Corrosion Resistance Of Steel Research Articles

Effect of nitrogen pressure on the microstructure, conductivity, and corrosion resistance of ZrN-coated stainless steel as bipolar plate for proton exchange membrane fuel cell

Zirconium nitride (ZrN) coatings were deposited on the stainless steel using multi-arc ion plating under varying nitrogen partial pressures (PN) ranging from 0.5 to 3.5 Pa. The effect of phase composition, microstructure, and surface morphology on the corrosion resistance and conductivity of the ZrN-coated stainless steel in a simulated proton exchange membrane fuel cell (PEMFC) cathode environment was systematically explored. XRD and TEM revealed that the columnar-structured ZrN coating mainly comprised the fcc-ZrN phase. The Zr3N4 phase was discovered near the substrate during coatings prepared at low nitrogen partial pressures. Surface defects were reduced at nitrogen partial pressures exceeding 2.5 Pa. The ZrN coating exhibited enhanced corrosion resistance and conductivity (ZrN-3.5, Ecorr = 0.307 V, Icorr = 2.085 × 10−7 A/cm2, Rct = 1.125 × 105 Ω·cm2) compared to bare stainless steel in the simulated PEMFC cathode environment. The presence of surface defects influenced the corrosion resistance, while differences in conductivity were related to the phase composition and microstructure of the coating. Thus, the findings indicate that ZrN coatings prepared under optimal deposition conditions can have potential applications in PEMFC bipolar plates.

Effect of tempering process on the mechanical properties and corrosion resistance of E690 marine steel

Abstract This study investigated the effect of the tempering process on the microstructure, mechanical properties, and corrosion resistance of E690 marine steel, aiming to replicate actual production conditions and reduce costs. Various techniques, including metallurgical microscopy, scanning electron microscopy, transmission electron microscopy, electron backscatter diffraction, impact experiments, tensile tests, and electrochemical corrosion tests, were employed to evaluate the material’s properties and performance. The results indicated that as the tempering temperature increased, the tempering degree in the tempered martensite structure improved, martensite strips coarsened, the size of precipitated carbides increased, and the proportion of large-angle grain boundaries decreased. Consequently, the tensile and yield strengths initially increased and then decreased, while the impact toughness and elongation gradually improved. At a tempering temperature of 600 °C, the steel exhibited the best overall mechanical properties, with a tensile strength of 729 MPa, a yield strength of 649 MPa, and an elongation of 18%. Furthermore, at a tempering temperature of 550 °C, the test steel showed optimal corrosion resistance, with a corrosion rate of 0.03233 mm/y and an open-circuit potential of -0.36 V.

ABOUT THE POSSIBILITY OF USING CORROSION-RESISTANT STEEL 08X22H6T IN THE DESIGNS OF MAGNETIC COUPLINGS AND MAGNETIC SYSTEMS

The influence of the brand of the material from which the magnetic conductors are made on the power characteristics of the magnetic system and magnetic coupling with highly coercive permanent magnets Nd–Fe–B with a residual magnetic induction of 1.1 T is considered. The material of the magnetic conductors is steel 15 or corrosion-resistant steel 08Х22H6T. On average, in the range of air gaps between sections of the magnetic system from 4 to 10 mm, the decrease in the specific shear force with magnetic conductors made of corrosion-resistant steel 08Х22Н6T, relative to magnetic conductors made of steel 15 is 18.15 %.

The corrosion properties of ferritic stainless steel with varying Cr and Mo contents in the early stages of a simulated proton exchange membrane fuel cell environment investigated using experimental and joint calculation method HKD

The initial corrosion resistance of ferritic stainless steels with various Cr and Mo levels in simulated fuel cell environments is evaluated using the HKD calculation method and electrochemical tests. HKD utilizes high-throughput DFT, KMC, and AIMD statistical coverage calculations to study passivation film development and ion/molecule adsorption behaviors, like O2-, F-, H2O, and OH-. Super-high Cr-containing Mo steel shows reliable corrosion resistance due to their stable structure and effective passivation film integrity at various F- concentrations and pH values. Furthermore, the impact of F- competes with O2-, influencing film formation as pH lowers and concentration rises.

Nitrogen-rich skeleton reassembled ECOFs as energetic materials with low sensitivities and good corrosion resistance

Corrosion between energetic materials and metal containers can accelerate material aging and failure, significantly affecting the safety, reliability, and lifespan of ammunition systems. To address this challenge, we propose the construction of energetic covalent organic frameworks (ECOFs) as a promising solution. We introduce a straightforward method for synthesizing nitrogen-rich ECOFs. The synthesized ECOFs were characterized through powder X-ray diffraction (PXRD), solid-state nuclear magnetic resonance (ssNMR), and Fourier-transform infrared spectroscopy (FTIR). These frameworks exhibit remarkable thermal stability, with decomposition temperatures above 285 °C. Notably, they display low sensitivity to non-explosive stimuli, as evidenced by impact sensitivity over 60 J and friction sensitivity over 360 N. The anti-rust properties of the ECOFs were further evaluated using Tafel curve analysis, highlighting their exceptional resistance to metal corrosion. Particularly, ECOF-3, synthesized from triaminoguanidine nitrate and 5-nitro-1,3-benzenedicarboxaldehyde, stands out for its superior steel corrosion resistance. These ECOFs have potential applications as high-energy, anti-corrosion coatings materials.

Sodium humate as green corrosion inhibition for enhanced corrosion resistance of EH40 ship plate steel

A new green corrosion inhibitor was extracted and prepared from available and inexpensive natural humic plant humus for the corrosion inhibition of EH40 steel in a 15 % HCl medium. The corrosion inhibition properties of SH were evaluated using weight loss, cyclic voltammetry, potentiodynamic polarization and electrochemical impedance spectroscopy. The morphology of EH40 steel was characterized using scanning electron microscopy, atomic force spectroscopy and x-ray photoelectron spectroscopy. It was found that, the optimum concentration of sodium humate was 1.0 gL−1 with an inhibition efficiency of above 95 %. The corresponding corrosion inhibition mechanism was proposed, in which the corrosion inhibitor formed a film on the surface of EH40 steel as a result of the synergistic adsorption effect of chemistry and physics, improving its corrosion retention in the strong acid medium.

Enhancing corrosion resistance of 316L stainless steel through electrochemical deposition of polyaniline coatings in acidic environments

Stainless steel is widely used because of its excellent corrosion resistance in typical environments. However, it is susceptible to corrosion in acidic media, therefore, to address this issue, the electrochemical deposition of polyaniline coatings on 316L stainless steel was investigated using cyclic voltammetry at different potential windows and scan rates. The successful polymerization and surface morphology were analyzed using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), respectively. Moreover, thermal stability of the PANI coating was assessed through thermo gravimetric analysis while the corrosion behavior of bare and coated steels immersed in 1M H2SO4 was studied using electrochemical impedance spectroscopy (EIS). Based on the Nyquist plots obtained from the EIS revealed that the corrosion resistance of the PANI coating improved significantly with a decrease in scan rate and by limiting the upper potential, especially during longer exposure times up to 72 h. Results suggest that controlling the deposition parameters and optimizing the electrochemical conditions can lead to even greater improvements in the corrosion resistance of the stainless steel. These findings offer valuable insights for researchers and engineers in the field of materials science and corrosion protection, enabling them to develop more precise and efficient strategies for enhancing the durability and performance of stainless steel in acidic environments.

Research on the Macro-Cell Corrosion Behavior of Alloyed Corrosion-Resistant Steel for a Transmission Line Steel Structure under a Chloride Corrosion Environment

“The article investigates the macro-cell corrosion behavior and corrosion resistance when the alloyed steel and the carbon steel are used together because the traditional carbon steel is difficult to meet the corrosion resistance and durability of the steel structure of the transmission line in the marine environment.” In this paper, a new type of Cr-alloyed corrosion-resistant steel (00Cr10MoV) is used to partially replace carbon structural steel in order to meet the actual needs of corrosion resistance and service life improvement of steel structures for offshore transmission lines. It is important to systematically study the macro-cell corrosion behavior of combinations of the same type of steel and dissimilar steel, induced by the chloride concentration difference in simulated concrete solutions, and employ electrochemical testing methods to scientifically evaluate the corrosion resistance of steel after macro-cell corrosion. The aim is to study and evaluate the macro-cell corrosion behavior of alloyed corrosion-resistant steel and to lay a foundation for its combined use with carbon steel in a chloride corrosion environment to improve the overall corrosion resistance and service life. Under the same concentration difference, the macro-cell corrosion of the alloyed steel combination is milder compared with the carbon steel combination. The corrosion current of the alloyed steel combination at 29 times the concentration difference is only 1/10 of the carbon steel combination. Moreover, at 29 times the concentration difference, the macro-cell corrosion potential of dissimilar steel is only 1/6 of the combined potential of carbon steel combination under the same concentration difference, and the corrosion current is only 1/10 of that of the carbon steel combination.

Газоциклические процессы химико-термической обработки: регулирование строения азотированного слоя в железе и сталях

The relevance of the research is determined by the needs of mechanical engineering in the development of inexpensive and effective technologies for surface hardening of steel products, which include gas nitride hardening. The aim of the work is to study the effect of nitride hardening in the gas-cyclic regime on the kinetics of growth of diffuse layers and their phase composition in case of iron and steel: ChWMn tool steel and corrosion-resistant maraging steel 03Ch11Ni10Mo2Ti (WSTST17). In addition to isothermal processes (at 520 ℃ and 620 ℃), processes with temperature changes at active and passive stages (thermal cycling 520 ℃ / 620 ℃) have been studied. It has been found that gas and thermal cycling significantly increases the thickness of the diffusion layer in iron compared to traditional nitride hardening in ammonia, and this is mainly due to the growth of the internal nitriding zone. Processes with multitime repeat short half-cycles, which end in an active saturation stage in ammonia and contribute to the formation of a developed nitride zone. The formation of surface layers in iron without an ε -phase occurs in two-stage processes with a final passive stage. It is shown that thermo-gas cyclic processes provide a multiple increase in the thickness of the internal nitriding zone in ChWMn steel. Processes with a duration of half cycles of 1 and 1,5 hours with the final stage of denitration contribute to the predominance of the γ' phase in the carbonitride zone, which explains the increase in wear resistance. A thermal gascyclic process of 530 ℃ / 580 ℃ in a pulsating ammonia-air mixture with a final passive stage is used to form a junction zone based on the γ'- phase in steel 03Ch11Ni10Mo2Ti (WSTST17).

Electrochemical Characteristics and Corrosion Mechanisms of High-Strength Corrosion-Resistant Steel Reinforcement under Simulated Service Conditions

Long-term steel reinforcement corrosion greatly impacts reinforced concrete structures, particularly in marine and coastal settings. Concrete failure leads to human casualties, requiring extensive demolition and maintenance, which represents an inefficient use of energy and resources. This study utilizes microscopic observation, atomic force microscopy (SKPM), electrochemical experiments, and XPS analysis to investigate the corrosion behavior of 500CE and 500E under identical conditions. We compared 500E with 500CE, supplemented with 0.94% Cr, 0.46% Mo, 0.37% Ni, and 0.51% Cu through alloying element regulation to obtain a finer ferrite grain and lower pearlitic content. The results indicate that 500CE maintains a stable potential, whereas 500E exhibits larger grain sizes and significant surface potential fluctuations, which may predispose it to corrosion. In addition, despite its more uniform microstructure and stable electrochemical activity, 500E shows inferior corrosion resistance under prolonged exposure. The electrochemical corrosion rate of 500CE in both the pristine and passivated states and for various passivation durations is slower than that of 500E, indicating superior corrosion performance. Notably, there is a significant increase in the corrosion rate of 500E after 144 h of exposure. This study provides valuable insights into the chloride corrosion phenomena of low-alloy corrosion-resistant steel reinforcement in service, potentially enhancing the longevity of reinforced concrete structures.

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.