Corrosion behaviour of carbon steel in Beibu Gulf tidal zone

Abstract

Corrosion behaviour of carbon steel (CS) exposed in the tidal zone of Beibu Gulf was investigated by experimental method. Q235 CS specimens were designed and exposed for 12 months. The corrosion mechanism of CS was characterised by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-Ray diffraction (XRD). Results show that the corrosion performance of CS can be verified by the formula D = at n . The corrosion products are mainly composed of α-FeOOH, γ-FeOOH, β-FeOOH, Fe 3 O 4 and γ-Fe 2 O 3 . Significantly, Clis an intermediate in the corrosion process and promotes the formation of the characteristic product β-FeOOH.

Effect of Tungsten Inert Gas Remelting on Microstructure and Corrosion Resistance of Q450NQR1 High-Strength Weathering Steel-Welded Joints

“…In high Cl − concentration and low pH environments, the formation of hydroxychloride of iron [β-Fe 2 (OH) 3 Cl] and GRI [Fe 3 II Fe III (OH) 8 Cl − nH 2 O] can be promoted [ 25 , 26 ]. They serve as intermediate products, which are subsequently transformed into β-FeOOH, as shown in the following equation: …”

Analysis of Beibu Gulf tidal zone exposure on properties of carbon steel

“…The field exposure test site is situated at a Beibu Gulf port (21°29 ′ N, 109°05 ′ E) in Beihai City, China, which is located in the subtropical monsoon climate zone, and the environmental condition mentioned in the authors' previous research. 28 Specimens were fixed to the self-made frames and placed in the tidal zone where the dry-wetting time proportion is 5:1, as shown in Figure 2. Three specimens were retrieved for subsequent corrosion behaviour research and mechanical properties test every 30 days, from August 2020 to August 2021.…”

“…Based on previous research result 28 on the corrosion behaviour of CS in the Beibu Gulf tidal zone of our research group, this article investigates the impact of corrosion behaviour on mechanical properties of CS in the Beibu Gulf tidal zone through field exposure test and simulation test. The difference in corrosion behaviour of CS in two environments is discussed and the mechanical properties of corroded specimens are tested to summarise the degradation law which is thought to be related to corrosion behaviour.…”