Improved Corrosion Resistance Research Articles

Design, microstructure, wear and corrosion behaviors of laser clad FeNiCoCrMo0.3Nbx hypoeutectic high entropy alloys coatings

FeNiCoCrMo0.3Nbx (x = 0.15, 0.40 and 0.55 in molar ratio) hypoeutectic high entropy alloys (HEAs) coatings are prepared by laser cladding (LC) designed by binary eutectic composition strategy. Nbx HEAs coatings present FCC + Laves duplex. Under the joint action of various strengthening mechanisms, the average microhardness of Nb0.15, Nb0.40 and Nb0.55 coatings is as high as 480.5 ± 7, 510.2 ± 6 and 540.6 ± 5 HV0.2, respectively. The unique fluctuating oxide film of the HEAs coatings plays a role in reducing wear, with the specific wear rates of 0.37 × 10−4, 0.22 × 10−4 and 0.18 × 10−4 mm3/Nm for Nb0.15, Nb0.40, and Nb0.55 cladding layers, respectively. The Nbx HEAs coatings displayed excellent corrosion resistance in 0.5 M H2SO4 solution. For Nb0.15 and Nb0.40 HEAs coatings, the increase of Nb promotes the formation of passivation film and improves corrosion resistance. However, the higher dislocation density intensifies the chemical inhomogeneity of the alloy due to excessive addition of Nb, which is not conducive to the corrosion resistance of Nb0.55 HEAs coating. The Nb0.40 cladding layer exhibits better corrosion resistance, and the Icorr is only 1.24 ± 0.6 μA/cm2. Combined with Mott-Schottky (M-S) test, the carrier densities (ND) of three HEAs coatings are increased in the order of Nb0.40 (1.09 × 1021 cm−3) < Nb0.15 (1.83 × 1021 cm−3) < Nb0.55 (3.57 × 1021 cm−3), indicating that the strong protective passivation film is also a key factor to achieve better corrosion resistance.

The effect of three types of heat treatment on the hardness and corrosion resistance of Al 2014 alloy

AbstractAl 2014 is a high‐strength aluminum alloy widely used in the aerospace and automotive industries for its mechanical strength. This research examines the effects of three heat treatment processes—retrogression and re‐aging (RRA), T6 standard aging, and a modified RRA with high‐temperature pre‐aging—on the hardness and corrosion resistance of Al 2014. Polarization studies using potentiodynamic electrochemical methods in a 3.5 wt% sodium chloride solution were conducted to evaluate the corrosion resistance. The results showed that heat treatment, which causes precipitation hardening, shifted the corrosion potential (E) toward a more noble direction. The formation of Al2Cu precipitates is associated with improved corrosion resistance. Additionally, samples treated with the T6 process exhibited a higher corrosion current density compared to untreated Al 2014 alloy samples, indicating superior corrosion resistance. Analysis of corroded surfaces using scanning electron microscopy (SEM) with energy‐dispersive X‐ray spectroscopy (EDS) showed evidence of general and pitting corrosion, with distinct patterns among the three heat treatment processes. A comparison of the results revealed that the T6 standard aging process provided the best combination of hardness and corrosion resistance. This was likely due to the formation of stable precipitates during aging. The results also indicated that the RRA process showed good performance, suggesting it is a viable alternative when a balance between hardness and toughness is required. The modified RRA with high‐temperature pre‐aging resulted in lower performance, likely due to overaging, which reduced hardness and corrosion resistance. These findings highlight the significance of heat treatment in improving the corrosion resistance of Al 2014 alloy. This suggests that particular processes can enhance the alloy's durability in corrosive environments, potentially leading to a longer lifespan and reduced maintenance costs. The T6 standard aging process offers the best balance of enhanced hardness and corrosion resistance for Al 2014 alloy, making it ideal for extending lifespan and reducing maintenance costs in corrosive environments. Careful selection of heat treatment is crucial based on specific alloy performance requirements.

Nanostructured multilayer Cr/CrN coatings on 316L stainless steel for proton exchange membrane fuel cell bipolar plates

Nowadays, hybrid surface modification approaches offer tailored solutions for improving the corrosion resistance and electrical conductivity of the bipolar plates (BPPs) in proton exchange membrane fuel cells (PEMFCs). In the present study, a combination of plasma nitriding and physical vapor deposition (PVD) processes was used to apply a nanometric Cr/CrN multilayer coating onto 316L stainless steel (SS316L) bipolar plates. The performance of the resulting plasma nitrided, PVD-coated, and combined plasma nitriding/PVD-coated SS316L BPPs was examined by phase and morphological characterizations, surface wettability measurements, interfacial contact resistance (ICR), and electrochemical investigations. Potentiodynamic and potentiostatic polarization evaluations, electrochemical impedance spectroscopy (EIS) and Mott-Schottky asessments were conducted on the coated samples in a simulated PEMFC cathode environment at temperatures of 25 °C and 75 °C. Results indicated that the Cr/CrN multilayer coating deposited on the plasma-nitrided 316L BPP exhibited a remarkable 100-fold improvement in corrosion resistance compared to the uncoated substrate. Also, the combination of nitriding and PVD resulted in a significant reduction of the ICR from 186 mΩ cm2 for the uncoated SS316L to 10.2 mΩ cm2 for the coated sample. Multilayer coatings based on the combination of plasma nitriding and PVD treatment can identified as promise candidates for BPP applications.

Influence of the current density on the properties of electrodeposited Ni-W- Ti2AlC composite coatings

In this work, Ni-W-Ti2AlC composite coatings with anti-wear and anti-corrosion abilities were prepared using direct current electrodeposition. The study primarily focuses on the influence of different current densities on the structure and properties of Ni-W-Ti2AlC composite coatings. The microstructural, mechanical properties, and electrochemical performances were studied by using SEM, XRD, EDS, and Tafel polarization techniques. The results indicated that Ti2AlC is successfully co-deposited into the Ni-W coating, and the average grain size of the Ni-W-Ti2AlC composite coating is 15.2 nm. The significant improvement in hardness, wear resistance, and corrosion resistance of Ni-W-Ti2AlC composite coating is attributed to the effects of solid solution strengthening and the uniform distribution of the microstructure. The suitable current density has a great influence on the properties. The microhardness of Ni-W-Ti2AlC composite coatings was increased by 99.59% at a current density of 5 A dm−2 compared to 3 A dm−2. At the same time, the friction coefficient decreased by 13.89%.

Silver-doped ZrO2-TiO2 nanocomposite coatings on 316L stainless steel for enhanced corrosion resistance and bio applications

The demand for ceramic based nanocomposite coatings has increased because they play a significant role in orthopedic implants and medical devices. Ceramic nanocomposites are inert and highly biocompatible, which improve corrosion resistance under physiological fluids. The ceramic nanocomposites were deposited (silver-doped ZrO2/TiO2) on SS 316L, and their biocompatibility, strength of adhesiveness, and corrosion resistance properties were studied. A detailed investigation of corrosion resistance, wettability, and biocompatibility concerning microstructures and the inclusion of silver as a dopant was conducted. The deposited films annealed at 600 °C display crystallinity with the coexistence of TiO2 rutile and ZrO2 monoclinic phases. The surface morphology shows the average particle size on thin film is around 40 to 45 nm. The deposited films show a decreased corrosion current density (ICorr) in potentiodynamic polarization curves, confirming the adequate protection against corrosion using simulated body fluid and phosphate buffer saline at 37±1 °C. The surface wettability of coatings is hydrophilic, and it improves in-vitro compatibility. The apatite growth in SBF solution on the implant surface predicts a favorable condition for bone regeneration in the patient's body. The effect of silver dopant on improving apatite growth on implant surface is also discussed. From electrochemical impedance spectroscopy, the diameter of the semicircle in the Nyquist plot shows more than bare metal; the higher the diameter indicates the more resistive behavior of deposited films, which shows the effective corrosion resistance in the electrolytic solution. It is found that the biocompatibility and corrosion resistance are improved compared with bare SS 316L. Hence, ceramic nanocomposite coatings show great potential in the orthopedic implant industry.

Effect of post-processing on the corrosive behaviour of L-DED Ti-6Al-4V

The study investigates the effect of different post-processing techniques like annealing and cryogenic treatment on the corrosive behaviour on Laser direct energy deposited − Ti-6Al-4 V (LDED-Ti64). The investigation starts with LDED-Ti64 and cast-Ti64, one pair of samples are annealed at 800℃ for 2 h and the other pair of samples are Deep Cryogenic Treated(DCT) at −196℃ for 48 h. The electrochemical corrosion of all the samples are analysed through the tafel extrapolation technique. The results revealed that all the post-processed samples showed improvement in corrosion resistance, especially the annealed ones in comparison to the untreated sample. During annealing the martensitic α’-phases present in untreated samples get converted to β-phase which is a good corrosion inhibitor. During DCT the residual stress relieves and dislocation density improves which restrains electron flow and hence corrosion resistance improves.

Effect of reinforcement particle size on the corrosion and mechanical properties of spark plasma sintered aluminium matrix composites.

In this study, the effects of different sizes of reinforcing particles on the corrosion behaviour and mechanical properties of aluminium (Al)-based composites produced by spark plasma sintering (SPS) are analysed. In the study, the effects of SPS parameters, including electrical power, applied pressure and sintering temperature, on the consolidation process and microstructure evolution of the composite are closely investigated. The results reveal a nuanced relationship between the sintering conditions and the properties of the particles, which in turn determine the sintering dynamics and the formation of the microstructural features. The evaluation of mechanical properties indicates a remarkable influence of particle size distribution on the hardness of the composites, showing an initial improvement with the introduction of nanoparticles, followed by a slight decrease as the balance between nano- and micron-sized Al2O3 particles shifts. A scanning electron microscopy (SEM) study demonstrates the influence of particle dimensions on the change of grain boundaries and the spatial arrangement of the composite matrix. Electrochemical experiments in a 0.1M NaCl solution show a consistent corrosion potential (Ecorr) across all samples, while the current densities associated with corrosion (icorr) show considerable variation. The presence of nano-sized Al2O3 particles was found to increase corrosion resistance, in contrast to the detrimental effects observed with larger microparticles. In particular, composites with a bimodal distribution of particle sizes showed a 3.5-fold increase in corrosion resistance compared to pure Al. The specific Al-2n8mAl2O3 composite that exhibited active electrochemical properties at elevated potentials without a defined passivation range emphasises the significant role of particle size. This study draws attention to bimodal microstructures as a promising route to achieving uniformity and improved corrosion resistance in Al matrix composites, while pointing to the need for further research to fully elucidate the operative mechanisms.

New insights for composition design: A novel synergistic corrosion-resistant effect of Fe–Mn–Al–Cr–Si–Mo–C lightweight steel in 3.5 wt% NaCl solution

Nowadays, a good corrosion resistance of lightweight steel is demanded for its application. However, due to the high contents of Mn and C, which are always corrosion-susceptible elements in steels, the conventional lightweight steel is not desirable for this mission. Although Cr is widely believed to be a common alloying element to improve the corrosion resistance of most steels, it is considered to be ineligible using in the lightweight steel due to the relatively high content of C. This is because the trade-off between corrosion resistance and mechanical properties by alloying Cr. In recent years, the rapid developments of additive and coating manufacturing have provided new possibilities for both the Cr alloying and microstructural modulation to improve corrosion resistance of lightweight steel. In this case, to design a certain chemical composition using in additive and coating manufacturing, it is interesting to clarify the effects of Cr alloying on the corrosion resistance of lightweight steel. To reveal it, in the present work, the Fe–Mn–Al–Cr–Si–Mo–C lightweight steel alloyed with Cr contents of 4 wt%, 8 wt% and 12 wt% are prepared. The corrosion resistances and mechanisms of Cr-alloyed lightweight steels in 3.5 wt% NaCl solution are investigated by electrochemical and immersion tests. The present work may provide new insights for the composition design of lightweight steel, especially for the directions of additive and coating manufacturing.

Effect of Nitrogen on Precipitate Characteristics and Pitting Resistance of Martensitic Stainless Steel.

High-carbon-chromium martensitic stainless steel (MSS) is widely used in many fields due to its excellent mechanical properties, while the coarse eutectic carbide in MSS deteriorates corrosion resistance. In this work, nitrogen was added to the MSS to improve corrosion resistance. The effects of nitrogen on the microstructure and corrosion resistance of MSS were systematically studied. The results showed that the addition of nitrogen promoted the development of Cr2N and reversed austenite, effectively inhibiting the formation of δ-ferrite. Therefore, the durability of the passivation film was improved, the passivation zone was expanded, and the susceptibility to metastable pitting was decreased. As a consequence, nearly two orders of magnitude have been achieved in the pitting potential (Epit) of MSS containing nitrogen, and the polarization resistance value (Rp) has gone up from 4.05 kΩ·cm2 to 1.24 × 102 kΩ·cm2. This means that in a corrosive environment, nitrogen-treated MSS stainless steel is less likely to form pitting pits, which further extends the service life of the material.

Laser processing effects on Ti−45Nb alloy surface, corrosive and biocompatible properties

The Ti−45Nb (wt.%) alloy properties were investigated in relation to its potential biomedical use. Laser surface modification was utilized to improve its performance in biological systems. As a result of the laser treatment, (Ti,Nb)O scale was formed and various morphological features appeared on the alloy surface. The electrochemical behavior of Ti−45Nb alloy in simulated body conditions was evaluated and showed that the alloy was highly resistant to corrosion deterioration regardless of additional laser surface modification treatment. Nevertheless, the improved corrosion resistance after laser treatment was evident (the corrosion current density of the alloy before laser irradiation was 2.84×10−8 A/cm2, while that after laser treatment with 5 mJ was 0.65×10−8 A/cm2) and ascribed to the rapid formation of a complex and passivating bi-modal surface oxide layer. Alloy cytotoxicity and effects of the Ti−45Nb alloy laser surface modification on the MRC-5 cell viability, morphology, and proliferation were also investigated. The Ti−45Nb alloy showed no cytotoxic effect. Moreover, cells showed improved viability and adherence to the alloy surface after the laser irradiation treatment. The highest average cell viability of 115.37% was attained for the alloy laser-irradiated with 15 mJ. Results showed that the laser surface modification can be successfully utilized to significantly improve alloy performance in a biological environment.

Preparation and investigation of Ni-W/CeO2 composite coating and its structure and anti-corrosion properties with different ceria content and deposition time

In the current work, CeO2 nanoparticles were embedded in Ni-W alloy matrix by pulse electrochemical deposition on copper substrate to optimize their microstructure and corrosion resistance. The effects of CeO2 concentration and deposition time on Ni-W/CeO2 composite coating were investigated for optimized structure and improved corrosion resistance. The composite coatings present nodular-like surfaces with dense and compact growth profiles, containing 63.03–67.88 wt% Ni, 28.73–31.87 wt% W and 0.25–8.24 wt% Ce. The content of incorporated CeO2 in coatings increased with the increase of CeO2 concentration in electrolyte. The addition of CeO2 particles has refined the grains of the prepared coating. The surface became rougher with the extension of electrodeposition time. Ni-W/CeO2 composite coating electrodeposited at 10 g L−1 CeO2 for 60 min possessed the highest corrosion resistance, indicating enhanced corrosion protection and long-term stability. This premium coating can be applied in harsh environments to prolong the lifespan of machinery, equipment, and parts in marine, vehicle, aerospace, and chemical industries.

Significant improvement in hot corrosion resistance of Inconel 690 by laser shock peening

The effects of laser shock peening (LSP) with different peening times on the hot corrosion behavior (molten salt of 75 wt% Na2SO4 + 25 wt% NaCl) of Inconel 690 at three different temperatures (700 °C, 800 °C, 900 °C) were investigated. The corrosion conditions of the three specimens were also compared in the extreme case, i.e. after 900 °C, 300 h of hot corrosion. The results showed that LSP effectively prevented the surface oxides from shedding. As times of LSP increased, the strengthening effect improved and the rate of weight loss gradually slowed down. The dense oxide film generated by the high Cr content of the material itself, LSP-induced high-density dislocation structure, mechanical twinning and grain refinement is one of the key factors in improving the hot corrosion resistance of Inconel 690. The CRS layer and microhardness layer are another key factor in preventing the cracking of the oxide film to enhance the hot corrosion resistance. Under extreme conditions, the hot corrosion resistance of LSPed specimens is still better than that of unLSPed specimen.

CeO2/SWCNT nanocomposite coating: A novel approach for corrosion application

AbstractThe coatings were prepared by blending different concentrations of SWCNTs and CeO2 particles with an epoxy resin by hydrothermal method, which was then applied to the substrate through the doctor blade technique. The mixtures were transferred into a 1‐L capacity autoclave with a teflon‐lined flange type and subjected to hydrothermal treatment at 100°C for 3 h. The surface coatings were applied using a doctor blade. Subsequently, the coated materials were placed in an oven and dried for 12 h at 50°C under vacuum conditions. The samples' structural analysis was examined through x‐ray diffraction (XRD). XRD analysis verified the CeO2/SWCNT composite coating, and Fourier transform infrared spectroscopy (FTIR) was utilized to assess the presence of functional groups. Thermodynamic properties and thermal stability of composite coatings that were modified with SWCNTs and CeO2 particles were studied by thermogravimetric analysis (TGA). The impact of the CeO2/SWCNT composite on the anticorrosion capabilities of the epoxy coating was examined through electrochemical impedance spectroscopy (EIS), Nyquist curve, and Tafel slope characterization. Corrosion tests were conducted on the CeO2/SWCNT composite coatings in a 3.5 wt% sodium chloride (NaCl) solution at 25°C to improve corrosion resistance. The concentration of 0.4 wt% CeO2 was found to be optimal for achieving effective corrosion resistance. The composite coating CNT0.6‐C0.4 exhibited significantly higher Ecorr (−426 V) and lower Icorr (2.96 × 10−6 A cm−2) values compared to samples from the CNT0, CNT0.2, and CNT0.6 groups. The paper presents a viable solution with CeO2/SWCNT composite coating for the engineering application of corrosive‐inhibiting coatings.

Improved corrosion resistance of hydroxyapatite-reinforced plasma electrolytic oxide coatings on AZ31 alloy from one-step and two-step fabrications

The improved corrosion resistance of AZ31 alloy by plasma electrolytic oxidation (PEO) counteracts its apatite-forming ability. To overcome the issue, apatite-containing coatings were fabricated. One-step and two-step fabrications were compared to incorporate the nanoparticle hydroxyapatite (HA) in the coating and to evaluate their effect on the corrosion resistance. The corrosion resistance was evaluated by polarization test and EIS measurement in 0.9% NaCl solution. The electron microscopy and chemical analysis revealed that the HA particles were dispersed in the one-step coatings, while an interspersed HA distribution was observed in the two-step coatings. The dispersed particles enhanced the coating’s hardness from 490 to 554 HV. In the two-step coatings, the HA particles mainly accumulated inside the pores, reducing the coating porosity down to 3.9%. The one-step coatings were more stable in the corrosive solution, offering a remarkably higher corrosion resistance, than the two-step coatings. Moreover, the one-step coating required a shorter (half) processing time (10 min) than the two-step process (20 min) to achieve a similar order of corrosion current density of 10−7 A cm−2. The results demonstrated that the arrangement of reinforcement in the PEO coatings and its effect on the corrosion resistance can be adjusted.

Improved corrosion resistance of powder manufactured AISI 904L parts by hot isostatic pressing post treatment

Improved corrosion resistance of powder manufactured AISI 904L parts by hot isostatic pressing post treatment

The corrosion behavior of AZ91 bulk alloy and thin films

PurposeThe purpose of this study is to campare the corrosion behavior of Az91 films and bulk sample, in the objective to provide reference for the corrosion resistance improvement of Mg alloys.Design/methodology/approachAZ91 films with various thickness values are produced by magnetron sputtering technique, and the corrosion behavior was characterized by immersion tests and electrochemical measurements.FindingsThe AZ91 films exhibited a preferred orientation with basal planes parallel to the surface and increased densification with the increase of thickness, and a superior corrosion resistance for the AZ91 films compared with the bulk sample.Originality/valueThe preferred (0002) basal planes in AZ91 films benefited the corrosion resistance and the nanoscale AZ91 films facilitated the development of a dense passivation film. Consequently, AZ91 film exhibited a superior corrosion resistance.

Enhancing color tunability and corrosion resistance of ZrO2 hard coatings via embedding Si multilayer films

ZrO2 coatings are widely employed to protect metal substrates from corrosion. However, achieving anti-corrosive ZrO2 coatings that also exhibit the full color range remains a significant challenge. Using the magnetron sputtering, the present study applied a ZrO2/Si multilayer coating to the 304 stainless steel, incorporating Si interlayers within a ZrO2 monolayer coating. The influence of incorporated Si interlayers on the morphology, structure, hardness, optical properties, and corrosion resistance of the ZrO2 coatings was systematically investigated. Application of Si interlayers effectively mitigated the development of columnar structure and pinhole defects in the ZrO2 coatings. This led to a reduction in the surface cluster size from 300 to 50 nm and the average grain size of ZrO2 from 20.3 to 15.7 nm. As a result, ZrO2 coating exhibited significant improvement in corrosion resistance. After adding Si interlayers, the corrosion current density of the ZrO2 coating dropped from 3.76 × 10-6 to 4.69 × 10-8 A/cm2 in 1 mol/L H2SO4 solution, while it dropped from 6.81 × 10-8 to 2.57 × 10-10 A/cm2 in 3.5 wt.% NaCl solution. The ZrO2/Si multilayer coatings exhibited different colors, including red, orange, yellow, green, blue, indigo, and purple. These colors were achieved by varying the thickness of the ZrO2 top layer, which was set at 240, 220, 210, 190, 175, 160, and 150 nm, respectively. The present study provided detailed insights into the color tuning capability and the enhanced corrosion resistance of ZrO2/Si multilayer coatings.

Eggshell derived hydroxyapatite reinforced nickel electrodeposition via post-supercritical-CO2 approach: Enhanced electrochemical corrosion resistance for seascape applications

The corrosion resistance of brass materials, commonly used in PCBs, MEMS, and the automobile industry, is significantly compromised in chlorine-containing environments prevalent in marine, chemical, and petroleum industries. To address this issue, we proposed the development of a nickel/hydroxyapatite (Ni/HAP) composite coating using a post-supercritical carbon dioxide (post-SC-CO2) approach, aiming to enhance corrosion resistance compared to conventional methods. The study evaluates the effectiveness of the post-SC-CO2 process against SC-CO2 and conventional electrodeposition techniques. The fabricated Ni/HAP coatings are examined through various physico-chemical characterizations to elucidate their surface morphology, phase purity, and chemical compositions. The surface morphology of Ni/HAP coating from post-SC-CO2 method features micro-cones, indicating SC-CO2 phenomena at atmospheric pressure. The electrochemical impedance spectroscopy analysis demonstrates that the conventionally electrodeposited Ni/HAP coating attains a corrosion resistance of 4.331 × 104 Ω cm2, 31.59 % enhancement in protection efficiency compared to a standalone Ni coating. In contrast, coatings fabricated using SC-CO2 and post-SC-CO2 methods exhibit corrosion protection efficiencies that are 92.97 % and 70.84 % higher, respectively, compared to the conventional electrodeposition technique. These findings highlight the superior performance of the post-SC-CO2 electrodeposition method in improving corrosion resistance, indicating its significant potential for industrial applications.

Enhanced corrosion resistance of Ti[sbnd]Al[sbnd]Mo alloy through solid state transformation driven by rapid solidification

Rapid solidification of undercooled liquid Ti50Al44Mo6 alloy was realized by electromagnetic levitation. Primary (βTi) dendrite grew rapidly from melt with decreasing temperature. As undercooling increased, nucleation rate and growth driving force of primary (βTi) dendrites increased. Growth velocity of primary (βTi) dendrite increased significantly, reaching 13.5 m·s-1 at the maximum undercooling (233 K). After solidification, primary (βTi) dendrite decomposed simultaneously through β→α→α2 transformation and martensite transformation β→γ. Homogeneity of solute distribution in primary (βTi) phase affects the solid-state phase transformation mode. Solid-state phase transition was mainly dominated by diffusion-controlled β→α→α2 transformation at small undercooling. Solid-state phase transition gradually was dominated by displacive martensite transformation at deep undercoolings, and corresponding microstructure was mainly characterized by more refined martensite needles. The refined microstructure and martensite transformation domination contributed to the formation of passivation films with improved corrosion resistance. Moreover, this weakens micro-galvanic effect, significantly reduces size of pits, maintains corrosion scales over pits to effectively alleviate the corrosion process, and consequently enhances corrosion resistance.

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.