Corrosion Resistance Of Steel Research Articles

Examination of the main chemical components of essential oil of Syzygium aromaticum as a corrosion inhibitor on the mild steel in 0.5 M HCl medium

The study delves into the versatile applications of essential oils, natural aromatic compounds derived from plants through hydro-distillation or cold extraction, across industries such as cosmetics, fragrances, food processing, traditional medicine, and agriculture. Notably, these plant-derived compounds have gained prominence as corrosion inhibitors for metals and alloys in acidic environments. The research focuses on evaluating the inhibitory capacity of Suzygium aromaticuim on regular steel submerged in an acidic medium, employing various concentrations of essential oil (1.5 g/L to 6 g/L). The inhibitory effectiveness was evaluated using electrochemical techniques, including potentiodynamic polarization curves and electrochemical impedance spectroscopy. Electrochemical measurements and optical microscope analyses were used to examine the effect of cloves' essential oils on the corrosion resistance of mild steel in a 0.5 M HCl media. NMR and IR spectroscopy were used to learn about the two isolated chemicals (eugenol and β-caryophyllene). The corrosion-inhibiting properties of β-caryophyllene at 2 g/L in an acidic media were studied. Density functional theory (DFT) computations and molecular dynamics simulations were used to isolate the essential oil component of cloves responsible for the corrosion inhibition of mild steel. Inhibition effectiveness peaked at 94 % at 4 g/L, leading the researchers to infer that the natural substance is a mixed-type inhibitor. Optical microscope analysis confirmed the protection offered at the optimum concentration, while β-caryophyllene demonstrated noteworthy inhibitor efficiency, especially when compared to Eugenol. DFT analysis further supported the corrosion inhibition potential of β-caryophyllene in aggressive solutions.

Tensile Effect on Sensitization and Corrosion Resistance of Stainless Steels

The purpose of this research is to investigate cold work effect on corrosion behavior of stainless steels of type AISI 304, AISI 316L and AISI 2101. The specimen were processed through cold work simulated by the tensile test at various percentages elongation and then tempered at 600°C for different time intervals. Two electrochemical techniques and hardness test were utilized in this investigation. The first technique was the double loop electrochemical potentiokinetic reactivation (DL-EPR) that yields the values of degrees of sensitization (DOS). The second one was the cyclic potentiodynamic polarization (CPP) to study the ability of the metals to build or repair the damaged films under localized corrosion. The DOS values from the DL-EPR tests of the samples under the same heating conditions suggested that specimens drawn at higher percentage elongation tend to have more chromium depleted areas. Also, the test specimens with more exposure time to heat were more prone to chromium deficiencies. As for the ability of the metal to create or repair damaged film after corrosion has occurred, it was found that AISI 316L had hihger corrosion resistance than AISI 304. However, AISI 2101 stainless steel had highest corrosion resistance. In this study, it was also found that AISI 2101 did not exhibit pitting corrosion, but the crevice corrosion. This could be due the fact that AISI 2101 which is a duplex stainless steel has high corrosion resistance and could trigger the crevice corrosion take place before the pitting initiation.

Enhancing low-speed WEDM machining capabilities on Nitronic-50 with a constant frequency ultrasonic hybrid method

Nitronic-50 stainless steel is a high-strength and corrosion-resistant austenitic premium steel. It requires improved surface characteristics due to its wide use in various applications like fasteners, marine hardware, hydroelectric-power turbines, pressure vessels, etc. This work focuses on machining hard-to-machine Nitronic-50 steel is unconventionally machined using constant frequency ultrasonic-aided low-speed wire electrical discharge machining (USV-LS-WEDM) to enhance its machined surface integrity. This method achieves effective results when cutting high-strength materials with intricate shapes. Material removal rate (MRR) and surface roughness (Ra) were measured by considering inputs such as servo voltage (SV), pulse off time ( Toff), pulse on time ( Ton) and current (I) with an ultrasonic-vibration range of 20,000 Hz. The appropriate selection and usage of LS-WEDM parameters is a challenging process and is done with parametric analysis. The MRR of Nitronic-50 was enhanced with an increase in Ton and I along with a reduction in Toff and SV. Surface roughness (Ra) decreased with a gradual reduction in Ton, I, and an increase in SV. The USV-WEDM was compared with a stand-alone WEDM indicating that the MRR for USV-WEDM was improved by 12% and the Ra was decreased by 9% due to effective distribution of spark discharges, which increased material erosion and redistribution of molten metal characteristics. Machining quality for hard-to-machine Nitronic-50 steel was certainly enhanced via hybrid ultrasonic vibration with the existing LS-WEDM.

Improving the corrosion resistance of Inconel 52M laser-cladded steel

Inconel 52M (In52M) laser-cladded steel was analyzed to study the effect of process parameters on the wire deposition mode and the melt pool geometry, which was shown to have a significant effect on the microstructural morphology and the resulting corrosion resistance of the clad. The processing parameters controlled the size and fluid flow in the molten clad pool during clad deposition. The results showed that by decreasing the size of the melt pool during cladding, the growth of coarse Al- and Ti-oxides could be substantially restricted. The presence of these coarse oxides was identified as one of the main causes of poor corrosion resistance in In52M cladded steel. The results showed that by limiting the formation and growth of these oxides, the corrosion resistance of the clads could be drastically improved. The results also showed that the corrosion resistance of In52M clads was not significantly affected by the rate of dilution of the Fe substrate into the clad, which is generally thought to be the most significant factor affecting corrosion performance. This study definitively showed that the corrosion resistance of In52M cladded steel can be considerably improved by adjusting the processing parameters to ensure a relatively small melt pool size during clad deposition, which limits the formation of harmful coarse oxides close to the outer surface of the clad, regardless of the rate of dilution.

Experimental and computational study of L-Glutathione reduced as a green corrosion inhibitor for mild steel in alkaline environment

L-Glutathione reduced (GSH) is a small molecule peptide found in large quantities in living organisms, particularly in animal liver cells. Its unique structure gives it great potential to act as an environmentally friendly and efficient corrosion inhibitor. The inhibition properties of GSH for mild steel in simulated concrete pore solutions (SCPS) containing chlorine was investigated by electrochemical tests and SEM-EDS surface analysis. According to the experimental results, GSH mainly blocked the cathodic corrosion reaction and has a corrosion inhibition efficiency of up to 92.3% at room temperature, enhancing the corrosion resistance of mild steel. The isothermal adsorption results indicate that the adsorption behavior of GSH on the surface follows the Langmuir isothermal adsorption model. Both quantum chemical calculations (QC) and molecular dynamics simulations (MD) show that GSH can be effectively adsorbed onto mild steel substrates, thus protecting the surface from erosion. Finally, the results of the above experiments and theoretical calculations are combined to elucidate the inhibitive mechanism: GSH molecules binds to the iron surface via the sulfur, nitrogen and oxygen atoms in the molecule, thus adsorbing to the iron surface in a tiled manner and forming a protective film to prevent the corrosive material from contacting the iron surface.

Investigating molybdenum’s sulphur scavenging ability for MoS2 formation in preventing pitting corrosion of stainless steels

The addition of Mo enhances pitting corrosion resistance in 304L stainless steel. However, there is no consensus on the underlying mechanism. One possible explanation is that molybdenum converts sulfide to stable MoS2. This study investigates the effect of MoS2 inclusion on the corrosion of 304L stainless steel by introducing both MnS and MoS2 using spark plasma sintering. The reduction of MoS2 to Mo is observed during the sintering process, contradicting the assumption that the sulfide inclusions can be stabilised by forming MoS2. Therefore, MoS2 formation cannot explain the improved corrosion resistance of 304L stainless steel with the addition of Mo.

The effect of build orientation on tensile properties and corrosion resistance of 316L stainless steel fabricated by laser powder bed fusion

The effects of build orientation on tensile property and corrosion behavior of laser powder bed fusion 316L stainless steel were investigated. The laser powder bed fusion 316L stainless steel in normal direction exhibited lower tensile strength and elongation than one in build direction. In view of the fact that there was no obvious martensitic transformation in the two samples, high density dislocation and more low-angle grain boundaries in laser powder bed fusion 316L stainless steel in build direction both enhanced tensile yield and tensile strength. More deformed twins in the sample in build direction induced better plasticity. In addition, laser powder bed fusion 316L stainless steel in build direction exhibited better corrosion resistance than one in normal direction in borate buffer and sodium chloride solutions. This was attributed to the larger grain and more densely packed crystallographic faces in build direction for laser powder bed fusion 316L stainless steel.

Dynamic Recrystallization Behavior of Q370qE Bridge Steel

Bridge steel has been widely used in recent years for its excellent performance. Understanding the high-temperature Dynamic Recrystallization (DRX) behavior of high-performance bridge steel plays an important role in guiding the thermomechanical processing process. In the present study, the hot deformation behavior of Q370qE bridge steel was investigated by hot compression tests conducted on a Gleeble 3800-GTC thermal-mechanical physical simulation system at temperatures ranging from 900 ℃ to 1100 ℃ and strain rates ranging from 0.01 s−1 to 10 s−1. The obtained results were used to plot the true stress-strain and work-hardening rate curves of the experimental steel, with the latter curves used to determine the critical strains for the initiation of DRX. The Zener-Hollomon equation was subsequently applied to establish the correspondence between temperature and strain rate during the high-temperature plastic deformation of bridge steel. In terms of the DRX volume fraction solution, a new method for establishing DRX volume fraction was proposed based on two theoretical models. The good weathering and corrosion resistance of bridge steel lead to difficulties in microstructure etching. To solve this, the MTEX technology was used to further develop EBSD data to characterize the original microstructure of Q370qE bridge steel. This paper lays the theoretical foundation for studying the DRX behavior of Q370qE bridge steel.

A novel dual-functional pretreatment layer for carbon steel in chloride-contaminated concrete pore solutions

The improvement of the anti-corrosion performance of reinforcing steel is crucial for extending the service life of reinforced concrete (RC) structures. This study proposes a novel approach to enhance the corrosion resistance of carbon steel in concrete exposed to aggressive environments. By applying a phytic acid (PA) composite pretreatment layer with polyvinyl alcohol (PVA) and potassium titanate whisker (PTW), a protective film containing corrosion inhibitors was formed, resulting in improved resistance to chloride attack. The PA-PVA grafting solutions effectively fixed PTW onto the steel surface due to their strong chelating ability, while the PTW skeleton structure not only increased the pretreatment layer thickness but also provided space for loading corrosion inhibitors. The fundamental characteristics of the pretreatment layer were evaluated using SEM-EDS, XRD, ATR-FTIR and XPS. Meanwhile, electrochemical results showed that carbon steel exhibited improved corrosion resistance to chloride attack with high inhibition efficiency owing to the formation of a bilayer protective film. As a newly developed pretreatment layer, it is expected that the PA composite pretreatment layer will confer multifunctional properties to RC structures.

Design of P110 steel wire beam electrode for high temperature and pressure environment and application for revealing corrosion mechanism

PurposeThe purpose of this work is to design the wire beam electrode (WBE) of P110 steel and study its corrosion behavior and mechanism under high temperature and pressure.Design/methodology/approachPackaging materials of the new type P110 steel WBE and high pressure stable WBE structure were designed. A metallurgical microscope (XJP-3C) and scanning electron microscopy (EV0 MA15 Zeiss) with an energy dispersive spectrometer were used to analyze the microstructure and composition of the P110 steel. The electrochemical workstation (CS310, CorrTest Instrument Co., Ltd) with a WBE potential and current scanner was used to analyze the corrosion mechanism of P110 steel.FindingsAccording to the analysis of Nyquist plots at different temperatures, the corrosion resistance of P110 steel decreases with the increase of temperature under atmospheric pressure. In addition, Rp of P110 steel under high pressure is maintained in the range of 200 ∼ 375 Ωcm2, while that under atmospheric pressure is maintained in the range of 20 ∼ 160 Ωcm2, indicating that the corrosion products on P110 steel under high pressure is denser, which improves the corrosion resistance of P110 steel to a certain extent.Originality/valueThe WBE applied in high temperature and pressure environment is in blank. This work designed and prepared a WBE of P110 steel for high temperature and pressure environment, and the corrosion mechanism of P110 steel was revealed by using the designed WBE.

Synergistic impact of the functionalized graphene oxide (fGO) nano-sheets and Mn2+-doped zinc phosphate conversion film on the polyester coating corrosion protection properties

Corrosion protection is crucial for steel, and one effective method is applying organic coatings as a barrier between the steel and corrosive surroundings. However, defects and poor adhesion can compromise their effectiveness. Phosphating-based treatment is a widely used method to enhance corrosion resistance, but traditional processes are time-consuming. Recent advancements include low-temperature phosphating and nanoparticle-based accelerators. Graphene oxide (GO) nanoparticles have gained attention for improving corrosion resistance. The purpose of this study is to investigate the corrosion resistance of zinc phosphate conversion coatings on steel with functionalized graphene oxide (fGO) and Mn2+ cations, as well as polyester coatings. FT-IR, Raman, XRD, XPS, and FE-SEM analyses were conducted for thin film characterization. Furthermore, results show improved corrosion resistance for coated samples, especially with fGO and Mn2+. EIS, polarization tests, and salt spray tests confirm the enhanced protection. Evaluation of the intact and scratched coatings further demonstrates the barrier properties and self-healing ability. Overall, the study highlights the potential of incorporating nanomaterials and phosphating treatments to enhance the corrosion resistance of steel.

Influence of metal structure on the fatigue strength of products obtained by additive growth

The results of experimental studies of the fatigue strength of specimens obtained by 3D printing from various metal wires during additive growth using the WAAM technology are presented. It is established that the fatigue strength of specimens made of 08Х18Н9 corrosion-resistant steel is higher than that of specimens made of low-carbon 08Г2С steel and АМг5 aluminum alloy. It is shown that the fatigue strength of 08Х18Н9 steel is related with its high plasticity. Ways of increasing the plasticity of metals are proposed. Keywords: 3D printing, specimens, wire, metals, fatigue strength, plasticity, fracture. uru.40@mail.ru

Influence of increased voltage on the nitriding zone during plasma nitriding

AbstractPlasma nitriding is an established process for increasing the corrosion and wear resistance of steel. However, the possibilities of modern developments in the field of high‐voltage plasma power supplies have been hardly investigated. For example, modern plasma generators allow improved arc management, which enable plasma nitriding at higher voltages.In the present work, the influence of increased voltage (up to 800 V) on the nitriding of a ferritic steel X38CrMoV5‐1 was investigated. It was found that the thickness of the compound layer increases with increasing voltage. Especially at short process times the increased voltage leads to increased growth. An increase in the nitriding depth was also observed.Furthermore, the increased voltage has an effect on the composition of the compound layer too. A moderate increase in ϵ‐nitride in the compound layer was observed.One explanation for the observed behavior is the over proportional increase in power with increasing voltage, indicating an increased ionization rate of the plasma. Due to this, more diffusible species would be available for nitriding.The presented results could be used to reduce process times, particularly where the formation of a compound layer is the aim of the process. An example of such a process is oxy‐nitriding.

Učinkovitost armature premazane ekstraktom kore nara u betonu pri zaštiti od korozije

This paper aimed to develop an affordable, eco-friendly, and accessible natural inhibitor derived from the peel of the pomegranate fruit. An extract was prepared from the pomegranate peel and utilised as a corrosion-resistant coating known as pomegranate peel extract (PPE) applied to the steel rebar. The corrosion resistance of the PPE-coated steel was evaluated using accelerated carbonation, impressed voltage, half-cell potential, weight loss, and accelerated corrosion tests. The carbonation test revealed that the uncoated steel rebar displayed patches, indicating carbonation, whereas the PPE-coated rebar was not affected, demonstrating an uncarbonated zone. Moreover, the half-cell potential test clearly indicated that the PPE-coated steel rod exhibited a moderate risk of corrosion with a potential of -247 mV. Particularly, the weight loss of the uncoated conventional steel was 40 % greater than that experienced by the PPE-coated rod. In the accelerated corrosion test, the PPE-coated rods took longer to develop initial cracks in the concrete, with durations of 182, 206, and 230 h for samples 1, 2, and 3, respectively, which were comparatively higher than those of conventional concrete. Thus, the test results of the PPE-coated steel were compared with those of the uncoated conventional steel, and the performance of the PPE-coated rod in terms of corrosion resistance was evaluated.

HEAT-RESISTANT MULTIFUNCTIONAL COATING FOR THE PROTECTION OF CORROSION-RESISTANT STEEL PARTS

A new heat-resistant multifunctional glass-based coating has been developed in the BaO–B2O3–SiO2 system, which protects parts made of corrosion-resistant steels from high-temperature gas corrosion at temperatures up to 900 ?C. The developed heat-resistant multifunctional coating has increased resistance to high temperatures, high dielectric properties, and therefore is multifunctional. A high level of properties is provided by a composition based on refractory glass and the addition of a bonding activator.

Corrosion Behaviors’ Investigation of Carbide Coatings Developed for Sulphuric Acid Recovery Systems

In this study, corrosion resistance of cobalt and nickel, which are known to have high corrosion resistance, reinforced tungsten carbide coatings applied to low carbon stainless steel material surfaces to reduce corrosion-induced losses in sulphuric acid recovery systems were investigated. During the recovery of sulphuric acid, aggressive sulphur systems in the baths cause the metal surface to dissolve and therefore a high amount of material loss occurs. In order to minimize corrosion induced material loss, 316 L stainless steel surfaces were coated with an interlayer of 95% nickel and 5% aluminium alloy, and then tungsten carbide coatings were synthesized on the surfaces of substrate materials reinforced with 13% cobalt and 13% nickel, respectively by thermal spraying method to further reduce the corrosion rate. Characterization of the produced coatings were carried out by X-ray diffraction (XRD), scanning electron microscope (SEM), optical microscope, image analyzer, and surface roughness device. The standard potentiodynamic polarization characteristics of the coatings for 1M H2SO4 solution at room temperature were investigated with a potentiostat/galvanostat device. As the obtained results, nickel reinforced tungsten carbide coatings with nickel aluminium interlayer showed the highest corrosion resistance against sulfuric acid environment with 0,41 mm/year corrosion rate. As a result of the article, the corrosion resistance of 316L stainless steels in sulfuric acid systems was improved by 5.02 and 3.15 times, respectively.

Direct shear setup for studying the THM shear response of the soil-structure interface in the context of energy geostructures

Developing pathways for climate-resilient development involves integrating mitigation and adaptation actions, ensuring sustainable development [1]. A climate-resilient development can be achieved through the inclusion of effective mitigation approaches into development planning, reducing vulnerability, conserving ecosystems, and restoring ecosystems [1]. In this regard, energy geostructures are introduced as an effective mitigating approach, providing renewable energy while limiting the emission of greenhouse gases [2-4]. The operation of the system is closely linked to daily and seasonal cycles, which leads to cyclic temperature and water content fluctuations at the soil and the soil-structure interface [4, 5]. Thus, the study of the shear response of the soil–structure interface subjected to different thermo-hydro-mechanical (THM) conditions is of importance. Testing techniques used to study the THM behaviour of unsaturated soils require advanced laboratory equipment, as well as protocols for correcting measured data due to errors in the test conditions and apparatus calibration. This paper presents the development of a new direct shear setup to measure the non-isothermal shear strength of the partially saturated soils and soil-structure interface. The modified setup, a unique one to the authors' knowledge, enables simultaneous control of temperature, matric suction, and mechanical stress state within the soil specimens. The operational temperature range of energy geostructures (i.e., 5°C to 50) is applied through a thermal plate, developed from corrosion-resistant stainless steel with high thermal conductivity, placed at the base of the soil specimen. Matric suction (i.e., in the range of 0 to 100 kPa) is controlled using the axis-translation technique and measured using a pressure transducer connected to the back of the top cap, incorporating the HAE disk, facilitating the measurement (Figure 1) [2, 4-6]. The direct shear setup is modified to accurately measure the shear strength and deformation characteristics of soil samples under controlled laboratory conditions. The design of the device is based on previous direct shear devices but includes several improvements to enhance its accuracy and ease of use [4, 5]. The device has been tested to measure the shear response of both soils and soil-structure interfaces, and the results were compared to those obtained using conventional direct shear devices [2, 4, 7-10]. The results indicate that the new device is accurate and reliable and represents a significant advancement in the field of soil testing.
 In this study, the interface is formed by kaolin clay, a temperature-sensitive clay, and concrete, a structural material widely used for energy geostructures [4, 11]. The soil samples were prepared by static compaction at 30% initial water content () and an initial void ratio () of 1.2. Initially, all samples were inundated with distilled water at room temperature (24°C) [4, 12], followed by sequential hydraulic (i.e., matric suction, = 0 or 70 kPa), mechanical (i.e., net normal load, =100 or 300 kPa), and thermal (i.e., temperature, =24°C or 45°C) loading of the interface. The shearing was initiated after ensuring equilibrium criteria were met. It was necessary to limit the shearing rate to 0.005mm/min and the thermal loading rate to 3°C/hr to maintain the drained condition [4, 13]. Additionally, the vertical displacements associated with hydraulic load were subjected to an equilibrium criterion of 0.025%/day strain rate [14]. As presented in Table 1, the results revealed that the apparent interface friction angle was not significantly affected by matric suction at varying temperatures, but a slight decrease has been observed upon heating at all matric suctions. The apparent adhesion increased in response to temperature increase/decrease, with a decreasing rate as suction increased, while the interface desaturation led to higher apparent adhesion at all temperatures, corresponding to peak and residual values. In interfaces subjected to identical normal stress and temperature but different matric suction values, the shear stress-shear displacement curves showed greater peak stress with increasing matric suction. Furthermore, despite the same net normal stress and matric suction, higher temperatures resulted in slightly lower peak shear stress and less contractive volume change behaviour at the interface. Non-isothermal volumetric behaviour and soil dilatancy play a significant role in governing the THM shear response of the interface [15].

The Blue Tansy Essential Oil–Petra/Osiris/Molinspiration (POM) Analyses and Prediction of Its Corrosion Inhibition Performance Based on Chemical Composition

Sustainable materials encompass a diverse range of substances used in both consumer and industrial domains. These materials are sourced in quantities that safeguard non-renewable resources and environmental equilibrium, with a focus on bio-based alternatives derived from plants. This study investigates the corrosion inhibition potential of two distinct Blue Tansy essential oils (BTES 1 and BTES 2) with varying chemical compositions. Corrosion resistance for mild steel in 1 M HCl environment was assessed using weight loss and Potentiodynamic polarization techniques. The evaluation of BTES 1 and BTES 2 revealed compelling insights. Notably, their inhibition efficiency exhibited an intriguing, damped oscillation pattern with fluctuating concentrations. Remarkably, at 0.5 g/L concentration, BTES 1 achieved an impressive 80% inhibition, while BTES 2 demonstrated a substantial 70% inhibition at 2.5 g/L. This behavior stems from intricate interactions among active compounds, leading to protective film formation and competitive adsorption effects. Importantly, congruence between weight loss measurements and potentiodynamic polarization curves fortified the reliability of outcomes. The study also confirmed BTES as a mixed-type inhibitor, as indicated by polarization curves. Furthermore, Petra/Osiris/Molinspiration (POM) analyses were conducted to unravel molecule interactions, elucidate toxicity risks, and assess bioactivity scores. This comprehensive exploration sheds light on the interplay between sustainable materials, corrosion inhibition efficacy, and complex molecular dynamics, enhancing our understanding of environmentally conscious corrosion prevention strategies.

Achieving a superior combination of tensile properties and corrosion resistance in AISI420 martensitic stainless steel by low-temperature tempering

The mechanical and electrochemical properties of AISI420 martensitic stainless steels (MSS) tempered at different temperatures (200, 400, and 600 ℃) are systematically investigated. The increased tempering temperature leads to the decreased strength, while the elongation remains relatively stable. Notably, the MSS tempered at 200 ℃ exhibits a superior strength-ductility synergy, featuring a strength of 1.65 GPa, and elongation of 10%. Moreover, increasing tempering temperature reduces the electrochemical properties and pitting corrosion resistance. In the tempered samples, pitting corrosion initiates near the inclusions and carbides, with the Cr-rich carbides and Cr-depleted regions serving as channels that promote the propagation of corrosion.

Influence of post-weld heat treatments on the formation of the sigma phase and the corrosion resistance of S32001 steel

Due to their good resistance to corrosion, duplex stainless steels are often used in more demanding environments. S32001 duplex stainless steels are of recent development, so there is practically no information on how welding processes affect them or which are the best post-weld heat treatments to maintain their corrosion resistance without alterations. This article analyses several welded coupons made with the GMAW process, which have subsequently undergone three different post-weld heat treatments, to evaluate their influence on corrosion resistance. The study has made it possible to determine the influence of heat treatments on the phase balance of ferrite and austenite and on the appearance of the sigma phase. The heat treatments that favour a more balanced phase and, consequently, an improvement in the mechanical properties, could favour the formation of the sigma phase. Therefore, the corrosion resistance would be impaired. The study has made it possible to determine the range of temperatures for the formation of the sigma phase for this duplex (forming mainly between 450 and 850 °C), which differs from the temperature range for duplex stainless steels with other compositions.