Corrosion Resistance Of Steel Research Articles

Effects of Nb on Creep Properties and Hot Corrosion Resistance of New Alumina-Forming Austenitic Steels at 700 °C

Effects of Nb on the creep resistance and hot corrosion behavior of the Fe-25Cr-35Ni-2.5Al-xNb (x = 0, 0.6, 1.2) Alumina-Forming Austenitic stainless steels (AFA steels) at 700 °C were investigated. The addition of Nb promoted the precipitation of both nanoscale NbC and γ′-Ni3(Al, Nb) phases, which exhibited very low coarsening rate constants. The nanoscale NbC and γ′-Ni3(Al, Nb) phases effectively impeded the migration of dislocations and led to an improvement in creep performance of the Nb-addition AFA steel. The corrosion of AFA steels in Na2SO4-25%K2SO4 at 700 °C was primarily driven by an “oxidation-sulfidation” mechanism. The addition of Nb, serving as a third element, facilitated the formation of protective Cr2O3 and Al2O3 films, which improved the hot corrosion resistance performance. However, the formation Nb2O5 was found to compromise the compactness of the oxide film, which adversely affected the corrosion resistance.

Assessing the anti-corrosive properties of 2,6-bis-furan-2ylmethylene-cyclohexanone as a carbon steel inhibitor in 0.5M HCl solution

This study investigated the effectiveness of 2, 6-bis-furan-2ylmethylene-cyclohexanone as a corrosion inhibitor for carbon steel in a 0.5 M HCl solution through a combination of experimental and theoretical methodologies. Firstly, the study employs weight loss analysis, revealing that the presence of 0.10 ppm of the inhibitor leads to a significant inhibition efficiency (IE) of 93.40 % against corrosion in acidic conditions. Polarization studies further elucidate the inhibitor's role, indicating its function as a cathodic inhibitor and its influence on the corrosion kinetics of carbon steel. Moreover, alternating current impedance spectra are analysed to gain insights into the electrical behaviour of the protective film formed by the inhibitor and its consequent impact on the corrosion resistance of carbon steel. The composition of this protective film, comprising both carbon steel and 2, 6-bis-furan-2ylmethylene-cyclohexanone was confirmed using advanced imaging techniques such as scanning electron microscopy (SEM) and atomic force microscopy (AFM). In addition to experimental investigation, a theoretical approach was also employed using Density Functional Theory (DFT) to predict the behaviour of the inhibitor at the molecular level on the surface of carbon steel. This theoretical framework facilitates a deeper understanding of the interactions between inhibitor molecules and the carbon steel surface, offered insights into the mechanisms underlying the corrosion inhibition process. By utilizing quantum chemical calculations, the study aims to elucidate the inhibitory properties of 2,6-bis-furan-2ylmethylene-cyclohexanone against corrosion of carbon steel, thereby contributing to the development of effective corrosion inhibition strategies.

Effect of Cerium on Inclusion Evolution and Pitting Corrosion of Nb-Microalloyed Steel.

Nb-microalloyed steels are widely used in construction engineering fields due to their excellent mechanical properties, but they face serious corrosion problems in service environments. Pitting corrosion is the severest form of corrosion, and the types of inclusions are the leading cause to induce pitting corrosion. A new strategy is proposed to enhance the corrosion resistance of steels by achieving a beneficial transformation of inclusions with Ce treatment. In this paper, two types of Nb-microalloyed steels (0% Ce and 0.0058% Ce steel) were prepared to study the modification effect on inclusions in industrial production. The spherical CaS•C12A7 inclusions were modified to smaller ellipsoidal Ce2O2S inclusions, and the proportion of inclusions (0-2 μm) increased significantly from 27 to 66%, while large inclusions (>6 μm) disappeared. A kinetic model of inclusion evolution was established. The results of electrochemical tests indicated that the corrosion potential was positively shifted, and the corrosion current was reduced after Ce treatment. Additionally, the number of defects in the passivation film was decreased, and the corrosion resistance of the steel was significantly improved. The addition of Ce changed the types of inclusions and reduced the number of pitting nucleation points, which led to a remarkable reduction in the number and size of pitting pits. The mechanism of pitting corrosion induced by different types of inclusions was further investigated, and a pitting corrosion model was modeled based on the immersion experiments. Research results provide theoretical support for enhancing the corrosion resistance of steel.

Exploring the Anti-Corrosion, Photocatalytic, and Adsorptive Functionalities of Biogenically Synthesized Zinc Oxide Nanoparticles

This study reported the synthesis of ZnO nanoparticles (ZnO NPs) using Cucurbita pepo L. seed extract and explored their multifunctional properties such as anti-corrosion, photocatalytic, and adsorption capabilities. The synthesized ZnO NPs were characterized by Fourier-transform infrared spectroscopy (FTIR) to identify their functional groups, thermogravimetric analysis (TGA) to assess their thermal stability, transmission electron microscopy (TEM), and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) to determine their size, morphology, and elemental composition. The characterization of biofabricated ZnO NPs revealed an average particle size of 32.88 nm; however, SEM displayed a tendency for the particles to agglomerate. Furthermore, the X-ray diffraction (XRD) and EDX analysis confirmed the NPs as ZnO, matching patterns reported in the literature. In this study, the potential of the biogenic ZnO NPs was explored for multifunctional applications. Zinc oxide nanoparticles exhibited a higher capacity for adsorbing hydrogen sulfide (H2S) compared to bulk zinc oxide, mostly because of their larger surface area. In addition, electrochemical studies demonstrated a substantial enhancement in the corrosion resistance of mild steel in a 1.0 M HCl solution. ZnO NPs also demonstrated remarkable photodegradation effectiveness, reducing 75% of methyl orange in 60 min under sun-light irradiation. This implies that they could be used to remediate organic pollutants (organic dyes) from wastewater.

Effects of ultrasonic impact on surface characterization of S355 steel welded joint

The effects of ultrasonic impact treatment (UIT) on the residual stress, the microhardness, the nano-hardness, the microstructure, the electrochemical corrosion resistance, the corrosion morphology, and the chemical composition of the S355 steel welded joints were investigated. In addition, the mechanism of improving the electrochemical performance of the S355 steel welded joints by the UIT was studied. The results showed that the UIT could significantly improve the electrochemical corrosion resistance of the S355 steel welded joints. The corrosion potential and impedance were increased, and the corrosion current density was decreased with the increasing of the UIT time. According to the corrosion morphology, it was observed that after the UIT, the number of corrosion pits in the welds and heat-affected zones of S355 steel welded joints significantly decreased, along with reductions in the depth and size of the pits. After the UIT, the grain size of the S355 steel welded joints was refined, and both the microhardness and the nano-hardness of the welded joint were increased, which indicated that substantial plastic deformation occurred on the S355 steel welded joint. Moreover, the UIT could significantly reduce and transform residual tensile stress into residual compressive stress in areas adjacent to the welds, and the residual compressive stress could be increased with the increasing of the UIT time. It can be concluded that the introduced compressive residual stress, the grain refinement, and the generated plastic deformation were the main factors in improving the electrochemical corrosion resistance.

Reinforcing steels in low-carbon mortars subjected to chloride attack and natural carbonation: Contradictory trends in passivation ability and corrosion resistance

After a 7-year exposure to simulated marine environments with chloride attack and natural carbonation, the passivation ability and corrosion resistance of carbon steel and 2304 duplex stainless steel in two types of low-carbon mortars, designed with alkali-activated slag and Bayer red mud, were investigated, which were compared with those observed in ordinary Portland cement (OPC) mortar. Although a reduced passivation ability was confirmed for steels in the low-carbon mortars, an improved corrosion resistance was highlighted after long-term exposure. Accordingly, the underlying mechanisms for the detrimental impacts and beneficial effects on the corrosion resistance of steels provided by these low-carbon mortars were discussed in terms of pore solution chemistry, pore structure as well as electrical resistivity, which will shed new lights on the design of novel cementitious materials with low carbon footprint and high corrosion protection.

Influence of different methods of surface treatment on corrosion resistance of low-alloy steel

The influence of mechanical methods of surface treatment (polish and polish with the next strengthening by high-frequency mechanical pinning, HFMP) on the corrosion resistance of low-alloy steel 15HSND were presented. The deficiencies of surface strengthening by HFMP with one impact peen were analyzed, and an instrument in which shock elements are situated in a few rows was suggested. Speed of HFMP for the surfaces 35 sm2/min was recommended. The differences in structure and microhardness of near-surface layers of 15HSND steel with polished surface and the polished surface with next strengthening by HFMP were established after investigations in the salt frog chamber and moisture chamber during 1200 hours. Application of HFMP technology increases of corrosion resistance of steel: corrosion rate after neutral salt fog decreased from 2,543 mm/year on the polished surface to 2,096 mm/year after HFMP treatment, and after increased humidity and temperature, from 0,104 mm/year to 0,080 mm/year.

Corrosion Behavior of Ferritic 12Cr ODS and Martensitic X46Cr13 Steels in Nitric Acid and Sodium Chloride Solutions.

This paper presents corrosion resistance results of a 12Cr ferritic ODS steel (Fe-12Cr-2W-0.5Zr-0.3Y2O3) fabricated via a powder metallurgy route as a prospective applicant for fuel cladding materials. In a spent nuclear fuel reprocessing facility, nitric acid serves as the primary solvent in the PUREX method. Therefore, fundamental immersion and electrochemical tests were conducted in various nitric acid solutions to evaluate corrosion degradation behavior. Additionally, polarization tests were also performed in 0.61 M of sodium chloride solutions (seawater-like atmosphere) as a more general, all-purpose procedure that produces valid comparisons for most metal alloys. For comparison, martensitic X46Cr13 steel was also examined under the same conditions. In general, the corrosion resistance of the 12Cr ODS steel was better than its martensitic counterpart despite a lower nominal chromium content. Potentiodynamic polarization plots exhibited a lower corrosion current and higher breakdown potentials in chloride solution in the case of the ODS steel. It was found that the corrosion rate during immersion tests was exceptionally high in diluted (0.1-3 M) boiling nitric acid media, followed by its sharp decrease in more concentrated solutions (>4 M). The results of the polarization plots also exhibited a shift toward more noble corrosion potential as the concentrations increased from 1 M to 4 M of HNO3. The results on corrosion resistance were supported by LSCM and SEM observations of surface topology and corrosion products.

The Influence of Slide Burnishing on the Technological Quality of X2CrNiMo17-12-2 Steel.

Metal products for the metallurgical and machinery industries must meet high requirements in terms of their performance, including reliability, accuracy, durability and fatigue strength. It is also important that materials commonly used to manufacture such products must meet specific requirements. Therefore, various techniques and technologies for modifying the surface layer are becoming more and more widely used. These include burnishing, which may be dynamic or static. This article studies the process of slide burnishing of surfaces of cylindrical objects. The burnishing was performed using a slide burnisher with a rigid diamond-tipped clamp on a general-purpose lathe. The tests were performed for corrosion-resistant steel X2CrNiMo17-12-2. The aim of the research was to determine the impact of changes in burnishing conditions and parameters-feed rate, burnisher depth and burnishing force at a constant burnishing speed-on the surface roughness and hardness. Additionally, the microstructure was assessed in the critical areas: the surface and the core. Another phenomenon observed was surface cracking, which would be destructive due to the occurrence of indentation. In the paper, it was stated that the microstructure, or rather the grains, in the area of the surface layer was oriented in the direction of deformation. It was also observed that in the area of the surface layer, no cracks or other flaws were revealed. Therefore, slide burnishing not only reduces the surface roughness but hardens the surface layer of the burnished material.

Fracture surface topography measurements analysis of low-alloyed corrosion resistant steel after bending-torsion fatigue tests

In this paper, an assessment of a topography measurement method for fracture surfaces of 10HNAP steel after bending-torsion fatigue tests was performed. Surface roughness was measured by using a non-contact Focus Variation Microscopy (FVM) technique in which the non-measured points (NMPs) and outliers (spikes) were removed by the application of general methods. The results revealed, that the optical measurement method introduced variations in the high-frequency errors, considered as noise within the selected bandwidth. Therefore, the minimization of the high-frequency noise (HFN) was proposed based on an extensive examination of ISO 25178 roughness parameters. Additionally, a general S-filter was applied, as recommended by international standards and commercial software. It was used to identify and remove noise from the measured data after pre-processing. Consequently, levelling and eliminating of NMPs and spikes was successfully performed. Subsequently, the results obtained by using various filters were compared to further assess the impact of different filtration bandwidths. Finally, the proposed procedure was validated by implementing different general functions, such as autocorrelation (ACF), power spectral densities (PSD), and texture direction (TD). It was concluded, that coupled characteristics, including profile and areal measurements, should be studied simultaneously since they are necessary to analyze the fracture surfaces comprehensively.

Copper Alloying Improves the Microbiologically Influenced Corrosion Resistance of Pipeline Steel

Microbiologically influenced corrosion (MIC) has long been a critical issue due to its potential to cause severe damage to equipment and the associated risk of operational failures, leading to significant financial losses. This study investigates the resistance to MIC caused by sulfate-reducing bacteria (SRB) in four types of pipeline steel materials, which are soon to be introduced to the market. Two of these materials have been alloyed with copper during the metallurgical process. The uniform corrosion rates of the copper-alloyed materials were found to be 0.012 ± 0.002 mm/y, 0.060 ± 0.01 mm/y, and 0.010 ± 0.001 mm/y under test conditions of 25 °C, 40 °C, and 60 °C, respectively. In contrast, the unalloyed steels exhibited corrosion rates of 0.370 ± 0.033 mm/y, 0.060 ± 0.01 mm/y, and 0.378 ± 0.032 mm/y, respectively. The data indicate that the copper-alloyed materials demonstrate superior resistance to MIC, as confirmed by corrosion morphology, weight loss measurements, and electrochemical data. These findings suggest that copper alloying can significantly enhance the MIC resistance of steel materials, offering a promising direction for future material development.

Effects of the Ultrasonic Surface Rolling Process on the Surface Integrity, Wear Resistance, and Corrosion Resistance of 4Cr5MoSiV1 Tool Steel Before and After Quenching

Effects of the Ultrasonic Surface Rolling Process on the Surface Integrity, Wear Resistance, and Corrosion Resistance of 4Cr5MoSiV1 Tool Steel Before and After Quenching

Structure and properties of composite nanostructured coatings on steel

Abstract In the recent years, the development of nanotechnology has increased the applications of nanoparticles, and the possibility of incorporating them into innovative composite coatings. In this paper, we aim to improve the corrosion resistance of 42CrMo4 and 65G steels by electroless chemical deposition of Ni, reinforced by adding of nanoparticles of nanodiamants (ND), boron (B) or cubic-BN (CBN). Consequently, by this approach we extend the useful-life of these mechanical parts, making them suitable for aerospace and automotive industry.

Corrosion Resistance of Cr10Mo1 Alloy Corrosion-Resistant Steel in Seawater–Sea Sand Concrete Pore Solution

Corrosion Resistance of Cr10Mo1 Alloy Corrosion-Resistant Steel in Seawater–Sea Sand Concrete Pore Solution

Formation mechanism and properties of superhydrophobic surface of ship plate steel

Superhydrophobic surface of ship plate steel was constructed by chemical etching and low surface energy modification. Formation mechanism and properties of the superhydrophobic surface were investigated through SEM, FT-IR, electrochemical analysis and anti-icing evaluation. Corrosion and dissolution of ferrite creates a high-roughness surface with a micro-nano composite structure, and a monomolecular layer of low surface energy material covers steel surface through chelation coordination of stearic acid and Fe, which endows ship plate steel surface with superhydrophobicity. Compared with bare steel, the superhydrophobic surface shows high corrosion resistance, while 75.2% of surface icing is prevented, achieving the purpose of anti-water, anti-icing and corrosion resistance of ship plate steel. In addtion, the simple and cost-effective preparation technique is conducive to large-scale industrial applications in the future.

Effect of aging on the structure and mechanical properties of austenite stainless steel N50 alloyed with nitrogen, niobium and vanadium

In this study, the austenitic, corrosion-resistant N50 steel alloyed with different nitrogen, niobium and vanadium content was investigated. This steel is used in the production of high-strength, cryogenic pipes. The production process for these pipes involves aging at 650 °C–665 °C for 50–100 h. Therefore, steels were examined in their as-delivered state, after aging at 650 °C, 100 h and after solid solution heat treatment. The structure of the steel was analyzed using optical and scanning microscopy, tensile and impact strength tests were conducted at room temperature and at −196 °C. It was found that the total volume fraction of the precipitated phase after aging is more dependent on the total concentration of nitride-forming elements—Nb and V, than on nitrogen. Aging does not affect the basic operational properties at room temperature, but it can significantly affect toughness at −196 °C.

Electrophoretic Deposition of Barium Titanate Nanopowder Coatings for Corrosive Protection of Carbon Steel

Nanomaterials coatings were developed for corrosion protection of carbon steel. Barium titanate (BaTiO3) possesses a distinctive layered structure that can be effectively utilized to enhance the resistance to corrosion in industrial coating systems. Homogeneous Barium titanate films were deposited successfully by electrophoretic deposition (EPD) using an aqueous suspension under altering deposition time. An investigation was conducted using electrochemical measurements to determine the impact of a Barium titanate BaTiO3 coating on the corrosion resistance of carbon steel. Deposited layers characterizations such as adhesion and wettability have been investigated. X-ray Diffraction (XRD), a field emission scanning electron microscope (FE-SEM), and Energy Dispersive Spectroscopy (EDX) confirmed the successful incorporation of the composites in the coating. The corrosion protection properties of the prepared coatings were evaluated using OCP, Tafel, and Cyclic Voltammetry (CV) measurements. The surface morphology of the coatings after corrosion was studied using Field Emission Scanning Electron Microscopy (FESEM). The scanning electron microscope (SEM) analysis of the deposited thin film shows that the film is adhered, dense, and free of voids. This characteristic allows the coated carbon steel to have a high corrosion resistance.

Revealing the impact of inclusion types on pitting corrosion behavior of high-nitrogen stainless bearing steels with different Ce contents: Induction effect of oxides/sulfides and inhibition effect of nitrides

The impact of inclusion types on pitting corrosion behavior of high-nitrogen stainless bearing steels (HNSBSs) with different Ce contents was investigated combining electrochemical tests, microstructure characterization and thermodynamic analysis. The oxide (Al2O3/Ce2O3) and sulfide (MnS/Ce2O2S) inclusions exhibited induction effect on pitting corrosion, while nitride (CeN) inclusion exhibited inhibition effect. Interestingly, CeN inclusion also acted as a protective armor wrapping around Ce2O3 inclusion, alleviating its adverse effect. Moreover, the mechanism of inclusion evolution with Ce content was clarified, and the optimum Ce content in HNSBS was obtained (0.020 wt%). This work provides theoretical guidance for improving corrosion resistance of high-nitrogen steels.

Initial corrosion behavior of 10CrNi3MoV steel and Q235 steel in marine atmosphere

Exploring the corrosion behavior of materials in a marine atmosphere and studying their corrosion resistance mechanisms can provide a basis for developing new weathering steels. This paper primarily introduces the initial corrosion behavior and corrosion resistance mechanism of 10CrNi3MoV steel in a marine atmosphere and explores the effects of Ni on the corrosion resistance. The corrosion resistance of 10CrNi3MoV steel and Q235 steel was compared using the weight loss method. The results show that the corrosion rate of 10CrNi3MoV steel was approximately half that of Q235 steel. The rust layer morphology and elemental distribution of 10CrNi3MoV steel were observed via scanning electron microscopy and energy-dispersive X-ray spectroscopy. The composition of the rust layer was analyzed using X-ray diffraction and X-ray photoelectron spectroscopy, and the protective effect of the rust layer was further tested using an electrochemical test. The reason why Fe2NiO4 is beneficial for improving the corrosion resistance of the rust layer was explained using the Vienna Ab initio Simulation Package. The results reveal that the morphology, composition, element distribution, and electrochemical properties of 10CrNi3MoV steel were considerably stronger than those of Q235 steel because of the formation of Fe2NiO4 in the rust layer. Fe2NiO4 refines the rust layer particles and promotes the transformation of corrosion products to α-FeOOH. In addition, it imparts ion selectivity to the rust layer, effectively blocking the invasion of Cl−.

Investigations on corrosion resistance of steel coated with chromium-free ZTM conversion coating

Chromium–free conversion coatings based on Zr/Ti/Mo (ZTM) compounds via chemical conversion technology were investigated to improve the corrosion performance of SPCC-JISG 31 steels. A preliminary study was carried out to evaluate the influences of critical parameters, including the concentrations of active species Zr, Ti and Mo, and the conversion bath's pH, on the protective efficiency using a Statistical design of experiments (DoE) methodology. Passivation layer with compositional Mo, Ti and Zr elements has been employed on the steels by dipping in mixed solutions containing 17 g/l Na2MoO4, 1 g/l K2TiF6 and 7 g/l K2ZrF6 under pH = 5. The morphology and elemental analysis of Zr/Ti/Mo on surface of the steels was studied by the employment of scanning electron microscopy with energy dispersive spectroscopy (SEM/EDS). Pull-off adhesion test was performed, indicating that the ZTM coatings enabled to increase the adhesion strength (6.0 MPa) of mild steel to the organic coating than that of traditional phosphate (ZrP) coating. The results of electrochemical impedance spectroscopy and the salt spray test (529 h) evidenced the higher corrosion resistance of the Zr/Ti/Mo coating compared with theconventional phosphate coating.