The corrosion behavior of hot-press-formed (HPF) B-pillar components fabricated from Al-Si-coated boron steel was investigated with an emphasis on the forming-induced crack morphology. The specimens were extracted from the inner and outer surfaces of the top, flat, and radius regions. Microstructural characteristics and coating cracks were examined using optical microscopy, as well as field-emission scanning electron microscopy (FE-SEM) in combination with energy-dispersive spectroscopy (EDS), and corrosion behavior was evaluated using cyclic corrosion immersion and potentiodynamic polarization tests in a 3.5 wt.% NaCl aqueous solution. The Al-Si coating exhibited a multilayered structure composed of alternating Al- and Fe-rich layers. The crack morphology strongly depended on the local stress state: wide macrocracks were mainly formed on the outer surface of the radius region under tensile deformation, whereas the narrow microcracks predominated on the inner surface subjected to compressive deformation. Cyclic corrosion immersion tests showed that the corrosion propagated preferentially along the coating cracks and was more severe on the inner surfaces, where narrow microcracks promoted aggressive crevice corrosion owing to chloride ion accumulation and local acidification. By contrast, wider macrocracks on the outer surface mitigated crevice corrosion by allowing electrolyte exchange. Potentiodynamic polarization tests indicated similar corrosion rates for all regions; however, the outer radius region exhibited a relatively noble corrosion potential owing to oxide film formation on the locally exposed substrate areas. These results demonstrate that the crack morphology induced by curved forming is a key factor governing the corrosion behavior of HPF B-pillar components.

The effect of cold deformation on crevice corrosion and stress corrosion cracking behavior of 304 stainless steel

Purpose The purpose of this study is to investigate the susceptibility of L80, and other steels with 1% Cr, 3% Cr and 9% Cr, to stress corrosion cracking (SCC), pitting, crevice and stress concentration effect at the existing conditions of an oil reservoir. Design/methodology/approach The 4-points bent beam specimens were employed in the experimental works. The experimental works were performed at 82°C in a simulated environment that contains CO2 and Cl−. The effect of stress concentration on corrosion rate was confirmed by the novel circumferential notched tensile (CNT) specimen approach. Findings The results indicate that these steel grades are not susceptible to SCC in the given condition, and are promising materials for the application. The L80, 1% Cr and 3% Cr steels were attacked by pitting and crevice corrosion, while the 9% Cr steel was insignificantly affected, presumably due to its higher Cr, Mo and Ni contents. The local corrosion concentrated on sites that have high stress concentration. The CNT specimens confirmed the effect of stress concentration on promoting the local corrosion. Originality/value The study provides an essential insight into the susceptibility of downhole tubular to SCC for L80, 1% Cr, 3% Cr and 9% Cr steels in simulated reservoirs environment that contains CO2 and Cl−. A novel fracture mechanics approach using the CNT specimen method was introduced in investigating the effect of stress intensity on corrosion rate.

Copper-nickel 90/10 alloys are widely used in marine environments due to their resistance to corrosion and biofouling. However, the influence of macrofouling on localised corrosion remains poorly understood. This study examines the effect of simulated macrofouling-induced crevices on CuNi 90/10 corrosion using laser-cut plastic shims to replicate hard fouling geometries. Samples with crevice gaps of 50, 130 and 1,000 µm were exposed for 180 days at two Australian marine sites: temperate (Melbourne) and tropical (Cairns). Crevice corrosion was most severe in Melbourne, with the 130 µm gap showing the deepest attack. In Cairns, samples showed lower crevice corrosion despite heavier external fouling, suggesting that fouling composition and protective calcareous deposits may mitigate attack. Crevice interiors lacked Desulfobacterota and exhibited less diverse communities with greater inter-replicate variability at both sites than outside surfaces. These results highlight the combined influence of environment, crevice geometry, corrosion product films, and biofouling composition on crevice corrosion of CuNi 90/10.

Corrosion is a naturally occurring electrochemical degradation process that imposes severe economic and safety burdens on modern society by reducing the service life of metallic infrastructures in transportation, marine systems, electronics, and energy industries. From a fundamental standpoint, corrosion represents a spontaneous chemical reaction governed by thermodynamic feasibility and electrochemical kinetics, where the driving force is often explained through the Second Law of Thermodynamics and the relative stability of oxidation states in aqueous environments. Accordingly, standard reduction potentials provide an effective framework for predicting the tendency of metallic dissolution and cathodic reduction reactions under practical conditions. This review summarizes the fundamental principles of corrosion, including major corrosion forms such as uniform corrosion, galvanic corrosion, pitting, crevice corrosion, intergranular corrosion, and stress corrosion cracking. A critical discussion is presented on conventional corrosion mitigation strategies, including inhibitors, cathodic protection, alloying, surface passivation, and protective coatings. Particular emphasis is placed on graphene as an emerging corrosion-resistant material due to its high chemical stability, mechanical strength, and exceptional impermeability to aggressive species. The role of graphene as a diffusion barrier is analyzed in terms of defect density, interfacial adhesion, and microstructural integrity. Furthermore, recent progress in nickel–graphene composite coatings is reviewed, highlighting their improved barrier properties, grain refinement effects, enhanced polarization resistance, and suppression of localized corrosion processes. Finally, current challenges and future research directions are outlined, focusing on scalable fabrication, dispersion stability, long-term durability, and the development of multifunctional graphene-enabled anticorrosion coatings for industrial deployment.

Purpose The purpose of this paper is to investigate the influence of solution acidification on corrosion behavior of 316L stainless steel (SS) in simulated crevice environment. Design/methodology/approach In this paper, the double electrolytic cell device was used to simulate the different environment inside and outside of the crevice, and the effect of solution acidification inside the crevice on the crevice corrosion of 316L SS was investigated by electrochemical measurement and microstructure observation. Findings The results shows that the positive shift in the potential of the 316L SS inside the crevice due to the significant galvanic effect between the inside and outside of the crevice generate the passive effect facilitating the formation of passive films. However, the passive effect only mitigates the development of corrosion to a certain extent. In the weak acid environment, pitting corrosion occurs on the 316L SS inside the crevice. With the continuous acidification of the solution, the passive effect of 316L SS within the crevice weakens and corrosion intensifies. Finally, the environment factor plays the predominate role in the strong acid environment, leading to overall thinning of the 316L SS within the crevice. Originality/value The research findings further elucidates the mechanism of crevice corrosion of SS in seawater and provides valuable insights for the practical application of SS in marine engineering equipment.

Effects of the chloride ion concentration on the crevice corrosion behavior of 316 L stainless steel

Crevice corrosion behavior of Ti-6Al-4V alloy in simulated inflammatory environment for biomedical applications

Cariogenic Streptococcus mutans accelerates the crevice corrosion of 316L stainless steel in simulated oral environment.

Purpose This study aims to investigate corrosion mechanism of titanium–steel composite plates in simulated marine environments. Design/methodology/approach Corrosion behavior of TA2/Q345B composite plates was investigated via immersion test. Corrosion product was analyzed by scanning electron microscopy combined with energy-dispersive spectroscopy, X-ray diffraction, potentiodynamic polarization tests and electrochemical impedance spectroscopy. Findings Corrosion near the interface region originated from galvanic corrosion and later transformed into a combination of galvanic corrosion and crevice corrosion. The accelerating effect of galvanic corrosion in the far-interface region has been weakened, its corrosion behavior is similar to the self-corrosion behavior of carbon steel in the marine environment. Originality/value Research on corrosion behavior of titanium-steel composite plates is not sufficient. It is necessary to understand their corrosion mechanism, especially the reasons for differences in corrosion behavior between the near-interface region and the far-interface region.

Metal Release in Total Knee Arthroplasty: A Review of Mechanisms, Adverse Local Tissue Reactions, and Biological Effects.

Duplex stainless steels (DSSs) have outstanding mechanical properties and corrosion resistance. However, operating conditions and/or inadequate heat treatments can induce precipitation of deleterious phases or change the proportion of ferrite (α) and austenite (γ) phases. This study evaluates the impact of ageing at 850 and 950 °C and solubilization at 1000 and 1150 °C treatments on pitting and crevice corrosion of DSS UNS S32205. Cyclic polarization tests revealed that samples with a more balanced α/γ ratio (≈50/50), that is, the base material (BM) and that solubilized at 1000 °C, exhibited the lowest corrosion rate (0.044–0.074 μm/year) and better repassivation capacity (E R ≈ 0.96 V). Conversely, the 1150 °C treatment led to reduced corrosion resistance (0.158 ± 0.009 μm/year) and is associated with a reduction in the %Cr in α. Pitting is present in the aged conditions only. Moreover, the BM and 1000 °C samples showed the lowest crevice corrosion susceptibility, presenting the lowest volume loss (1 × 10 6 μm 3 cm −2 ) and current densities (≈1000 μA cm −2 ), followed by samples treated at 1150, 950, and 850 °C. Therefore, the results show that ageing treatments make UNS S32205 susceptible to pitting and crevice corrosion, which is related to the deleterious phase fraction and the α/γ ratio imbalance.

Abstract Corrosion failure of transformer terminal connection components poses a severe threat to the service safety of power equipment in coastal regions. This study employs neutral salt spray corrosion testing to simulate the high-temperature summer conditions along Guangzhou’s coastline, investigating the corrosion behaviour of H59 brass transformer wiring clamp. Results indicate that corrosion intensifies under the synergistic effects of galvanic and crevice corrosion when H59 brass is connected to galvanized bolts, with the hot-dip galvanized bolt connection group exhibiting the most severe corrosion. The primary corrosion products of H59 brass in salt spray environments are Cu 2 O and ZnO. However, following connection with galvanised bolts, the Cu 2 O phase disappears due to the participation of coating elements in the reaction, with additional oxides such as Sn 2 O appearing. Compared to the loose ZnO, the ability of H59 brass to form dense Cu 2 O may be key to its resistance to salt spray corrosion.

Improvement of crevice corrosion resistance of TA17 titanium alloy by active screen plasma nitriding after surface nanocrystallization

The effect of fluoride ion on crevice corrosion of Ti-6Al-3Nb-2Zr-1Mo alloy in NaCl solution

The susceptibility of P110 steel to crevice corrosion was initially assessed in 10% CO2-saturated shale oil produced solution by using weight-loss measurements and surface analysis, simulating corrosion induced by CO2 leakage at the casing-cement interface. Subsequently, the crevice corrosion kinetics was investigated by electrochemical techniques. All corrosion experiments demonstrated that corrosion occurred once a crevice was physically created. However, the corrosion behavior differed from classic critical crevice solution and IR drop crevice corrosion theories, which typically involve acidification, destruction of corrosion produce and an acceleration of corrosion inside crevice. In this study, hydrogen reduction is employed as the cathodic reaction rather than oxygen reduction. Surface morphology and protectiveness of the corrosion product formed inside crevice are different from that outside crevice. A thin and well-crystallized corrosion product formed inside crevice, whereas a thick layer of corrosion product without discernable crystallinity was visible outside crevice. A distinct difference was noticed in the three crevice areas where slight corrosion was inside crevice, but severe corrosion occurred outside crevice, and a deep groove appeared at the crevice mouth. The strong galvanic effect between inside and outside crevice triggered crevice corrosion. The electrode inside crevice acted as the cathode, and the electrode outside crevice worked as the anode, with the potential difference between them increasing over time. The crevice corrosion phenomenon in this study is attributed to alkalization inside crevice, and a corresponding mechanism is proposed. Crevice corrosion may diminish or even vanish in the long-term operation of shale oil fields after supercritical CO2 fracturing if the cathode and anode do not reverse over time.

The C01 type diaphragm coupling demonstrates effective performance in high-concentration seawater salt fog environments. However, the fastener material for this coupling must possess high mechanical properties and strong resistance to seawater corrosion. This study evaluates the suitability of 17−4 precipitation hardening (PH) stainless steel for diaphragm coupling fasteners through a series of tests, including pitting corrosion, crevice corrosion, stress corrosion, fatigue, galvanic corrosion, and cyclic immersion. The results show that the weight loss of 17−4PH stainless steel sample is 13.71% after pitting test and 7.73% after crevice test. However, after stress corrosion, fatigue, and galvanic corrosion tests, the 17−4PH stainless steel sample exhibits minimal corrosion sensitivity. These findings indicate that 17−4PH stainless steel is particularly susceptible to crevice and pitting corrosion. Consequently, 17−4PH shows no pronounced corrosion sensitivity within 15 days of exposure, supporting its provisional use in marine couplings subject to short-term salt fog environments, with caution regarding crevice corrosion risks. 17−4PH is suitable for marine coupling fasteners when combined with passivation, crevice sealing, or design optimization to mitigate pitting and crevice corrosion. Overall, this study provides an experimental basis for the application of 17−4PH stainless steel in diaphragm couplings under high salt fog environments.

The primary purpose of this randomized controlled trial was to evaluate serum metal levels in patients after total hip arthroplasty (THA) with a conventional compared with a modular dual-mobility bearing. The secondary aim was to compare patient-reported outcome measure (PROM) scores between the 2 cohorts. Patients undergoing primary THA for osteoarthritis were randomized to receive either a modular dual-mobility or conventional polyethylene bearing. All patients received the same titanium acetabular and femoral components and a ceramic femoral head. Serum cobalt and chromium levels were measured preoperatively and annually at 1 through 5 years postoperatively. A total of 53 patients were enrolled. The 2 cohorts did not differ significantly in terms of demographics. In the conventional-bearing cohort, 76% of the patients were White and 24% were Black, African American; 48% of the patients were male and 52% were female. In the dual-mobility cohort, 86% of the patients were White and 14% were Black, African American; 79% of the patients were male and 21% were female. Forty-one patients who were randomized to a modular dual-mobility (n = 24) or conventional (n = 17) bearing and had a minimum follow-up of 2 years underwent serum metal analysis. No differences in serum cobalt levels (mean, 0.14 ng/mL [range, 0.075 to 0.29 ng/mL] versus 0.21 ng/mL [range, 0.075 to 0.57 ng/mL]; p = 0.22) or chromium levels (mean, 0.14 ng/mL [range, 0.05 to 0.50 ng/mL] versus 0.12 ng/mL [range, 0.05 to 0.35 ng/mL]; p = 0.65) were identified between the modular dual-mobility and conventional cohorts, respectively, at the 2-year postoperative time point. There were no significant differences in serum cobalt or chromium levels at 1 and 2 years postoperatively in patients who received a ceramic femoral head and this specific dual-mobility bearing compared with a ceramic head and a conventional acetabular component. While modest expected elevations in postoperative relative to preoperative serum cobalt and chromium levels were observed in the dual-mobility group, in no case did the cobalt level exceed the laboratory reference range or the threshold of 1 ng/mL that has been associated with adverse local tissue reactions due to mechanically assisted crevice corrosion. Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.

ABSTRACT Aiming at the tubing string fracture problem in an ultra-deep well, this paper systematically elaborates on the failure mechanism of the well’s tubing string through experimental tests and mechanical simulations, based on the downhole environment and tubing string parameters. Test results show that the hardness, metallographic structure, and tensile properties of the failed tubing string all meet the requirements; the weight percentages of oxygen and iron in the outer wall, thread root, and fracture surface areas of the failed tubing string all exceed 30%, and the weight percentage of chloride ions in the corrosion products is 10.71%; mechanical simulation indicates that the maximum stress at the tubing fracture reaches 1362.6 MPa, which is far higher than the theoretical residual strength. The final conclusion on the cause of tubing string failure is drawn as follows: under the conditions of high chloride ion concentration and dissolved oxygen, the tubing string undergoes crevice corrosion, and stress concentration induces stress corrosion cracking, ultimately leading to the tubing string fracture. This study provides a basis for the optimized design of tubing strings under similar well conditions.

Stainless steel flange assemblies on an offshore platform experienced crevice corrosion after the bolting was switched from galvanized steel to 25Cr (chromium) super-duplex. Crevice corrosion initiated from the external marine atmosphere, which led to suspicions that the zinc coating on the galvanized bolting was responsible for the many decades of crevice corrosion prevention. Using sea salt layers to simulate marine conditions, electrochemical-based tests were conducted to explore whether zinc could galvanically protect nearby stainless components. Overall, it was demonstrated that zinc/galvanized materials can provide effective polarization protection under relatively dry salt film conditions.