Vol. 15 No. 02 (2025): Journal of Materials & Construction
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JOURNAL OF MATERIALS & CONSTRUCTION

ISSN: 2734-9438

Website: www.jomc.vn

Evaluation of the effectiveness of molybdate-based coating on reinforcing steel during the pre-construction phase of offshore projects

Dang Thi Thu Hien , Le Van Toan , Nguyen Quy Thanh , Dang Minh Duc

Keywords:

Ammonium heptamolybdate (AHM)
Reinforcing steel
Corrosion inhibition
Offshore construction
Electrochemical testing

Abstract

The corrosion behavior of carbon steel in 3.5 wt.% NaCl solution and the inhibition performance of ammonium heptamolybdate (AHM)/sodium carbonate (Na₂CO₃) were investigated using electrochemical techniques (Tafel, EIS), gravimetric measurements, and SEM/EDS analyses. The unprotected steel showed rapid corrosion, as indicated by high Icorr, low Rcorr, and severe surface damage. The addition of AHM/Na₂CO₃ significantly reduced corrosion, with the In3 system (1.5 g/L AHM + 1.5 g/L Na₂CO₃) exhibited the best performance In3 achieved the lowest Icorr, the highest resistance, and an inhibition efficiency above 95%. Gravimetric measurements confirmed long-term stability, while SEM/EDS revealed a compact and adherent protective film that effectively blocked chloride penetration. These results highlight In3 as an highly effective and sustainable corrosion inhibitor for carbon steel in chloride environments, suitable for protecting steel during transportation to offshore construction sites.

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How to Cite

Dang Thi Thu Hien, Le Van Toan, Nguyen Quy Thanh, & Dang Minh Duc. (2025). Evaluation of the effectiveness of molybdate-based coating on reinforcing steel during the pre-construction phase of offshore projects. JOURNAL OF MATERIALS & CONSTRUCTION, 15(02). https://doi.org/10.54772/jomc.v15i02.1123

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