Significance of coplanar macrocells to corrosion in concrete-embedded steel

Journal Article · Mon Mar 01 00:00:00 EST 1999 · Corrosion

DOI:https://doi.org/10.5006/1.3283994· OSTI ID:349907

Rodriguez, P ^[1]; Ramirez, E ^[2]; Feliu, S; Gonzalez, J A ^[3]; Lopez, W ^[4]

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1. Univ. Autonoma de Nuevo Leon (Mexico)
2. Inst. de Investigacion Tecnologica Industrial y de Normas Tecnicas, Lima (Peru)
3. Centro Nacional de Investigaciones Metalurgicas, Madrid (Spain)
4. CEMEX, S.A. Monterrey (Mexico)

The influence of microcells and galvanic macrocells on the corrosion kinetics of concrete-embedded steel was investigated experimentally. Nine stainless steel/carbon steel coplanar macrocouples in cathodic-to-anodic ratios of 0.02 to 50 were cast in concrete slabs made from cement, sand, and water in a 1:3:0:5 proportion plus 2% calcium chloride (CaCl{sub 2}) per cement weight. Corrosion potential (E{sub corr}), galvanic current (i{sub g}), polarization resistance (R{sub p}), and impedance measurements from 100 kHz to 0.01 Hz were made for the two metals, coupled and uncoupled. i{sub g} data provided by a zero resistance ammeter led to potentially underestimated corrosion rates for anodic areas, whereas R{sub p} measurements provided fairly reliable corrosion rates. Macrocells polarized anodic areas very slightly at points where an anodic and a cathodic process took place simultaneously.

• Sponsoring Organization: USDOE
• OSTI ID: 349907
• Journal Information: Corrosion, Vol. 55, Issue 3; Other Information: PBD: Mar 1999
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ELECTROCHEMICAL CORROSION
CARBON STEELS
STAINLESS STEELS
REINFORCED CONCRETE
KINETICS
CALCIUM CHLORIDES
ELECTRIC CURRENTS
ELECTRIC POTENTIAL
IMPEDANCE