Analysis of Short-Term Steel Corrosion Products Formed in Tropical Marine Environments of Panama

Abstract

A low-carbon steel A-36 and two conventional weathering steels A-588 and COR-420 exposed at four atmospheric test stations located in (i) Tocumen, an urban site near the Pacific Ocean, (ii) Sherman-Open, (iii) Sherman-Coastal, and (iv) Sherman-Breakwater on the Caribbean coast of Panama. Kinetics of the short-term atmospheric corrosion process and the relationship with exposure time and environmental characteristics of each site were investigated. The atmospheric exposure conditions, particularly the time of wetness, deposition of chloride, and the washing effect of contaminants on the metal surface by rain are of upmost importance in determining the corrosion behaviour and composition of rust. The corrosion products were mainly identified using room temperature and low temperature (80 K) Mössbauer spectroscopy, FTIR, and X-ray powder diffraction. In all samples, γ-FeOOH and α-FeOOH were the main constituents. Maghemite (γ-Fe 2 O 3 ), magnetite (Fe 3 O 4 ), and Akaganeite (β-FeOOH) were also identified.

Outdoor atmospheric corrosion of carbon steel and weathering steel exposed to the tropical‐coastal climate of Thailand

“…Previous studies reported that n > 0.5 indicates a nonprotective rust layer, while n < 0.5 designates a protective rust layer . Another interpretation of the n value is the change of CR at a longer exposure time . For n > 1, CR is accelerated with time.…”

“…The content of goethite was comparable at both stations. In Panama, low‐carbon steel and weathering steels were subjected to tropical‐coastal zones of Pacific Ocean and Caribbean Sea. Airborne pollutions and total TOW were monitored during dry and rainy seasons separately, indicating the wash effect of rain.…”

Carbon steel corrosion: a review of key surface properties and characterization methods

“…Gamma-FeOOH has been identied as corrosion product which was further conrmed through conversion electron Mössbauer spectroscopy (CEMS). Corrosion products of carbon steel (A-36) and weathering steels (A-588 and COR 420) were analysed for atmospheric corrosion through FTIR by Jaen et al 141 The authors conrmed the presence of gamma and alpha-FeOOH, which has been further conrmed through other analytical techniques, such as XRD and Mössbauer spectroscopy. Recently, Chong et al 142 used the synergistic effect of imidazolinium and 4-hydroxycinnamate (organic salt) for corrosion inhibition of mild steel in 0.1 M NaCl and FTIR analysis conrmed the interaction between mild steel surface and 4hydroxycinnamate.…”

A study on the local corrosion behavior and mechanism of electroless Ni–P coatings under flow by using a wire beam electrode

“…Among them, the yellow product was mainly composed of a-FeOOH and g-FeOOH. 29,30 This indicated that WBE was prone to corrosion seriously within eight hours. However, from Fig.…”