Corrosion Resistance Of Steel Research Articles

Welding-induced corrosion and protective measures for clad rebars in neutral chloride environments

Corrosion-resistant steel plays a vital role in marine steel structures. This study developed an SS304/HRB400 stainless-steel-clad rebar for application in a cross-sea bridge in Zhejiang Province. CO2 gas shielded welding was employed in the prefabricated steel structure, with SS304 steel as the welding wire. This study investigated the welding on the corrosion resistance of clad rebars and explored corrosion protection measures for welded joints.The results indicated that refined grains appeared in both stainless steel and carbon steel due to distinct dynamic recrystallization (DRX) during welding. The corrosion resistance, as determined by potentiodynamic polarization curve analysis of the material’s interaction with the solution ranked as follows: clad rebar (polished) > clad rebar welding (CRW) > painting the clad rebar after welding (PCRW) > clad rebar (unpolished) > carbon-steel welding (CSW) > carbon-steel bar > cold spraying zinc after clad rebar welding (ZCRW). However, an accelerated corrosion test with four samples for 600 s with a corrosion current of 0.8 A revealed minimal corrosion damage on zinc-coated surfaces. Hence, welding joints for clad steel structures are considered feasible and must be subject to cold zinc spraying after polishing to enhance their corrosion resistance.

Impacts of temperature and coating pigment ratios on the corrosion rate of ss400 steel

Steel is the primary shipbuilding material; however, it erodes quickly. Adequate protection requires hard, durable, and adhesive coatings. This study examines how aluminium-graphite pigment and heat treatment affect epoxy-coated SS400 steel plate corrosion, adhesion, and coating resilience. This study used a 1:1 and 3:1 pigment ratio with 100°C and 150°C heat treatment. The coating layer was 250 μm thick and comprised 80% epoxy and 20% aluminum-graphite. The maximum adhesion strength, 19.62 MPa, was achieved with an aluminium-graphite pigment ratio of 1:1 and 100°C heat treatment. The top coating resistance was 6.86 Joules under identical conditions. The lowest corrosion rate, 0.047 mmpy, was at a 3:1 aluminum-graphite ratio and 150°C heat treatment. This discovery has significant consequences for shipbuilding steel corrosion resistance.

A novel design method for NiCr coating against supercritical CO2 via the ReaxFF molecular dynamics theoretical analysis and experimental verification

In order to design a NiCr coating with the strongest corrosion resistance, the corrosion behavior of Ni, Ni10Cr and Ni20Cr coatings was studied using molecular dynamics, in which Ni20Cr coating exhibited the best corrosion resistance. The corrosion behavior of Fe9Cr heat-resistant steel with or without Ni20Cr coating in a supercritical CO2 at 650 ℃ and 15 MPa for 1000 h was carried out by corrosion test, which significantly reduced the experimental period and cost. The Ni20Cr coating was intact and uniform after exposure for 1000 h. A dense and continuous Cr-rich oxide film with low growth stress could rapidly formed on the Ni20Cr coating. The Ni20Cr coating could effectively enhance the corrosion and carburization resistance of Fe9Cr heat-resistant steel.

A Novel Amorphous Alloy Coating for Elevating Corrosion Resistance of X70 Pipeline Steel

A Novel Amorphous Alloy Coating for Elevating Corrosion Resistance of X70 Pipeline Steel

Effects of Niobium Addition on the Mechanical Properties and Corrosion Resistance of Microalloyed Steels: A Review

Steel structures are prone to corrosion, a chemical reaction between steel and the atmosphere that gradually weakens the material. Over time, this reaction can significantly reduce the structural integrity and lifespan of steel elements. Without intervention, corrosion can cause structures to fail, leading to financial, environmental, and potential human losses. Enhancing steel’s corrosion resistance is crucial, and one method involves adding niobium (Nb). Niobium microalloyed steels are known for their increased strength, and some research indicates that Nb may also improve corrosion resistance by making the grain structure of the steel finer. However, the complete potential of Nb in corrosion prevention remains underexplored, with significant research gaps across various scales, from microstructural impacts on durability to macroscopic effects on mechanical properties. The research community has utilized numerous experimental approaches to test corrosion resistance under different conditions, but there is a lack of comprehensive studies that aggregate and analyze these findings. This paper seeks to fill that void by reviewing the impact of Nb on the strength and corrosion resistance of structural steels, examining how steel beams’ ultimate capacity degrades over time and identifying key areas where further research is needed to understand Nb’s role in mitigating corrosion.

Effect of Ca-Mg microalloying on corrosion behavior and corrosion resistance of low alloy steel in the marine atmospheric environment

The effect of Ca-Mg microalloying on corrosion behavior of Al deoxidized low alloy steel in the simulated tropical marine atmospheric environments was investigated. The addition improves microstructural characteristics, increasing the corrosion potential by 70±10 mV and decreasing the corrosion rate from 1.66 mm/y to 1.57 mm/y over time. Furthermore, the addition of Ca-Mg has been observed to modify the morphological attributes, population density, dimensional parameters, and electrochemical properties of the prevalent inclusions. This modification is instrumental in shifting the underlying mechanisms that contribute to localized corrosion, which is often precipitated by these inclusions in the steel matrix.

Enhancing the corrosion resistance of high Mo S31254 super austenitic stainless steel using grain boundary engineering

Super austenitic stainless steel (SASSs) with a high Mo content exhibit excellent resistance to intergranular corrosion (IGC), Its mechanical properties mainly depend on solid solution strengthening. Meanwhile, grain boundary engineering (GBE) can simultaneously improve the corrosion resistance and mechanical properties of Mo-rich austenitic stainless steel using the resistance to IGC of Mo. However, recrystallization annealing is extremely difficult due to the sensitive precipitation of Cr-rich and Mo-rich precipitations in SASSs. Therefore, this study explores the effect of large deformation, high temperature, and short-time annealing on the corrosion resistance of SASSs. The results show that a recrystallized organization with an average grain size of 13.3 μm was prepared by 50% cold rolling deformation and 2 min high-temperature short-time annealing at 1150 °C. The highest percentage of Σ3 GBs is about 34%, the percentage of other low-energy GBs is relatively low (only about 6%), and the rest are random high-angle grain boundaries (RHAGBs), which account for about 60%. It can be seen the corrosion resistance of random GBs after GBE treatment is superior to that of solution treatment. Meanwhile, medium-temperature aging improved the resistance to IGC of SASSs, especially after aging at 450 ℃, a small amount of Mo is enriched along the GBs, which promotes the formation of Cr2O3 and Mo-rich oxides in the passivation film and improves the corrosion resistance. The above results provide guidance for improving the corrosion resistance of Mo-rich austenitic stainless steels.

Enhanced corrosion resistance of 9Cr alloy steel via Al alloying in simulated harsh marine atmosphere

The corrosion behaviors of Cr9Ni1 and Cr9Ni1Al in simulated harsh marine atmosphere were studied by dry-wet cyclic test (DWCT). Scanning electron microscopy (SEM), energy disperse spectroscopy (EDS) and electron probe microanalyzer (EPMA) were used to observe the cross-section morphology of rust layer. The composition of corrosion products were analyzed through X-ray diffractometer (XRD) and X-Photoelectron spectroscope (XPS). Electrochemical impedance spectroscopy (EIS) was used to determine the electrochemical properties of rusted samples. The results show that the corrosion rate of both 9Cr alloy steels increases continuously during the initial corrosion process of 576 h, which can be understood from α/γ*>1 of the rust layer and the acidification caused by increased CrO3. Interestingly, the addition of 0.7 % Al reduced the corrosion rate of 9Cr steel by more than 26 %. Al not only generates Al2O3 and Al(OH)3 enriched in the whole rust layer, but also optimizes the rust layer in terms of the Cr distribution, composition of Cr-containing compounds, and α-FeOOH content. Importantly, it is proposed that Al alloying weakens acidification through reducing CrO3 content and partial dissolution of the generated Al(OH)3.

Dissolution and redistribution behavior of Cu-rich phase: Implications for corrosion resistance in Cu-bearing duplex stainless steel in chloride media

In this study, the dissolution and redistribution behaviors of the Cu-rich phases were investigated to determine their effect on the corrosion resistance of Cu-bearing 2205 duplex stainless steels. This investigation revealed the presence of Cu-rich phases with varying precipitation modes in ferrite and austenite, as well as a decrease in corrosion resistance as their size increased. The Cu-rich precipitate was preferentially dissolved compared to the steel matrix. A corrosion-product layer was formed on the surface of the alloy. The Volta potential difference between the Cu-bearing corrosion products and the matrix was lower than that between the Cu-rich phase and the matrix. This reduction in the potential difference enhanced the corrosion/passive film stability and improved the corrosion resistance of the alloy.

Rust Prevention Property of a New Organic Inhibitor under Different Conditions.

The corrosion resistance properties of a new type of environmentally-friendly organic inhibitor containing amino ketone molecules are presented in this paper. To evaluate the prevention effect of the inhibitor on corrosion of reinforcement, the electrochemical characteristics of steels in the simulated concrete pore solution (SPS) were investigated under varied conditions of the relevant parameters, including concentrations of the inhibitor and NaCl, pH value, and temperature. The inhibition efficiency of the material was characterized through electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, and the weight loss of steels. The results reveal a significant improvement in the corrosion resistance of steels with the inhibitor. A maximum resistance value of 89.07% was achieved at an inhibitor concentration of 4%. Moreover, the new organic inhibitor exhibited good corrosion protection capability for steels under different NaCl concentrations. Its inhibition efficiency was determined to be 65.62, 80.06, and 66.30% at NaCl concentrations of 2, 3.5 and 5%, respectively. On the other hand, it was found that an alkaline environment was favorable for an enhanced corrosion prevention effect, and an optimal pH value of 11.3 was observed in this work. Besides, the inhibition efficiencies at different temperatures showed a trend of 25 > 35 > 40 > 20 > 30 °C, with a maximum value of 81.32% at 25 °C. The above results suggest that the new organic material has high potential to be used as an eco-friendly and long-term durable inhibitor for steel corrosion prevention under complex conditions.

Experimental Investigation of Producer Gas Effects on Coated Pipelines in Biomass Downdraft Gasifier System

Abstract This research examines the performance of epoxy, ceramic, and graphene coatings on stainless steel 316 in a producer gas environment, focusing on corrosion and erosion resistance. This research aimed to identify the most effective coating for applications in harsh gasification environments. In this research, various analyses, including microstructural examination, hardness and weight measurements, FESEM analysis, and EDAX analysis, were conducted to evaluate the performance of the coatings. The producer gas was passed on to all the coated samples for a period of 100 hours. The significant findings include the superior corrosion and erosion resistance of ceramic-coated stainless steel, as evidenced by low weight fluctuations, maintained hardness levels, and elemental stability. Graphene coatings exhibit high hardness but increased porosity, raising concerns about durability, while epoxy coatings are vulnerable to gas-induced structural alterations. The inclusion rating analysis underscored the ceramic coatings' ability to preserve consistent material properties. Overall, ceramic coatings have emerged as the preferred option for gasification environments due to their structural resilience, inclusion integrity, and elemental stability. Considering the inclusion integrity, mechanical strength, weight stability, and elemental stability, ceramic-coated stainless steel 316 samples exhibit better resistance toward producer gas influence. This research contributes valuable insights for material selection in applications exposed to harsh gasification environments, emphasizing the importance of coating selection for long-term durability and performance.

Mechanical properties of products made of corrosion-resistant steels during additive growth by laser sintering and electric arc surfacing

The mechanical properties of products made from 10Х12Н10Т and 08Х18Н9 corrosion-resistant steels are studied during additive growth of powder particles by laser sintering (SLM method) and electric arc surfacing (WAAM method). It is shown that the tensile strength of products obtained by the SLM method is higher than that of rolled samples obtained by the WAAM method. Additional heat treatment of products reduces the tensile strength, but increases ductility properties, especially when manufactured using the WAAM method. An assessment of the influence of structure porosity on the mechanical properties of the metal is given. Keywords:additive growth, corrosion-resistant steels, SLM and WAAM methods, mechanical properties, heat treatment uru.40@mail.ru

Innovative technology for increasing of tool performance when turning difficult-to-cut corrosion-resistant steels

An innovative technology is developed and implemented to increase the performance of turning tools during external machining of corrosion-resistant steels using new coatings for the ВК8 alloy. The performance of the tool is determined by the service life of replaceable standard cutting inserts. The allowable wear of 0,5 mm is accepted on the rear edge. The durability period is increased by up to 3 times without reducing of processing productivity and the quality of the treated surface. Keywords:coating, ВК8 alloy, turning, corrosion-resistant steel, increasing the service life of cutters boris@knastu.ru, avkosm@knastu.ru

Insights into the role of H2O2 on corrosion behavior of NiCu low alloy steel in simulated Beishan groundwater

Steel containers used for geological disposal of high-level radioactive waste will be gradually thinned or even perforated due to corrosion, which will lead to radiolysis of nuclides when they contact with infiltrated groundwater and produce H2O2. This work focused on investigating the influence of H2O2 concentration (0%, 0.001%, 0.01%, 0.1% and 1% by volume) on the corrosion behavior of NiCu low alloy steel as the candidate material for containers was comparatively studied by combining corrosion weight loss test, corrosion product analysis, morphology characterization, thermodynamic analysis and electrochemical measurements. As [H2O2] = 0.001%, H2O2 inhibited the formation of γ-FeOOH and enhanced the compactness of rust layer, which effectively blocked the migration of aggressive ions and slowed down the cathodic reduction reaction of rust, thus improving the corrosion resistance of NiCu steel. With the increase of [H2O2] (0.01%→1%), the cathodic process of NiCu steel corrosion was promoted by the increase of dissolved oxygen involved in cathodic depolarization. Meanwhile, the relative content of Fe3O4 in the rust increased, while Fe6(OH)12SO4 and Fe6(OH)12CO3 decreased obviously, which led to the loose and porous rust layer, thus accelerating the corrosion of NiCu steel.

Enhanced Long-Term Corrosion Resistance of 316L Stainless Steel by Multilayer Amorphous Carbon Coatings.

Diamond-like carbon (DLC) coatings are effective in protecting the key components of marine equipment and can greatly improve their short-term performance (1.5~4.5 h). However, the lack of investigation into their long-term (more than 200 h) performance cannot meet the service life requirements of marine equipment. Here, three multilayered DLC coatings, namely Ti/DLC, TiCx/DLC, and Ti-TiCx/DLC, were prepared, and their long-term corrosion resistance was investigated. Results showed that the corrosion current density of all DLC coatings was reduced by 1-2 orders of magnitude compared with bare 316L stainless steel (316Lss). Moreover, under long-term (63 days) immersion in a 3.5 wt.% NaCl solution, all DLC coatings could provide excellent long-term corrosion protection for 316Lss, and Ti-TiCx/DLC depicted the best corrosion resistance; the polarization resistances remained at ~3.0 × 107 Ω·cm2 after immersion for 63 days, with more interfaces to hinder the penetration of the corrosive media. Meanwhile, during neutral salt spray (3000 h), the corrosion resistance of Ti/DLC and TiCx/DLC coatings showed a certain degree of improvement because the insoluble corrosion products at the defects blocked the subsequent corrosion. This study can provide a route to designing amorphous carbon protective coatings for long-term marine applications in different environments.

Corrosion behaviour and mechanism of acid-resistant steel in acidic solutions with different Cl− concentrations

This study aimed to enhance the corrosion resistance of low-alloy steel in acidic solutions with varying Cl− concentrations. A new acid-resistant steel incorporating Cu and Sb was developed. Various analyses, including immersion tests under different Cl− concentrations and pH values, corrosion weight loss tests, electrochemical tests, morphological observations, and X-ray diffraction (XRD) analysis, were conducted to investigate the corrosion behaviour and mechanism. The results show that in chlorine-containing acidic environments, acid-resistant steel undergoes chemical dissolution at the anode, with hydrogen gas precipitation at the cathode. The corrosion current density is influenced mainly by the pH and immersion time. The primary corrosion products include Fe2O3, Fe3O4, α-FeOOH, γ-FeOOH, Cu, and Sb oxides, and the intensities of the diffraction peaks of Sb2O3 and Sb2O5 increase as the pH decreases. Acid resistance primarily comes from the protective effects of Sb2O3 and Sb2O5. An increase in H+ concentration promotes uniform coverage of Sb2O3 and Sb2O5. A higher H+ concentration has a greater protective effect on the corrosion product layer than does an increased Cl− concentration, although the influence of Cu cannot be ignored.

Comparison of conventional and severe shot peening effects on the microstructure, texture, roughness, hardness, and electrochemical behavior of austenitic stainless steel

In the present research, microstructure, texture, roughness, hardness, and electrochemical behavior of AISI 316L austenitic stainless steel before and after shot peening were studied to elucidate the effect of conventional and severe shot peening (CSP and SSP) processes. After the shot peening, the fraction of strain-induced martensite (SIM) and mechanical twins (MTs) in the sub-surface layer was increased. The fraction of SIM and MTs in the SSP sample was higher than in the CSP sample. The XRD patterns indicated that the SSP sample had a higher peak broadening compared to the CSP sample. In the CSP and SSP samples, a gradient microstructure was formed along the depth direction. The microstructure of the topmost layer of the CSP and SSP samples exhibited numerous ultrafine grains. The grain refining during severe shot peening was faster because of the accumulation of more strain. The CSP and SSP samples revealed a gradient distribution of elements. After the SSP, the intensity of ⟨110⟩‖ED fiber texture decreased from 12.7 to 11.6 × R and the average intensity of ⟨100⟩‖ED fiber texture increased from 1.7 to 2.0 × R, respectively, compared to the CSP sample. The surface roughness of the SSP sample (Rq = 73.6 nm and Ra = 45.2 nm) was lower than that of the CSP sample which represented the roughness decreased with surface coverage increasing from 100 % to 1500 %. Also, the wettability increased after the conventional and severe shot peening processes. In addition, the microhardness of the CSP and SSP samples showed a gradient distribution. The CSP sample had the lowest corrosion current density (0.13 μA/cm2) whereas the NP (non-peened) sample exhibited the highest current density (0.65 μA/cm2). The presence of ⟨100⟩-oriented grains in both CSP and SSP samples led to the higher corrosion resistance of shot-peened steels compared to the NP sample. The presence of favorable texture with higher intensity in the CSP sample was responsible for the higher corrosion resistance of the CSP sample compared to the SSP sample. Finally, the gradient distribution of elements along the depth direction in the CSP and SSP steels improved the corrosion resistance of the surface.

Fabrication of High Corrosion Resistant Stainless Steel Containing Mo-rich Grain

Fabrication of High Corrosion Resistant Stainless Steel Containing Mo-rich Grain

Durability properties and steel corrosion resistance of reinforced concrete using fly ash and ground granulated blast furnace slag as partial replacements for sand and cement

Durability properties and steel corrosion resistance of reinforced concrete using fly ash and ground granulated blast furnace slag as partial replacements for sand and cement

Effect of seawater flow velocity in South Malang on the corrosion rate of low carbon steel with a corrosion coupon rack

Corrosion is a phenomenon of damage to metal that can be influenced by several factors, including environmental factors, namely pH, humidity, temperature, and impurity factors. Corrosion that occurs due to the flow of a fluid is known as erosion corrosion. One type of metal that is susceptible to corrosion is carbon steel. Carbon steel material is very commonly used in the industrial world. An application of carbon steel is in piping systems that transport fluids; thus, fluid flow velocity affects the corrosion resistance of carbon steel. This research aimed to determine the effect of seawater flow on the corrosion rate of low carbon steel (ST 37) with variations in seawater velocity. This research is a type of laboratory-scale experimental research using coupon rack corrosion test equipment. The variations in seawater velocity used are 0 L/min, 15 L/min, 20 L/min, and 25 L/min. Observations of each experiment were carried out every 6 and 12 hours. The corrosion rate was analyzed using the weight loss method, namely by calculating the initial and final weight of the specimen before and after the experiment. The results show that increasing seawater flow velocity also increases the corrosion rate on steel specimens, with the lowest corrosion rate at 10.262 mpy on specimens with a variation of 0 L/min, while the highest corrosion rate is 48.743 mpy on specimens with a variation of 25 L/min. It can be concluded that the velocity of the fluid flow and the type of particles contained in the flow affect the rate of erosion-corrosion. The higher the fluid flow velocity and the more abrasive the particles contained in the flow, the faster the rate of erosion-corrosion.