scholarly journals The Interaction of Biofoulants and Calcareous Deposits on Corrosion Performance of Q235 in Seawater

Materials ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 850
Author(s):  
Jie Zhang ◽  
Zhenhua Yu ◽  
Xia Zhao ◽  
Xiao Lan ◽  
Jiangwei Wang ◽  
...  
Keyword(s):  
Carbon Steel ◽  
Cathodic Protection ◽  
Marine Microorganisms ◽  
Corrosion Performance ◽  
Calcareous Deposits ◽  
Q235 Carbon Steel ◽  
Ocean Conditions

An understanding of the interaction of calcareous deposits and biofoulants on the corrosion performance of steel during the fouling stage is both interesting and necessary. So, the effects of these factors on Q235 carbon steel were investigated and discussed for 20 weeks under real ocean conditions. The results indicate that calcareous deposits are favorable for the attachment of marine microorganisms. However, macroorganisms prefer adhering directly to the substrate. The generations of calcareous deposits have priority over the biofilm attachment under the condition of cathodic protection. Calcareous deposits can prevent steel against corrosion for four weeks without cathodic protection.

scholarly journals The growth mechanism of calcareous deposits under various hydrostatic pressures during the cathodic protection of carbon steel in seawater

RSC Advances ◽  
2017 ◽  
Vol 7 (46) ◽  
pp. 28819-28825 ◽  
Author(s):  
C. J. Li ◽  
M. Du
Keyword(s):  
High Pressure ◽  
Carbon Steel ◽  
Growth Mechanism ◽  
Cathodic Protection ◽  
Crystal Transformation ◽  
Calcareous Deposits

Ca2+ was substituted by Mg2+ in CaCO3 crystallization under high pressure resulting in a crystal transformation from aragonite to dolomite.

The study of the electrochemical properties of zinc-rich coating on the base of water sodium silicate

2019 ◽  
Vol 24 (4) ◽  
pp. 51-58
Author(s):  
Le Hong Quan ◽  
Nguyen Van Chi ◽  
Mai Van Minh ◽  
Nong Quoc Quang ◽  
Dong Van Kien
Keyword(s):  
Carbon Steel ◽  
Electrochemical Properties ◽  
Sodium Silicate ◽  
Cathodic Protection ◽  
Electrochemical Impedance ◽  
Steel Substrate ◽  
Electrical Contact ◽  
Electrochemical Impedance Spectra ◽  
Pure Zinc ◽  
Electric Circuits

The study examines the electrochemical properties of a coating based on water sodium silicate and pure zinc dust (ZSC, working title - TTL-VN) using the Electrochemical Impedance Spectra (EIS) with AutoLAB PGSTAT204N. The system consists of three electrodes: Ag/AgCl (SCE) reference electrode in 3 M solution of KCl, auxiliary electrode Pt (8x8 mm) and working electrodes (carbon steel with surface treatment up to Sa 2.5) for determination of corrosion potential (Ecorr) and calculation of equivalent electric circuits used for explanation of impedance measurement results. It was shown that electrochemical method is effective for study of corrosion characteristics of ZSC on steel. We proposed an interpretation of the deterioration over time of the ability of zinc particles in paint to provide cathodic protection for carbon steel. The results show that the value of Ecorr is between -0,9 and -1,1 V / SCE for ten days of diving. This means that there is an electrical contact between the zinc particles, which provides good cathodic protection for the steel substrate and most of the zinc particles were involved in the osmosis process. The good characteristics of the TTL-VN coating during immersion in a 3,5% NaCl solution can also be explained by the preservation of corrosive zinc products in the coating, which allows the creation of random barrier properties.

scholarly journals Design an Epoxy Coating with TiO2/GO/PANI Nanocomposites for Enhancing Corrosion Resistance of Q235 Carbon Steel

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2629
Author(s):  
Shimin Chen ◽  
Bo Li ◽  
Rengui Xiao ◽  
Huanhu Luo ◽  
Siwu Yu ◽  
...  
Keyword(s):  
Carbon Steel ◽  
Photocurrent Density ◽  
Photoelectrochemical Performance ◽  
Q235 Steel ◽  
Protective Barrier ◽  
Barrier Coating ◽  
Pani Composite ◽  
Steel Protection ◽  
Q235 Carbon Steel

In this work, a ternary TiO2/Graphene oxide/Polyaniline (TiO2/GO/PANI) nanocomposite was synthesized by in situ oxidation and use as a filler on epoxy resin (TiO2/GO/PANI/EP), a bifunctional in situ protective coating has been developed and reinforced the Q235 carbon steel protection against corrosion. The structure and optical properties of the obtained composites are characterized by XRD, FTIR, and UV–vis. Compared to bare TiO2 and bare Q235, the TiO2/GO/PANI/EP coating exhibited prominent photoelectrochemical properties, such as the photocurrent density increased 0.06 A/cm2 and the corrosion potential shifted from −651 mV to −851 mV, respectively. The results show that the TiO2/GO/PANI nanocomposite has an extended light absorption range and the effective separation of electron-hole pairs improves the photoelectrochemical performance, and also provides cathodic protection to Q235 steel under dark conditions. The TiO2/GO/PANI/EP coating can isolate the Q235 steel from the external corrosive environment, and may generally be regarded a useful protective barrier coating to metallic materials. When the TiO2/GO/PANI composite is dispersed in the EP, the compactness of the coating is improved and the protective barrier effect is enhanced.

Sign in / Sign up

Export Citation Format

Share Document