Corrosion Behavior Of Steel Research Articles

Galvanic corrosion of Q345 steel in seawater under varying dissolved oxygen conditions

The galvanic coupling corrosion behaviour of Q345 steel in seawater with different dissolved oxygen contents (DOC) was investigated in this paper by using self-designed detachable electrodes fabricated as chain electrodes, and by using immersion and electrochemical methods in combination with macroscopic and microscopic corrosion morphology. Compared with the corrosion of the chain electrode in the non-electrically connected state, in the electrically connected state, the corrosion current densities of the corresponding electrodes were smaller and the Rp values were larger when the DOC was 8.50, 7.50 and 5.50 mg L−1, indicating that the corrosion reaction was mainly a self-corrosion reaction when the DOC was 8.50, 7.50 and 5.50 mg L−1. When DOC is 9.50 and 6.50 mg L−1, the corrosion current density of the corresponding electrode was larger, the Rp value was smaller, the corrosion products on the surface of the electrode had a loose structure, the relative content of iron was higher, and the corrosion reaction was mainly galvanic coupling corrosion reaction.

Effect of copper content on the microstructure and electrochemical corrosion behavior of laser cladding 316L stainless steel coating

Effect of copper content on the microstructure and electrochemical corrosion behavior of laser cladding 316L stainless steel coating

Experimental and computational investigation on corrosion behavior of carbon steel in the presence of Ferula assa-foetida leaf extract

Experimental and computational investigation on corrosion behavior of carbon steel in the presence of Ferula assa-foetida leaf extract

Effect of martensite morphologies on corrosion in sea water of X52 dual phase steel

This study investigates the effect of martensite morphologies on the corrosion behavior of X52 dual-phase steel when exposed to seawater. The steel underwent three different heat treatments: direct quenching (DQ), step quenching (SQ), and intermediate quenching (IQ) at 760°C and 800°C, in order to achieve varying martensite structures. The direct quenching (DQ) treatment resulted in the formation of fine martensite, evenly distributed throughout the ferrite matrix. The intermediate quenching (IQ) treatment led to the formation of martensite along the ferrite/ferrite grain boundaries. In contrast, the step quenching (SQ) treatment produced a banded morphology of martensite and ferrite. We studied the corrosion behavior using Tafel polarization techniques in a saltwater solution. We observed that the morphology and quantity of martensite influence the corrosion behavior. The corrosion rate of the direct quenching (DQ) treatment was lower compared to that of the step quenching (SQ), intermediate quenching (IQ), and the initial untreated state.

Corrosion of metals in calcium nitrate based phase change material

AbstractPhase change materials are assumed to be a promising way of a storage of the low-potential heat. In the paper, the corrosion behaviour of carbon steel, CuZn37 brass and aluminium was studied in the assumed phase change medium at 50 °C and 60 °C. The medium was a eutectic mixture of 26.09 wt% water, 63.34 wt% calcium nitrate, 10.57 wt% potassium nitrate with fusion temperature of 37.85 °C. Corrosion rate was studied via mass loss and the steel specimens were analysed after the study. It was found that even though the corrosion rate of carbon steel and aluminium is small (4.26 mg cm−2 year−1 and 1.19 mg cm−2 year−1, respectively, at 50 °C), the metals are susceptible to pitting corrosion. Brass has the lowest corrosion rate from the studied metals (0.88 mg cm−2 year−1 at 50 °C); however, it is a subject of selective corrosion with zinc preferentially dissolved. None of the metals studied is suitable for the use in the phase change materials.

Electrochemical behavior of 250-grade maraging steel by using Cascabela Thevetia as an organic inhibitor

ABSTRACT The Cascabela Thevetia (CT) plant, from the Apocynaceae family, is known for its use in traditional medicine across Central and South America and tropical Asia. This study examines the effect of CT leaf extract on the corrosion behavior of maraging steel in a 1 M H2SO4 solution. The addition of leaf extract (10 to 50 ml) reduced the corrosion rate (CR), with higher concentrations leading to greater inhibition efficiency, from 64.04% to 88.35%. Same trend is observed with rising temperatures. Electrochemical impedance spectroscopy (EIS) revealed that R ct (charge transfer resistance) increases with rising inhibitor concentration, signifying enhanced ‘blanketing’ properties of the protective film as the inhibitor concentration increases. Additionally, the calculated free energy value i.e. Δ G ∘ ≤ 20 KJ/mol suggests that physisorption is the dominant adsorption process. The reduction in the randomness of inhibitor molecules is evident from the calculated Δ S ∘ . Moreover, a positive Δ H ∘ value indicates that the inhibition process is endothermic. SEM analysis confirmed that the inhibitor reduced surface porosity, resulting in a smoother surface.

Creep Properties and Corrosion Behavior of TP347H Stainless Steel with Al in Molten Carbonate Salt.

Molten carbonate salts are a promising candidate for next-generation concentrated solar power technology owing to their excellent heat storage and heat transfer properties. This represents overcoming several problems that structural materials exhibit, including severe corrosion and high-temperature creep. Alloys with an aluminum element are alternatives in this regard as they are highly resistant to corrosive environments. In this paper, the corrosion behavior in molten carbonates (Li2CO3-Na2CO3-K2CO3) and creep properties of TP347H with different aluminum contents at 650 °C were studied. The results demonstrated that the alloy corrosion rate was reduced via Al addition. The alloy with 2.5 wt.% Al exhibited the lowest corrosion rate: ~25% lower than that without Al after 1000 h of corrosion. With increasing Al content, the inner corrosion layer of the alloys transformed from a Cr-containing oxide layer to a Cr-Al-containing composite oxide layer. The addition of Al promoted the formation of a layer of continuous and dense LiFeO2 product on the alloy surface during early corrosion stages, which prevented the carbonate from coming into direct contact with the substrate. After 1000 h of corrosion, the surface of the alloy is mainly composed of LiFeO2 and LiCrO2. Compared to TP347H, the added Al element enhanced the strength and elongation of TP347H at 650 °C. The TP347H containing 2 wt.% Al exhibited the best high-temperature tensile properties. When the stress was 110 MPa, the lowest steady-state creep rate of the alloy containing 2 wt.% Al was 3.61 × 10-6, and the true stress index was 5.791. This indicates that the creep mechanism was a dislocation climb assisted by lattice diffusion.

Correction: Effects of Alternating Current Corrosion Behavior of X80 Pipeline Steel under Delaminated Coating Defects

Correction: Effects of Alternating Current Corrosion Behavior of X80 Pipeline Steel under Delaminated Coating Defects

Influence of incubation time on corrosion behavior of EH36 steel by marine Halomonas titanicae in aerobic environments

Influence of incubation time on corrosion behavior of EH36 steel by marine Halomonas titanicae in aerobic environments

Influence of arc energy on the microstructure and corrosion behavior of ER2209 duplex stainless steel deposited on Q345B low-alloy steel by GMAW

In order to eliminate the complex effects of thermal cycling and the thermal effects of the next pass on multi-layer multi-pass welding of low-alloy steel and duplex stainless steel, ER2209 welding wire was single-layer single-pass deposited on the surface of Q345B hot-rolled plate by gas metal arc welding (GMAW). The microstructure and corrosion resistance of welded joints were studied by different arc energies. The results showed that the arc energy had a significant impact on the “tongue-shaped” morphology and the width of heat affect zone in the welded joint, which in turn affected the corrosion performance of the welded joints. Due to the least distribution of “tongue-shaped” morphology and minimum width of heat affected zone in the welded joint with arc energy of 0.645kJ/mm, it owned the best corrosion resistance. The weld metals of the welded joints were composed of ferrite and austenite phases. The ferrite phases were distributed along grain boundaries and intergranular. As the heat input increases, the distribution of ferrite phase along grain boundaries gradually decreased. The corrosion products and corrosion morphology of the welded joint were also investigated and the corrosion mechanism was discussed in detail. The research results of this article provide a theoretical basis for improving the corrosion performance of multi-layer multi-pass welded joints of low-alloy and duplex stainless dissimilar steels.

Corrosion behavior of a high-carbon austenitic stainless steel with ultrafine Cr23C6 precipitates in molten FLiNaK salt

Corrosion behavior of a high-carbon austenitic stainless steel with ultrafine Cr23C6 precipitates in molten FLiNaK salt

Comparison of the short-term corrosion behavior and mechanism of 40CrNiMoA steel in the marine atmospheric zone and the splash zone

Comparison of the short-term corrosion behavior and mechanism of 40CrNiMoA steel in the marine atmospheric zone and the splash zone

Influence of stress on corrosion behavior and evolution model of Q235 steel in marine environments

The corrosion failure mechanism of Q235 steel under different stresses in simulated marine environment was investigated. The corrosion products of Q235 steel under different stresses are characterized. Additionally, electrochemical experiments and finite element simulations were conducted to examine the corrosion behavior of Q235 steel under various stress conditions. Stress promotes the corrosion failure of Q235 steel and accelerates the generation and transformation of corrosion products. Different stress levels lead to distinct stress corrosion mechanisms, with lower stress levels increasing sensitivity to corrosion. Elevated levels of stress result in stress concentration in dislocation defects, leading to more severe localized corrosion. A model for the evolution of stress corrosion failure has been established, revealing that the corrosion behavior at different stress levels is not strictly independent and can transition from low to high stress conditions under certain circumstances. Furthermore, it was observed that even at low stresses, there can be occurrences of stress concentrations leading to localized corrosion.

Study on the localized flow-accelerated corrosion of EH32 steel based on wire beam electrodes and EIS measurements

This study investigated the flow-accelerated corrosion (FAC) behaviour of EH32 steel using a submerged impingement jet system. The dynamic development process of FAC was monitored in real-time by combining wire beam electrodes (WBE) and EIS measurements. The distribution of the flow field and mass transfer rates were calculated through CFD simulation. The results show that the WBE technique effectively visualizes the dynamic development process of FAC under non-uniform flow fields. Inhomogeneous distribution of the flow field and variations in mass transfer rates were identified as the primary factors influencing the early stages of FAC development. An accumulation of anolyte in the centre of the electrode under the influence of the flow field led to the evolution of this region into the main anodic area, fostering macro-cell corrosion between the surrounding region. In the later stages of FAC, the rust layer emerged as a critical factor influencing the FAC behaviour. Discrepancies in wall shear stress and corrosion across various areas result in diverse localized characteristics of the rust layer on the electrode surface. The inhibition of the mass transfer process by the rust layer mitigates macro-cell corrosion. The impact of the flow field and the rust layer on the transfer of the anolyte is the primary factor driving the development of "flow mark" corrosion patterns in the central area and pitting corrosion patterns in the edge area.

Atmospheric Corrosion Behavior of Mild Steel with Different Cooling Modes After Austenitization

Atmospheric Corrosion Behavior of Mild Steel with Different Cooling Modes After Austenitization

Investigation of corrosion behavior of 5Cr steel in CO₂-silty sand environment: Effects of hydrodynamic impact angles

This study investigates the influence of impact angles on the corrosion behavior of 5Cr steel in a CO2-silty sand environment through hydrodynamics analysis. The primary cause of degradation in 5Cr steel is the combined effect of the mechanical damage to the corrosion product film by silty sand particles and corrosive environment. The severity of damage to the corrosion product film on the 5Cr steel surface caused by silty sand particles at different impact angles, from highest to lowest, is 45°, 90°, and 0°. At an impact angle of 45°, the silty sand exerts equal tangential and normal stresses on the corrosion product film, compromising its integrity and requiring more Cr(OH)3 for repair and stabilization, resulting in the most severe localized pitting corrosion. At impact angles of 0° and 90°, the silty sand exerts only tangential stress and normal stress on the corrosion product film, respectively. The imbalance between normal and tangential stresses at these angles results in shallower and more limited removal of corrosion products, making the destructive effect less significant than at a 45° impact angle.

Corrosion and mechanical behavior of a new Q450 weathering steel

Weather-resistant steel represents a significant advancement in addressing corrosion challenges. Several types of steel with enhanced weather resistance have already been developed and manufactured. Weathering steel has shown excellent anti-corrosion ability over conventional structural steel. However, research on the corrosion and mechanical behavior of this type of steel after corrosion damage is still limited. Therefore, this paper conducts a detailed experimental investigation of the corrosion behavior and tensile strength of a new Q450 weathering steel after an accelerated corrosion test. Several scanning techniques were employed to examine the development of corrosion damage in the new Q450 weathering steels after being subjected to different corrosion times. Vickers hardness and velocity intensity of the corroded specimen were obtained to reveal the corrosion behavior of the Q450 steel. Based on the test data, predictive models were developed to predict the pit size and mechanical properties of Q450 steel after corrosion damage. The results suggest that, as the corrosion time increases, the types and amounts of corrosion products change significantly, which causes the passivation film to become much denser. Meanwhile, the mechanical properties are degraded by the increasing corrosion damage. Ultimately, the proposed predictive models are proven to be accurate and reliable.

Effect of temperature on the electrochemical corrosion behavior of X52 pipeline steel in NS4 simulated solution

In this study, the electrochemical corrosion performance of both the base material and welded joint of X52 pipeline steel was analyzed at various temperatures (room temperature-RT, 30 °C, 50 °C, and 80 °C) using microscopic characterization techniques and electrochemical methods in a simulated soil solution (NS4). Additionally, the influence of temperatures on the electrochemical corrosion behavior of the X52 pipeline steel base material and welded joint was examined. The findings indicate that the open circuit potential (Eocp) of the base material and welded joint shifts in the negative direction with increasing temperature. The corrosion current density increased from 30.7 to 110.2 μA∕cm2 and from 19.5 to 100.2 μA∕cm2, respectively, while the polarization resistance dropped from 637.3 to 272.6 Ω•cm2 and from 961.3 to 360.7 Ω•cm2. Notably, anodic dissolution controls the corrosion process of the base material and welded joint of X52 pipeline steel at room temperature. Furthermore, the charge transfer resistance (Rt) of the base material and welded joint gradually decreases with increasing temperature, and the corrosion process transforms into cathodic diffusion control. Additionally, the welded joint of X52 pipeline steel exhibits superior corrosion resistance to that of the base material at the same temperature.

Enhancing Corrosion Resistance of Type 316L Stainless Steel in Marine Environments: Role of Surface Roughness and Organic Acid Passivation

Stainless steel is widely used in marine environments due to its excellent corrosion resistance properties. However, recent occurrences of corrosion issues related to Type 316L stainless steel in marine atmospheric environments have led to concerns regarding the suitability of Type 316L stainless steel material selection according to international standards. Factors such as surface roughness and passivation treatments can significantly affect the corrosion behavior of stainless steel in marine atmospheres. In particular, the surface roughness of conventional stainless steel piping can lead to corrosion in marine atmospheric environments when exposed for extended periods. Either option requires improving the surface roughness or applying passivation treatments to enhance corrosion resistance.This study examines the effect of surface roughness on the corrosion resistance of Type 316L stainless steel in a marine environment using potentiodynamic polarization and accelerated corrosion tests. In addition, the impact of organic acid passivation on the corrosion behavior of stainless steel in a marine atmosphere is investigated. Surface roughness was controlled by mechanical polishing, while organic acid passivation was achieved using a solution containing citric acid, phosphoric acid, and hydrogen peroxide. Electrochemical measurements and surface characterization techniques were employed to assess the corrosion resistance of the specimens. The results demonstrate that surface roughness and organic acid passivation significantly impact the corrosion resistance of stainless steel in a marine atmosphere. Understanding the synergistic effects of these factors is crucial for enhancing the durability and performance of stainless steel components in marine applications.

Effect of Bentonite Properties on Corrosion Behavior of Carbon Steel

Geological disposal is being considered as a disposal method for liquid waste resulting from nuclear power generation. In geological disposal, liquid waste and glass materials are melted together and solidified in an overpack (metal container), and a buffer material is compacted between the overpack and the bedrock. Carbon steel is as a candidate for overpack material and bentonite as a buffer materialin Japan. Overpack materials are required to be safe and reliable over a very long period, and their corrosion behavior and long-term corrosion resistance have been investigated before. However, most of these researches have been conducted in environments where oxygen is fully consumed, and the corrosion behavior and resistance during transient periods have not been fully clarified. In this study, the effects of bentonite properties on the corrosion behavior of carbon steel in compacted bentonite were investigated by electrochemical methods in order to clarify the corrosion behavior of carbon steel during the transient period. An iron wire grinded with sandpapers was used as the sample. The amount of bentonite was weighed to achieve the specified compacted density, and firstly approximately one-half of the amount was filled into a titanium compacted vessel. The iron wire was then set on the bentonite and the remaining bentonite was filled into the vessel using a hydraulic press. The properties of the bentonite were adjusted from 0.9 Mg/m3 to 1.8 Mg/m3 with the compaction density when packed. The titanium vessel was then immersed in a 0.1 mol/L NaCl solution and depressurized at room temperature. The solution was supplied to the cell through a filter on the side of the cell. Polarization and electrochemical impedance measurements were performed in a three-electrode system under open air. The test solution was 0.1 mol/L NaCl solution, a saturated KCl/Ag/AgCl electrode (SSE) was used as the reference electrode, and a platinum wire as the counter electrode. Polarization measurements were conducted by polarizing in the anodic and cathodic directions from the immersion potential at a scanning rate of 0.5 mV/sec. The polarization measurements of an iron wire were also performed in the same solution for comparison. Electrochemical impedance was measured at 24 and 48 hours after immersing the titanium vessel in the test solution. Polarization curve of iron wire in bentonite with a compressibility density of 1.5 Mg/m3 were compared with that in the solution. A clear diffusion-limiting current of oxygen was observed in the polarization curve of iron wire in the solution, whereas it was unclear for iron wire in bentonite. This result is attributed to the influence of water reduction reaction in a cathodic region. On the other hand, in the anodic region, the anodic current of iron in bentonite was about two orders of magnitude lower than that in the solution. This indicates that electrochemical measurements are possible in bentonite as well as in solution, but the influence of compacted bentonite is not small. Electrochemical impedance characteristic of the iron wire in bentonite with a compressive density of 1.6 Mg/m3 showed one time constant after 25 hours of immersion and two time constants after 48 hours, respectively.The diameter of the capacitive semicircles decreased with immersion time. The titanium vessel immersed for 48 hours was opened and the surface of the iron wire was visually observed. As a result, corrosion products were observed. These results suggest that the test solution penetrated into the compacted bentonite after at least 25 hours, and that corrosion progressed to form corrosion products on the electrode surface by 48 hours. Curve fitting was performed on the obtained impedance spectra, assuming the two equivalent circuits. As a result, it was confirmed that the polarization resistance at the electrode surface decreases with time.