Improved Corrosion Protection Research Articles

Superhydrophobic zinc oxide/epoxy coating prepared by a one-step approach for corrosion protection of carbon steel

Corrosion in carbon steel (CS) has been an existing issue and it calls attention to the need for improved corrosion protection. At present, superhydrophobic (SHB) coating technology has piqued the interest of researchers as alternative means of mitigating metal corrosion. Herein, a one-step solution deposition process was used to prepare an SHB coating based on nano-zinc oxide/epoxy (ZnO/EP) on CS and its corrosion resistance performance was analyzed by the means of electrochemical analysis and compared with that of the blank CS metal and the regular coatings (plain EP and regular ZnO/EP). Results implied the as-prepared SHB coating shows remarkable improvement in corrosion protection for the substrate. Notably, it exhibited higher in both impedance modulus (|Z|) and coating resistance (Rc) results approaching 1010 Ωcm2, than those of regular coatings by 3 orders of magnitude to that of plain EP (∼107 Ω cm2), and 1 order of magnitude to regular coating (∼109 Ω cm2), indicating its superior corrosion resistance performance. Besides that, the superior inhibitive effect of the SHB ZnO/EP (ZES) is also proven by the potentiodynamic polarization (PDP) results, in which the Icorr value is suppressed down to 2.08 × 10−11 A/cm2, thereby achieving an excellent corrosion rate result of 3.38 × 10−11 mm/year. The exceptional barrier protection is ascribed to the presence of a stabilized air interlayer captured within the coating/electrolyte interface thus effectively blocking the penetration of electrolyte into the coating. This facile yet effective one-step processed SHB coating offers an effective route to improve the corrosion resistance performance of the CS metal and thereafter expand its potential applications.

Eco-Friendly Approach for the Construction of Superhydrophobic Coating on Stainless Steel Metal Based on Biological Metal-Organic Framework and Its Corrosion Resistance Performance.

In this paper, we present a sustainable approach for the creation of superhydrophobic (SP) coating on a stainless-steel substrate based on a biological metal-organic framework (MOF). The MOF was synthesized using aspartic acid as a linker and copper ions as a core metal. Two SP coatings were well constructed on stainless steel utilizing electrodeposition of nickel (Ni) and nickel altered by MOF (Ni@Bio-MOF) coatings followed by soaking in a solution of stearic acid in ethanol. The results of Fourier transform infrared spectroscopy demonstrate that the stearic acid-grafted nickel coating (Ni@SA) and the stearic acid-grafted Ni@Bio-MOF composite (Ni@Bio-MOF@SA), were effectively deposited on the stainless steel. The wettability findings displayed that the water contact angle of Ni@SA and Ni@Cu-As MOF@SA are 160° ± 1.1°, and 168° ± 1.2°, respectively. The prepared SP coating was also found to be chemically and mechanically stable. The results show that the Ni@SA coating maintains SP characteristics in a pH range of 3-11 while the Ni@Cu-As MOF@SA coating retained SP characteristics in a pH range of 1-13. Additionally, the superhydrophobic Ni@SA coating demonstrated SP characteristics up to a length of abrasion equal to 1300 mm, while the Ni@Cu-As MOF@SA coating exhibited SP characteristics up to a length of abrasion equal to 2700 mm. Furthermore, the Ni@SA and Ni@Cu-As MOF@SA coatings exhibited significantly improved corrosion protection in a 0.5 M NaCl solution compared with bare stainless steel, with protection efficiencies of approximately 94% and 99%, respectively. The results of this study demonstrate that the proposed approach is a promising method for the fabrication of eco-friendly and corrosion-resistant SP coatings on stainless steel substrate.

Electrode Potential-Dependent Studies of Protein Adsorption on Ti6Al4V Alloy.

This article presents the potential-dependent adsorption of two proteins, bovine serum albumin (BSA) and lysozyme (LYZ), on Ti6Al4V alloy at pH 7.4 and 37 °C. The adsorption process was studied on an electropolished alloy under cathodic and anodic overpotentials, compared to the open circuit potential (OCP). To analyze the adsorption process, various complementary interface analytical techniques were employed, including PM-IRRAS (polarization-modulation infrared reflection-absorption spectroscopy), AFM (atomic force microscopy), XPS (X-ray photoelectron spectroscopy), and E-QCM (electrochemical quartz crystal microbalance) measurements. The polarization experiments were conducted within a potential range where charging of the electric double layer dominates, and Faradaic currents can be disregarded. The findings highlight the significant influence of the interfacial charge distribution on the adsorption of BSA and LYZ onto the alloy surface. Furthermore, electrochemical analysis of the protein layers formed under applied overpotentials demonstrated improved corrosion protection properties. These studies provide valuable insights into protein adsorption on titanium alloys under physiological conditions, characterized by varying potentials of the passive alloy.

Effect of sodium dodecyl sulfate surfactant on the surface properties of electroless NiP-TiO2-ZrO2 composite coatings on magnesium AZ91D substrate

This research incorporated nano TiO2 and ZrO2 particles into the NiP electroless bath to produce NiP-TiO2-ZrO2 composite deposits on magnesium AZ91D substrates. The impact of sodium dodecyl sulfate (SDS) (anionic surfactant) was utilized for deposition to minimize the agglomeration and clustering of particles in the electroless bath. Surface properties such as atomic force microscopy, energy dispersive X-Ray analysis, scanning electron microscopy, and X-ray diffraction are used to evaluate the surface morphologies of coating, surface roughness, elementary composition, and crystalline structure of the deposits. Furthermore, the impact of SDS surfactant on the corrosion properties of deposits was also studied using potentiodynamic polarization in a 5 wt% NaCl solution. The overall results reveal that incorporating anionic surfactant SDS at the optimum concentration of 1.5 g/L (CMC value) improved wettability, deposition rate, and surface roughness compared to the deposits developed without surfactant. The proposed mechanism is that the molecules of SDS surfactant could come into contact with the surface of NiP-TiO2-ZrO2 composite coating in the bath, increasing nanoparticle dispersion and resulting in a uniform coating. Furthermore, the electrochemical results show improved corrosion protection efficiency (PE%) of NiP-TiO2-ZrO2 composite coatings by increasing the concentration of SDS surfactant, achieving ∼87.9% at (1.5 g/L) CMC value.

INVESTIGATION OF MODERN NANO-COMPOSITE COATINGS USED IN PASSIVE CORROSION OF METAL STRUCTURES

Corrosion caused by the interaction of metal with the environment is one of the biggest problems affecting the country's economy. One of the easiest ways to prevent corrosion is to cover metals with paint, plastic, or wood. Several types of coatings based mainly on electrochemical principles have been adopted by corrosion scientists to prevent corrosion. Fortunately, four types of coatings are used in different ways in the metal and metallurgical industry, based on cost and effectiveness. One of the cheapest and most effective ways to prevent corrosion is to use barrier coatings such as plastic, powder, and paint. Thus, nanocomposite coatings by electrochemical deposition offer excellent scratch and corrosion resistance on metal surfaces. These coatings can be used to restore components instead of replacing them, resulting in reduced maintenance costs and inconvenience. Significant improvements in corrosion protection of steel have been reported using metal-metal matrix, metal-metal oxide matrix, metal-polymer matrix and ceramic-metal matrix nanocomposite. This review provides an overview of the work on nanocomposite coatings and re-evaluates the literature for further research in this still unproven field. Keywords: Metal Structures, passive corrosions, nano-containing coatings, polymerization, Nanotechnology

Enhanced protection of manganese-doped zinc molybdate with synergistic corrosion resistance effects

Zinc molybdate (ZM) materials modified with different elements have a variety of properties, and therefore the study of metal elements modification for improvement in corrosion protection of ZM can be meaningful in practical applications. Herein, the manganese-doped zinc molybdate (Mn-ZM) material with synergistic anticorrosion effects was prepared through a one-step hydrothermal method. The total impedance value of Mn-ZM coating has increased by 341.6 % and 415.2 % in comparison with that of the ZM coating and pure epoxy coating after immersion in 3.5 wt% NaCl solution for 72 h, showing the best corrosion protection performance. The synergistic corrosion protection effects of Mn-ZM material were based on the multiplayer passive films, the permeation retarding effect and the improvement of hydrophobic and dispersion properties, which could cooperate with each other to delay the electrochemical corrosion processes. Herein, this work provides a new reference for the further study in elemental doping modification of other inorganic anticorrosion materials in applications.

Developing levodopa-modified sol-gel coating with enhanced anticorrosion performance on Mg alloy AZ31

PurposeThis study aims to develop a sol-gel-based coating to provide a long-lasting corrosion protection on AZ31 Mg alloy. Silane-based sol-gel coatings have been successfully applied to Mg alloys for corrosion protection. However, the micro or nano defects formed during condensation and solidification will cause the coating failure during a long-lasting immersion in a saline solution. More durable corrosion-protective sol-gel coatings are needed.Design/methodology/approachA sol-gel-based coating was modified on AZ31 Mg alloy by levodopa (DOPA). The long-lasting corrosion protection mechanism was studied by multiple electrochemical testing methods and surface characterization techniques.FindingsLong-term testing by electrochemical impedance spectroscopy in aqueous 0.1 M NaCl indicated that the modified DOPA@sol-gel coating exhibited significant corrosion protection performance (>14 days). In comparison, the DOPA-free sol-gel coating failed only after three days of testing. The improved corrosion protection is attributed to the self-polymerized DOPA filling to the micro or nano defects in the glassy cross-linked networks of the sol-gel coating, which greatly improves the compactness of the coating.Originality/valueThe method of this study is simple and easy to process, the raw materials are green and the protective effect is excellent, which is of significance for the study of magnesium alloy corrosion protection.

Mechanical Study of Aluminium -Silicon Carbide -Tungsten Carbide Hybrid Composite Synthesized Through Powder Metallurgy Technique

In this study, powder metallurgy is used to create hybrid metal matrix alloys made of aluminium-silicon carbide -tungsten carbide. Aluminium metal matrix composites are now vastly used in automobile industry due to superior qualities, such as improved corrosion protection, high ductility, and strength to weight ratio is also high too. With individual silicon carbide reinforcement, weight percentages of 5%, 10%, 15% and 20% of composite samples are created using the powder metallurgy method. The manufactured composite samples' physical and mechanical characteristics were examined. By using two analysis(SEM and XRD), aluminium, siliconcarbide, and tungsten carbide are found. Aluminium -10%Silicon Carbide -10%Tungsten Carbide reinforcement was determined to have a higher ultimate tensile strength (UTS) of 263 MPa as well as yield strength (YS) of 202 MPa for composite. Aluminium -10%Silicon Carbide -15 %Tungsten Carbideand Aluminium -10%Silicon Carbide -20%Tungsten Carbide reinforcement showed that the intermetallic specimenis formed(eg: Al2Cu), which causes a drop in the UTS and YS of manufactured samples. Hybrid composites made of Aluminium, silicon carbide10%, and 10% WC had the greatest combination of mechanical properties. Aluminium, silicon carbide, and WC particles can be seen in the XRD images. Aluminium-silicon carbide 10%-15% WC and aluminium-silicon carbide 10%-20% WC were found to have intermetallic phases present as well. SEM as well as EDS mapping were verified, reinforcements for the 15% and 20% WC reinforcements were distributed uniformly and formed into agglomerations. In comparison to monolithic aluminium, the results revealed that the aluminium-silicon carbide 10%- 10% WC has superior mechanical properties.

Dopamine self-polymerized sol-gel coating for corrosion protection of AZ31 Mg Alloy

Mg alloys have excellent mechanical and physical properties. Unfortunately, the poor corrosion resistance becomes the main disadvantage of the application of such materials in aqueous and atmospheric media. Although the sol-gel-based coating has attracted significant attention for alloys in corrosion protection, most of the existing sol-gel coatings are unable to give a long-term protection for the substrate against corrosion in saline solutions due to micro-/ nano-pores contained in its glassy sol-gel networks. To address this issue, a new sol-gel coating was prepared by utilizing the strong adhesion property of polydopamine (PDA) to provide a highly condensed sol-gel-based coating (PDA@sol-gel) on Mg alloy AZ31. Long-term corrosion testing by electrochemical impedance spectroscopy in aqueous 0.1 M NaCl indicated that the prepared PDA@sol-gel coating exhibited a substantially improved corrosion protection performance with a test duration of over 20 days. In comparison, the unmodified coating failed after 3 days of immersion in aqueous NaCl. The improved anti-corrosion performance may be attributed to the self-polymerized PDA filling the micro-/ nano defects in the cross-linked network of the SiO2 sol-gel, which greatly improves the compactness of the coating. This work presented a new approach to significantly improve the corrosion protection performance of magnesium alloys by dopamine-modified sol-gel coating, which can find ample applications in a wide range of industries.

Electropolymerized polypyrrole silver nanocomposite coatings on porous Ti substrates with enhanced corrosion and antibacterial behavior for biomedical applications

This work proposes an innovative strategy that combines two well-known easy and economical preparation techniques: powder metallurgy based space-holder (SH) technique to provide porous biocompatible Ti substrates with balanced biomechanical behavior (for cortical bone tissue substitution) promoting bone ingrowth and biocoating infiltration, and electropolymerization to coat these substrates with the polypyrrole–silver nanoparticles (PPy-AgNPs) composite conductive polymers improving its corrosion resistance, biocompatibility with enhanced antibacterial activity. The deposited PPy-based coatings present a cauliflower-like structure well adhered to the porous substrates. The macroporosity of and rough inner pore surface of Ti SH substrates are responsible for the superior adhesion of the conductive polymer comparing to typical denser substrates obtained by powder metallurgy or forging. The corrosion protection properties of the coatings were investigated by open circuit potential and Anodic Polarization in PBS media to simulate possible implant conditions, revealing improved corrosion resistance for the composite coatings. The bioactivity of the coatings was evaluated by immersion tests, revealing the formation of Hydroxyapatite after 90-day immersion in PBS. In both PPy and PPy-AgNPs composite coatings, a displacement of the polarization curves to more noble potentials and a decrease in the current density, indicated that the coating's protective character is maintained after 90-day immersion in PBS. The antibacterial activity was assessed by using the Kirby–Bauer disk-diffusion method against Staphylococcus aureus (ATCC 25923). The inhibition halo increased from 5.5 ± 0.4 mm for the bare substrate to 8.2 ± 0.6 mm for the PPy-coated substrate and to 12.5 ± 0.7 mm for the PPy-AgNPs-coated porous Ti. This feature associated to the improved corrosion protection and biocompatibility would significantly contribute to the success of the potential use of porous Ti implants by SH technique envisaging substitution of small damaged bone tissues for example in tumors.

Corrosion Protection Evaluation of Copper Coated with a Block Copolymer and Block Coploymer/Carbon Black Nanoparticles in 3 wt% NaCl Solution

AbstractThis paper presents a successful preparation of SEBS (a copolymer polystyrene‐block‐poly (ethylene‐ran‐butylene)‐block‐polystyrene) and SEBS‐CB (SEBS‐Carbon Black nanoparticles) coatings on a copper surface following a well‐defined immersion protocol. Such coatings′ protection capacity was tested in a 3 wt% NaCl medium using potentiodynamic polarization, cyclic voltammetry (CV), and electrochemical impedance techniques (EIS). The electrochemical measurements indicate that SEBS and SEBS‐CB are cathodic‐type inhibitors mainly hindering the diffusion of oxygen molecules toward the copper substrate. It also indicates the decrease in chloride ion attack on the coated copper layer. Not only that, but it also affirms the decrease in ‘s transport to the bulk solution, resulting in our sample being further protected at more positive potential. Cu‐SEBS‐CB electrodes showed a slight improvement in corrosion protection compared to Cu‐SEBS electrodes. π‐π stacking was associated with improving the performance of these coatings. The keys functions of incorporating CB are improving the electrode conductivity and having a denser and more compact coating than that without CB. The order of inhibition efficiency obtained by potentiodynamic polarization is in good agreement with the results achieved by electrochemical impedance spectroscopy. Also, the inhibition efficiency of Cu‐SEBS and Cu‐SEBS‐CB increases with increasing the ratio of SEBS. Adsorption of SEBS and SEBS‐CB on copper surface follows the Langmuir isotherm.

Effects of poly(o-phenylenediamine) functionalized SiC on the corrosion protection ability of neat polyurethane coating system in the marine environment

A novel nanocomposite consisting of polyurethane (PU), poly(o-phenylenediamine) (PoPD), and silicon carbide (SiC) nanoparticles was investigated for its application in marine environment through electrochemical techniques. The PoPD/SiC nanofillers were characterized by TGA, XRD, SEM/EDX, and TEM analyses. The anticorrosion and mechanical properties of different coating formulation in marine environment were evaluated by electrochemical impedance spectroscopy (EIS) and scanning electrochemical microscopy (SECM). It was also found that the coating resistance of PU-PoPD/SiC nanocomposite was over 41 times higher than that of the PU coating. The PU-PoPD/SiC coatings on the brass showed low current of 1.9 I/nA due to copper dissolution and 6.8 I/nA due to zinc dissolution because of the well distribution of PoPD/SiC nanofiller in PU coating. The analyses of the resultant degradation products by SEM/EDX and XRD techniques confirmed the presence of Si which has a major role in protecting the brass surface against corrosion. Results showed that the PU composite with 2 wt.% PoPD/SiC hybrid nanofillers had outstanding coating performance. This nanocomposite demonstrated improved corrosion protection. As a result, the developed PU-PoPD/SiC nanocomposite has exceptional adhesion strength and anticorrosion properties and might be exploited to develop next-generation anticorrosive coatings.

Self-healing epoxy composite coating based on polypyrrole@MOF nanoparticles for the long-efficiency corrosion protection on steels

In this work, a simple strategy was applied to modify zeolitic imidazolate framework-8 (ZIF-8) by the conductive polypyrrole (PPy) through in-situ polymerization. The synthesized PPy@ZIF-8 composite material as an active filler has been added into epoxy resin (EP) to produce a long-term anti-corrosion coating. The corrosion resistance of PPy@ZIF-8/EP coating was evaluated by electrochemical impedance spectroscopy (EIS) test and salt-spray test. The results showed that the introduction of the filler significantly improved the anti-corrosion performance of EP. After 30-day immersion in 3.5 wt% NaCl solution, the PPy@ZIF-8/EP coating showed a high impedance modulus of |Z|0.01 Hz (3.7 × 108 Ω cm2), which was four orders of magnitude higher than the neat EP. The improvement in corrosion protection could be attributed to the synergistic combination of passive and active corrosion resistance mechanisms. The PPy@ZIF-8 particles could not only be used as a passive nanofiller against corrosion media but also display a self-healing behavior due to the formation of the passivation iron oxide and Zn(OH)2 deposition layer on the steel substrate by electrochemical reactions, after the corrosion media reached the metal. This study provides new insight into the development of multifunctional anti-corrosion coatings for engineering applications.

Electrodeposition of Cu-Reinforced Polyaniline Coating for Protection of AH36 Steel in Natural Seawater

The marine environment is highly corrosive for mild and low alloy steels. This study aimed to enhance the corrosion resistance of the AH36 steel in a saline medium by coating it with a copper particles reinforced polyaniline (PANI) layer. PANI and Cu particles were grown on the steel surface by electrodepositing methods. Firstly, PANI was electropolymerized in the presence of oxalic acid, followed by the electrodeposition of Cu particles at different deposition times. The coating showed a well-distribution of Cu particles in the polymer matrix and excellent adhesion. Furthermore, the Cu particles and PANI-coated steels exhibited corrosion resistance significantly in the saline medium compared to the bare substrate and pristine PANI-coated samples. The improved corrosion protection of a Cu@PANI coating on the AH36 steel could contribute to forming a physical barrier by filling Cu particles on the PANI pores.

Fabrication of 8-hydroxyquinoline loaded in an aluminum-based metal-organic framework for strengthening anti-corrosion behavior of silane primer coating

In this article, MIL-53as(Al) metal-organic framework (MOF) was synthesized and loaded with 8-hydroxyquinoline (8HQ) as a corrosion inhibitor. The characterization based on FTIR, Raman, XRD, and XPS confirmed the successful loading of 8HQ in MOF. The corrosion inhibitive activity of the products was studied in the solution phase, single silane coating, and duplex coating system consisting of hybrid silane primer and epoxy topcoat applied on galvanized steel. XPS confirmed chemisorption of released 8HQ from the MIL-53as(Al) on the metal surface. Electrochemical test results revealed a significant improvement in corrosion protection of single layer and duplex coating systems in the presence of 8HQ-doped MOF.

Enhancement of the corrosion resistance of mild steel with femtosecond laser- nanostructuring and CrCoNi medium entropy alloy coating

In this work, the corrosion resistance of mild steel surface nanostructured with a femtosecond laser and coated with high corrosion resistant CrCoNi (CCN) medium entropy alloy through magnetron sputtering is studied. Substantial improvement in corrosion protection was achieved by applying a combination of high-power femtosecond laser surface nano-structuring at ambient conditions and thin-film coating with (CCN) medium entropy alloy. XRD analysis revealed that femtosecond laser structuring increases the susceptibility of the surfaces to Fe2O3 nucleation through oxidation. The surface wettability measurements and electrochemical polarization tests revealed that the combined approach of femtosecond laser structuring and magnetron sputter coating is the best for desired high corrosion resistance. Through this novel method, the resulting corrosion resistance of mild steel was improved by more than one-fold. The results are explained considering the detailed microstructural analysis. The presented findings open new possibilities for corrosion prevention using a combination of new powerful technologies that yield to unprecedented corrosion-inhibition efficacy.

Polymer-Based Nanocomposite Coating Methods: A Review

Coating technology is widely recognized as the most cost-effective and efficient method of preventing metal corrosion. Polymers have been regarded as a powerful coating material owing to their excellent barrier qualities, simplicity of modification, and large-scale production. Nanomaterials differ significantly from their physical and chemical properties, and have been hailed as highly promising functional materials in a wide range of applications, affecting nearly every aspect of science and technology. The addition of organic or inorganic nanofiller particles to polymer nanocomposite coatings may improve corrosion protection and lower the possibility of blistering or delamination. High hardness for polymer coatings, on the other hand, could be achieved by forming hard nanocrystalline phases inside the matrix. This article provides an overview of recent developments in polymer nanocomposite coatings in terms of their history, coating methods, properties, features, and drawbacks.

INVESTIGATION OF THE EFFECT OF MULTI-LAYER COATING ON CORROSION PREVENTION PERFORMANCE FORMED BY THE APPLICATION OF SOLVENT-BASED ZINC LAMEL COATING ON ALKALI ZINC AND ALLOY ZINC COATING

Bu çalışmada, alkali çinko, çinko-nikel ve çinko-demir alaşım kaplama prosesleri ile çözücü bazlı çinko lamelli kaplama prosesi yeniden düzenlenerek bir araya getirilmiş ve iki farklı kaplama prosesinin tekil üstün özellikleri birleştirilerek üstün korozyon önleme performansına sahip ürünlerin üretilmesine olanak sağlayan yeni bir proses geliştirilmiştir. Yürütülen deneysel çalışmalar sonucunda elde edilen ve görsel uygunluk kriterini sağlayan kaplamalar kuru yapışma, su direnci, nem direnci, tuz sisi, çevrimsel korozyon ve kimyasal direnç testlerine tabi tutulmuştur. Geliştirilen yeni proses, yüksek korozyon direncine (>1000 saat tuz sis testi ve >63 döngü döngüsel korozyon testi), yüksek sıcaklık direncine (300 °C'de bir saat), kimyasal dirence ve elektriksel yalıtkanlığa sahip parçaların üretilmesini olanak sağlamıştır. Testlerden elde edilen sonuçlar otomotiv endüstrisinin beklentileriyle kıyaslanmış ve beklentilerden daha üstün özellikler elde edilmiştir.

The role of acetylacetone in alkaline surface modification bath of electro-galvanized steel to enhance protective functioning of a hybrid silane coating

The current work outlines the impact of acetylacetone (AcAc) in the alkaline surface treatment bath on durability and the anti-corrosion properties of electro-galvanized steel (EGS) coated with a hybrid silane composition. The surface characteristics of the EGS samples before and after modifications were appraised using atomic force microscopy, field emission scanning electron microscopy, and contact angle measurements confirming the changes in roughness, morphology and wettability properties imposed by surface treatments. To elucidate the chemical composition of the protecting layer developed on the surface of EGS, X-ray photoelectron spectroscopy was utilized which evidently endorsed forming a film consisting of zinc hydroxide, zinc oxide, and zinc acetylacetonate. The corrosion resistance of the specimens during immersion in 3.5 % NaCl medium was determined using electrochemical impedance spectroscopy and polarization experiments. The low-frequency impedance (at 0.01 Hz) of silane-coated samples modified in the optimal condition (0.5 M NaOH bath) in the presence and absence of AcAc was respectively ca. 15,900, 5800 Ω·cm2. The electrochemical results corroborated the overriding role of a trace amount of AcAc in the corrosion protection of silane-coated EGS samples. The novel surface treatment proposed in this work provides improved corrosion protection of silane coating on EGS having the lowest icorr and presenting inhibition efficiency of 74 % in polarization experiment.

Polyphthalocyanine coatings for corrosion protection on additive manufactured steel materials

Polyphthalocyanine polymer films are deposited on additive manufactured (AM) 316L steel samples for corrosion protection. Coatings were deposited on the metallic surface using a drop casting method and then set via thermal polymerization of tetracyanobenzene to produce polyphthalocyanine. The formation of the polymer film on the metal surface was confirmed by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The coated AM steel had a more positive corrosion potential compared to the uncoated sample indicating improved corrosion protection. XPS studies probed the bonding properties between the coating and additive manufactured metal surface. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) studies confirm the corrosion protection ability of the polyphthalocyanine films on AM samples in 3.5 wt% NaCl medium.