ingeniería Metalúrgica, IPN-ESIQIE, Laboratorios Pesados de Metalurgia, UPALM Zacatenco




API5L X52 steel, Coarsening, Degradation, HAZ, Natural aging


A characterization study was done to analyze how microstructural regions affect the mechanical properties, corrosion and fractography of the Heat Affected Zone (HAZ), weld bead and base metal for pipe naturally aged for 21 years at 30 °C. Results showed that microstructures exhibited damage and consequently decrease in properties, resulting in over-aged due to service. SEM analysis showed that base metal presented coarse ferrite grain. Tensile test indicated that microstructures showed discontinuous yield. Higher tensile strength was obtained for weld bead, which exhibited a lower impact energy in comparison to that of HAZ and base metal associated with brittle fracture by trans-granular cleavage. The degradation of properties was associated with the coarsening of nano-carbides observed through TEM images analysis, which was confirmed by SEM fractography of tensile and impact fracture surfaces. The weld bead reached the largest void density and highest susceptibility to corrosion in H2S media when compared to those of the HAZ and base metal.


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API 5L (2008). Specification for Line Pipe, 44th Ed., American Petroleum Institute, Washington D.C., USA, pp. 8–17.

ASTM Standard G-102 (2004). Standard Practice for Calculation of Corrosion Rates and Related Information from Electrochemical Measurements. ASTM International, West Conshohocken, PA, USA, pp. 1–5.

ASTM Standard E-112 (2004). Standard Test Methods for Determining Average Grain Size. ASTM, West Conshohocken, PA, USA, pp. 10–12.

ASTM Standard E-384 (2005). Standard Test Method for Microindentacion Hardness of Materials. ASTM, West Conshohocken, PA, USA, pp. 1–8.

ASTM Standard E-23 (2006). Standard Test Methods for Notched Bar Impact Testing of Metallic Materials. ASTM, West Conshohocken, PA, USA, pp. 2–8.

ASTM Standard E-8M (2008). Standard Test Methods for Tension Testing of Metallic Materials. ASTM, West Conshohocken, PA, USA, pp. 7–18.

AWS A5.17 (2004). Specification for Carbon Steel Electrodes and Fluxes for Submerged Arc Welding. American Welding Society, Miami FL, USA, pp. 2–4.

Hamada, I., Yamauchi, K. (2002). Sensitization behavior of type 308 stainless steel weld metals after postweld heat treatment and low temperature aging and its relation to microstructure. Metall. Mater. Trans. A 33 (6), 1743–1754. http://dx.doi.org/10.1007/s11661-002-0183-5

Homma K., Miki C., Yang, H. (1998). Fracture toughness of cold worked and simulated heat affected structural steel. Eng. Fract. Mech. 59 (1), 17–28. http://dx.doi.org/10.1016/S0013-7944(97)00100-8

Jayan, V., Khan, Y.M., Husain, M. (2004). Coarsening of nano sized carbide particles in 2.25Cr–1Mo power plant steel after extended service. Mater. Lett. 58 (21), 2569–2573. http://dx.doi.org/10.1016/j.matlet.2004.02.051

Kotrechko, O.S., Krasowsky, Y.A., Meshkov, Y.Y., Torop, M.V. (2004). Effect of long-term service on the tensile properties and capability of pipeline steel 17GS to resist cleavage fracture. Int. J. Pres. Ves. Pip. 81 (4), 337–344. http://dx.doi.org/10.1016/j.ijpvp.2004.02.015

Krauss, G. (1990). Heat treatment and processing principles. ASM Materials, Park OH, USA, pp. 125–130.

Moon, J., Lee, Ch., Uhm, S., Lee, J. (2006). Coarsening kinetics of TiN particle in a low alloyed steel in weld HAZ: considering critical particle size. Acta Mater. 54 (4), 1053–1061. http://dx.doi.org/10.1016/j.actamat.2005.10.037

NACE ID-182 (1995). Wheel Test Method Used for Evaluation of Film-Persistent Corrosion Inhibitors for Oilfield Applications. NACE, 1440 South Creek Drive, Houston, USA, pp. 1–4.

Saucedo, M.L.M., Komazaki, I.S., Hashida, T., Shoji, T., Lopez, H.V.M. (2003). Aplicación del ensayo miniatura de embutido para la evaluación de la tenacidad a temperaturas criogénicas de aceros inoxidables austeníticos envejecidos isotérmicamente. Rev. Metal. 39 (5), 378–386. http://dx.doi.org/10.3989/revmetalm.2003.v39.i5.350

Vargas, A.B., Albiter, A., Angeles, Ch.C., Hallen, J.M. (2006). Effect of the artificial aging time on the mechanical properties of weldment on API 5L X-52 line pipe steel. Metall. Mater. Trans. A. 37 (9), 2683–2690. http://dx.doi.org/10.1007/BF02586102

Vargas, A.B., Hallen, J. M., Albiter, A. (2007). Effect of the artificial aging on the microstructure of weldment on API 5L X-52 steel pipe. Mater. Charact. 58 (8–9), 721–729. http://dx.doi.org/10.1016/j.matchar.2006.11.004

Vargas, A.B., Hallen, J.M., Albiter, A., Angeles, Ch.C. (2008). Degradation of impact fracture during accelerated aging of weld metal on microalloyed steel. Rev. Metal. 44, 485–492.

Vargas, A.B., Angeles, Ch.C., Albiter, A., Hallen, J.M. (2009). Metallurgical investigation of the aging process on tensile fracture welded joints in pipeline steel. Mater. Charact. 60 (12), 1561–1568. http://dx.doi.org/10.1016/j.matchar.2009.09.007

Vargas, A.B., Solis, R.J., Angeles, Ch.C., Albiter, A., Hallen, J.M. (2011). Deterioration of the corrosion resistance of welded joints in API5L X52 steel isothermally aged. Int. J. Electrochem. Sci. 6 (2), 367–378.

Vargas, A.B., Balvantin, A., Baltazar, A., García, V.F. (2012). On the use of ultrasonic spectral analysis for the characterization of artificially degraded API 5L X52 steel pipeline welded joints. Mat. Sci. Eng. A. 550, 227–234. http://dx.doi.org/10.1016/j.msea.2012.04.064

Watanabe, T., Yamazaki, M., Hongo, H., Tabuchi, M., Tanabe, T. (2004). Effect of stress on microstructural change due to aging at 823 K in multi-layer welded joint of 2.25Cr-1Mo steel. Int. J. Pres. Ves. Pip. 81 (3), 279–284. http://dx.doi.org/10.1016/j.ijpvp.2003.12.017



How to Cite

Vargas-Arista, B., Albiter, A., García-Vázquez, F., Mendoza-Camargo, Óscar, & Hallen, J. M. (2014). Effect of natural aging on the microstructural regions, mechanical properties, corrosion resistance and fracture in welded joints on API5L X52 steel pipeline. Revista De Metalurgia, 50(3), e024. https://doi.org/10.3989/revmetalm.024




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