Journal articles: 'Metallic coatings; Corrosion protection'

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Kamachi Mudali, U., Sublime Ningshen, and A. Ravi Shankar. "Nanostructured coatings for corrosion protection in reprocessing plants." Pure and Applied Chemistry 83, no. 11 (August 18, 2011): 2079–87. http://dx.doi.org/10.1351/pac-con-11-02-08.

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The main process medium in the reprocessing industry is highly oxidizing nitric acid ranging from dilute to concentrated solutions containing fission products and from room temperature to boiling conditions. Corrosion resistance of materials chosen for reprocessing plants is of prime importance for uninterrupted operation. Surface modification and coatings can significantly improve the corrosion resistance of materials. A number of surface modification and coating development works such as double oxide coating on Ti for reconditioning (DOCTOR); mixed oxide coated Ti anodes (MOCTAs); nanostructured Ti, TiO2, TiN, and ZrN; bulk metallic glasses (BMGs); and superhydrophobic (SHB) coatings for corrosion protection are being pursued in our laboratory. Nanostructured coatings developed on Ti-like DOCTOR and MOCTAs showed improved corrosion resistance and longer life. Nanostructured Ti, TiO2, and ZrN coatings deposited on type 304L stainless steel (SS) by magnetron sputtering technique and Zr-based bulk metallic Zr59Ti3Cu20Al10Ni8 alloy deposited on type 304L SS by pulsed laser deposition (PLD) technique showed improved corrosion resistance in nitric acid. SHB coating on 9Cr-1Mo and Ti lead to improved corrosion resistance and biofouling resistance of Ti. The surface modification and coating development carried out in our laboratory for corrosion protection in reprocessing plants are briefly highlighted.

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Fürbeth, Wolfram. "Special Issue: Advanced Coatings for Corrosion Protection." Materials 13, no. 15 (August 1, 2020): 3401. http://dx.doi.org/10.3390/ma13153401.

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Corrosion is an important issue in many industrial fields. Among others, coatings are by far the most important technology for corrosion protection of metallic surfaces. The special issue “Advanced Coatings for Corrosion Protection” has been launched as a means to present recent developments on any type of advanced coatings for corrosion protection. Fifteen contributions have been collected on metallic, inorganic, polymeric and nanoparticle enhanced coatings providing corrosion protection as well as partly other functionalities.

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Alshmri, F. "Metallic Coatings: Al-Zn Alloys." Advanced Materials Research 915-916 (April 2014): 608–11. http://dx.doi.org/10.4028/www.scientific.net/amr.915-916.608.

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Steel sheet has one major drawback, it is attacked by moisture at low temperatures and oxygen at high temperatures. Fortunately, coatings can provide protection to steel sheet from corrosion. Aluminum and aluminum zinc coatings can be applied by different methods. These are chemical vapor deposition coating (CVD), slurry coating, vacuum coating, spray coating, cladding, electroplating, electrophoresis, diffusion coatings, cementation, calorizing and hot dipping. This paper aims at providing a survey of these processes.

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Tiwari, Abhishek, Saravanan Seman, Gaurav Singh, and Rengaswamy Jayaganthan. "Nanocrystalline Cermet Coatings for Erosion–Corrosion Protection." Coatings 9, no. 6 (June 20, 2019): 400. http://dx.doi.org/10.3390/coatings9060400.

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The processing techniques, microstructural characteristics, and erosion corrosion behaviour of Cr3C2–NiCr and tungsten carbide (WC)-based cermet coatings are reviewed in this work. Conventional and nanocrystalline Cr3C2–NiCr and WC-based cermet coatings are generally synthesized using thermal spray technique. The wear, erosion, and corrosion protection ability of conventional and nanocermet coatings are compared based on available literature. In Cr3C2–NiCr coatings, the corrosion resistance is offered by NiCr metal matrix while the wear resistance is provided by the carbide ceramic phase, making it suitable for erosion–corrosion protection. The nanocrystalline cermet coatings exhibits better erosion–corrosion resistance as compared to the conventional coatings. The nanocrystalline coatings reduces the erosion–corrosion rate significantly compared to conventional coatings. It is attributed to the presence of the protective NiCr metallic binder that allows easier and faster re-passivation when the coating is subjected to wear and the fine-grain structure with homogeneous distribution of the skeleton network of hard carbide phases. In addition, corrosion-accelerated erosion dominates the reaction mechanism of erosion–corrosion and, therefore, higher hardness, strength, and better wear resistance of nanocermet coating along with its faster repassivation kinetics accounts for improved corrosion resistance as compared to conventional coatings.

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Mardare, Laurentiu, Lidia Benea, Eliza Dănăilă, and Valentin Dumitraşcu. "Polymeric Coatings Used against Marine Corrosion of Naval Steel EN32." Key Engineering Materials 699 (July 2016): 71–79. http://dx.doi.org/10.4028/www.scientific.net/kem.699.71.

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The life time of the metallic materials exposed to marine environment is influenced by their corrosion resistance. The marine environment is considered to be very aggressive to metallic materials used in the marine industry. In order to protect metallic substrates against corrosion process, important efforts have been made to develop corrosion resistance coatings, besides the cathodic protection systems. Thus, during the last years there were developed a series of organic protective coatings that have as principal component one or more polymers. This paper present a comparative investigation regarding the corrosion resistance of: i) uncoated naval steel EN32, ii) coated naval steel EN32 with a two-component polymeric primer and iii) coated naval steel EN32 with two-component polymeric primer followed by epoxy polyurethane paint coating. All the samples have been subjected to corrosion in seawater collected from the Black Sea (Mangalia sea port). In situ electrochemical measurements as: open circuit potential (OCP), polarization resistance (Rp), potentiodynamic polarization (PD) and cyclic voltammetry polarization (CV) were performed to monitor the corrosion process. The results showed an improved corrosion resistance of polymeric coatings in marine environment compared with uncoated naval steel EN32

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Nawaz, Muddasir, Nazal Naeem, Ramazan Kahraman, M. F. Montemor, W. Haider, and R. A. Shakoor. "Effectiveness of Epoxy Coating Modified with Yttrium Oxide Loaded with Imidazole on the Corrosion Protection of Steel." Nanomaterials 11, no. 9 (September 3, 2021): 2291. http://dx.doi.org/10.3390/nano11092291.

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The search for highly effective corrosion protection solutions to avoid degradation of the metallic parts is enabling the development of polymeric organic coatings. Of particular relevance, polymeric nanocomposite coatings, modified with corrosion inhibitors, have been developed to provide enhanced surface protection. In this work, yttrium oxide nanoparticles loaded with corrosion inhibitor (Imidazole), used as additives in the formulation of epoxy for coated on the steel substrate. The loading of Y2O3 with imidazole was confirmed by field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and Brunauer–Emmett–Teller analysis. UV-Vis analysis demonstrated the pH-sensitive behavior of the imidazole that helps in self-release when necessary. Electrochemical impedance spectroscopy (EIS) of the coated samples revealed that the coating modified with Y2O3/IMD provides better corrosion protection compared to coatings containing only Y2O3. XPS analysis validated the presence of an imidazole protective film on the steel substrate that enhanced the corrosion resistance of the coated samples

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Figueira, Rita B. "Hybrid Sol–gel Coatings for Corrosion Mitigation: A Critical Review." Polymers 12, no. 3 (March 19, 2020): 689. http://dx.doi.org/10.3390/polym12030689.

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The corrosion process is a major source of metallic material degradation, particularly in aggressive environments, such as marine ones. Corrosion progression affects the service life of a given metallic structure, which may end in structural failure, leakage, product loss and environmental pollution linked to large financial costs. According to NACE, the annual cost of corrosion worldwide was estimated, in 2016, to be around 3%–4% of the world’s gross domestic product. Therefore, the use of methodologies for corrosion mitigation are extremely important. The approaches used can be passive or active. A passive approach is preventive and may be achieved by emplacing a barrier layer, such as a coating that hinders the contact of the metallic substrate with the aggressive environment. An active approach is generally employed when the corrosion is set in. That seeks to reduce the corrosion rate when the protective barrier is already damaged and the aggressive species (i.e., corrosive agents) are in contact with the metallic substrate. In this case, this is more a remediation methodology than a preventive action, such as the use of coatings. The sol-gel synthesis process, over the past few decades, gained remarkable importance in diverse areas of application. Sol–gel allows the combination of inorganic and organic materials in a single-phase and has led to the development of organic–inorganic hybrid (OIH) coatings for several applications, including for corrosion mitigation. This manuscript succinctly reviews the fundamentals of sol–gel concepts and the parameters that influence the processing techniques. The state-of-the-art of the OIH sol–gel coatings reported in the last few years for corrosion protection, are also assessed. Lastly, a brief perspective on the limitations, standing challenges and future perspectives of the field are critically discussed.

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Nie, X., X. Li, and Derek O. Northwood. "Corrosion Behavior of Metallic Materials in Ethanol-Gasoline Alternative Fuels." Materials Science Forum 546-549 (May 2007): 1093–100. http://dx.doi.org/10.4028/www.scientific.net/msf.546-549.1093.

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Corrosion performances of several metallic materials (Al6061 and Al319 alloys, 304 stainless steel and grey cast iron) in the ethanol-gasoline alternative fuels were investigated. Cyclic potentiodynamic polarization tests were used to study their corrosion behavior. Anodizing and plasma electrolytic oxidation (PEO) techniques were used to produce oxide coatings on the Al6061 and Al319 alloys, and the corrosion properties of these coatings in the alternative fuel environments were also evaluated. The results showed that, the 304 stainless steel, Al6061 and the coating materials are compatible with the alternative fuels. The oxide coatings on both Al alloys provided effective corrosion protection in the alternative fuel environments.

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Krivenko, Pavel, Sergii Guzii, and Hameedi Abdullah Jafar Al-Musaedi. "Atmospheric Corrosion Protection of Metallic Structures Using Geocements-Based Coatings." Solid State Phenomena 227 (January 2015): 239–42. http://dx.doi.org/10.4028/www.scientific.net/ssp.227.239.

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It is known that load-bearing metallic structures that are in service in the atmospheric conditions showed that are exposed to corrosion. The known-in-the art paint-and-lacquer protective coatings can provide protection of metal surfaces for a rather short period between 5 to 10 years. That is why these structures should be protected by the more advanced coatings of new generation, namely: geocement-based coatings which differ from the known-in-the-art binding materials by formation in the hydration products of the zeolite-like minerals and feldspathoids. The paper discusses substantiation of choice of geocement composition in the (хК, уna)2O⋅Al2O3⋅nSiO2⋅mH2O system, target synthesis of hydration products of the geocements matrix in the fields of dynamic cavitation, optimal parameters of cavitation treatment aimed at nanostructurization of the geocements matrix in order to synthesize zeolite-like and hydromicaceous phases, choice of appropriate hardening agents and fillers etc. for producing highly efficient protective coatings with high corrosion resistance, high adhesion to metallic substrate and durability.

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Shedam, M. R., S. S. Patil, Rakesh M. Shedam, and Shridhar N. Mathad. "Shielding of metals from the corrosion induced by water and humidity by using scratch resistant and hydrophobic silica coatings." Journal of Research in Physics 39, no. 1 (June 1, 2018): 23–30. http://dx.doi.org/10.2478/jrp-2018-0002.

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Abstract The objective of the present paper is to demonstrate the effect of sol-gel derived scratch resistant coatings on different metal surfaces for anticorrosive applications. However, practical applications are limited by problems intrinsic to sol-gel processing or specific of coating/metal systems. Coatings aimed to improve oxidation and wet corrosion resistance have been studied the most. The results published in the literature show that sol-gel coatings may offer good protection against oxidation. More difficult is to achieve a protection against wet corrosion. An important aspect of the application of the sol-gel method for coating metallic objects is also the deposition technique.

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Yang, Huan, Shi Qiu, Yu Feng Lu, Zhen Xing Liu, and Fei Lu. "Experimental Study on Corrosion Prevention of a Multilayer Coating System." Advanced Materials Research 881-883 (January 2014): 1307–11. http://dx.doi.org/10.4028/www.scientific.net/amr.881-883.1307.

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Aiming to the corrosion prevention of 16MnR steel surface in the light aggregate concrete, the paper applies a kind of corrosion prevention system composed of layered coating. It utilizes measurement methods such as field emission scanning electron microscopy and energy disperse spectroscopy to study the corrosion and change process of this kind of coating system in the surface of 16MnR steel in the environment of light aggregate concrete and make the evaluation on its effect of corrosion protection. The experiment result indicates that due to its mechanical masking function, the layered coating system can effectively restrain immersion of the corrosive medium in early corrosion period so as to protect the metallic matrix. With the deepening of the corrosion, the nanometer Zn particle has the function of cathodic protection on the metallic matrix, effectively enhancing the comprehensive corrosion protection ability of the coating system.

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Harada, Yoshio. "Corrosion Protection by Metallic Coatings and Its Practical Use." CORROSION ENGINEERING 37, no. 10 (1988): 618–25. http://dx.doi.org/10.3323/jcorr1974.37.10_618.

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Vakhitov, T. R., V. E. Katnov, P. V. Grishin, S. N. Stepin, and D. O. Grigoriev. "Biofriendly nanocomposite containers with inhibition properties for the protection of metallic surfaces." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 473, no. 2199 (March 2017): 20160827. http://dx.doi.org/10.1098/rspa.2016.0827.

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An attempt to combine two ‘green’ compounds in nanocomposite microcontainers in order to increase protection properties of waterborne acryl-styrene copolymer (ASC) coatings has been made. N -lauroylsarcosine (NLS) served as a corrosion inhibitor, and linseed oil (LO) as a carrier-forming component. LO is compatible with this copolymer and can impart to the coating self-healing properties. For the evaluation of the protective performance, three types of coatings were compared. In the first two, NLS was introduced in the coating formulation in the forms of free powder and micro-containers filled with LO, correspondingly. The last one was a standard ASC coating without inhibitor at all. Low-carbon steel substrates were coated by these formulations by spraying and subjected subsequently to the neutral salt spray test according to DIN ISO 9227. Results of these tests as well as the data obtained by electrochemical study suggest that such containers can be used for the improvement of adhesion of ASC-based coatings to the substrate and for the enhancement of their protective performance upon integrity damage, whereas the barrier properties of intact coatings were decreased.

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Papavinasam, S., B. Arsenault, M. Attard, and R. W. Revie. "Metallic Under-Layer Coating as Third Line of Protection of Underground Oil and Gas Pipelines from External Corrosion." Corrosion 68, no. 12 (July 11, 2012): 1146–53. http://dx.doi.org/10.5006/0566.

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This paper presents the concept of introducing a third line of defense in the form of a metallic under-layer coating—in addition to the traditional polymeric coating and applied cathodic protection (CP)—to protect the external surface of oil and gas pipelines. The three levels of protection would be the metallic under-layer coating, the polymeric top-layer coating, and the applied CP. This three-level system would be beneficial when the applied CP current is shielded from the pipeline by a dis-bonded polymeric coating, thermal insulator, or highly resistive soil. Two different combinations of metallic under-layer and polymeric top-layer coatings are presented to demonstrate this concept: 48%Zn and 52%Al under-layer with four different top-layer coatings: fusion-bonded epoxy (FBE), composite, urethane, and coal tar epoxy. Urethane top-layer coating with four different metallic under-layers: 48%Zn-52%Al, 85%Zn-15%Al, Al, and Zn. The criteria for the successful application of this concept also have been described.

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Calabrese, Luigi, Angela Caprì, and Edoardo Proverbio. "Anti-corrosion performances of hybrid silane coatings on AZ31 alloy." Anti-Corrosion Methods and Materials 65, no. 3 (May 8, 2018): 317–24. http://dx.doi.org/10.1108/acmm-01-2018-1891.

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Purpose This paper aims to evaluate the efficacy of a zeolite-filled silane sol–gel coating as protective layer on pretreated AZ31 magnesium alloy substrates. Design/methodology/approach Anti-corrosion properties of a silane–zeolite composite coating, at various zeolite content, have been investigated on AZ31 magnesium substrates subjected to different surface pretreatment procedures before coating deposition. A short time etching by hydrofluoric acid (HF) and an anodic polarization in NaOH solution were used as surface pretreatments. Findings High hydrophobicity and good adhesion performances of coatings have been observed. Corrosion protection performance, during immersion in 3.5 per cent NaCl solution, was evaluated by means of electrochemical impedance spectroscopy tests. All coating formulations evidenced good barrier properties. Better durability properties have been shown by coating obtained on HF pretreated magnesium substrate and with a 60 per cent of zeolite content. Originality/value High electrochemical reactivity of magnesium alloys represents the mayor limit of its application in many different fields. In this concern, zeolite-based coatings are emerging as potentially effective environmentally friendly coating for metallic substrates. Despite aluminum and stainless steel substrates, in the literature, only expensive direct synthesis zeolite coating was investigated for its application on magnesium alloys protection. For this reason, this paper fulfills the need to assess the adhesion and anti-corrosion behavior of sol–gel silane–zeolite coating in magnesium alloy substrates.

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Quddus, Abdul, Anwar Ul-Hamid, and Huseyin Saricimen. "Carburization behavior of high velocity oxy fuel sprayed metallic coatings at 900°C." Anti-Corrosion Methods and Materials 61, no. 6 (October 28, 2014): 436–44. http://dx.doi.org/10.1108/acmm-08-2013-1294.

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Purpose – The purpose of this investigation was to evaluate the performance of high velocity oxy fuel (HVOF) coated SS-310 samples in a carburizing environment. Design/methodology/approach – The carburization behavior of metallic coatings with three different compositions was studied under isothermal carburizing exposure conditions at 900°C for 125 hours. The coatings were deposited on SS 310 substrates using the HVOF technique. The ASTM Standard method was used to evaluate coating adhesion. Scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, X-ray diffraction and weight gain were used to evaluate the surface morphology, microchemical composition, phase constitution and degree of environmental protection imparted by the coatings. Findings – The experimental results indicate that Ni-rich coating offered better protection to SS 310 alloy compared to Co-rich coatings in carburizing environments. This was thought to be due to the formation of a continuous protective layer of Cr2O3 on the Ni-rich coating surface. Originality/value – The study has direct practical relevance to the petrochemical industry, particularly for refinery applications. In refinery service, SS310 is used in header damper plates. The useful service life of such header plates can be extended by the use of high temperature corrosion resistant metallic coatings. The present investigation highlighted the protection offered by Ni-based HVOF coated SS-310 samples in carburizing environment.

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Espitia-Cabrera, M. I., H. D. Orozco-Hernández, M. A. Espinosa-Medina, L. Martínez, and M. E. Contreras-García. "Comparative Study of Corrosion in Physiological Serum of Ceramic Coatings Applied on 316L Stainless Steel Substrate." Advanced Materials Research 68 (April 2009): 152–58. http://dx.doi.org/10.4028/www.scientific.net/amr.68.152.

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In recent years the use of ceramic coatings to reduce metallic corrosion has been greatly improved. It has been proved by several studies that coating of TiO2, ZrO2, SiO2, and other oxides or mixed oxides provide efficient protection against the corrosion of stainless steel in different media. In this work, alumina and zirconia films were obtained by electrophoretic deposition to investigate their use as protective coatings of 316L-Stainless steel for prostheses and dental implants. These were characterized by scanning electron microscopy (SEM), grazing incidence X-ray diffraction (GID), and atomic force microscopy (AFM). The corrosion behaviour in Hank’s solution at room temperature was studied using a potentiodynamic polarization technique. The electrochemical measurements showed a high corrosion resistance of 316L-SS coated by both types of ceramic film. The best behaviour was presented by the alumina coating. The morphologies of the corroded films showed that the alumina and zirconia films presented low damage with little pitting corrosion compared with the uncoated 316L-SS.

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Abdeen, Dana, Mohamad El Hachach, Muammer Koc, and Muataz Atieh. "A Review on the Corrosion Behaviour of Nanocoatings on Metallic Substrates." Materials 12, no. 2 (January 10, 2019): 210. http://dx.doi.org/10.3390/ma12020210.

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Growth in nanocoatings technology is moving towards implementing nanocoatings in many sectors of the industry due to their excellent abilities. Nanocoatings offer numerous advantages, including surface hardness, adhesive strength, long-term and/or high-temperature corrosion resistance, the enhancement of tribological properties, etc. In addition, nanocoatings can be applied in thinner and smoother thickness, which allows flexibility in equipment design, improved efficiency, lower fuel economy, lower carbon footprints, and lower maintenance and operating costs. Nanocoatings are utilised efficiently to reduce the effect of a corrosive environment. A nanocoating is a coating that either has constituents in the nanoscale, or is composed of layers that are less than 100 nm. The fine sizes of nanomaterials and the high density of their ground boundaries enable good adhesion and an excellent physical coverage of the coated surface. Yet, such fine properties might form active sites for corrosion attack. This paper reviews the corrosion behaviour of metallic, ceramic, and nanocomposite coatings on the surface of metallic substrates. It summarises the factors affecting the corrosion of these substrates, as well as the conditions where such coatings provided required protection.

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Wu, Tong Yu, David Arye, Philip E. Irving, Fang Ming Zhao, and Paul Jackson. "Fatigue Crack Development in Epoxy Coatings on Steel Substrate: The Role of Coating and Substrate Properties in Determination of the Onset of Fatigue Cracks." Advanced Materials Research 891-892 (March 2014): 854–59. http://dx.doi.org/10.4028/www.scientific.net/amr.891-892.854.

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Development of service cracks in epoxy based corrosion protective coatings limits the life of the substrate structure. If cracks develop, corrosion protection is lost and costs of repair and re-protection of large marine structures can be crippling. Factors controlling development of cracks in the coating are poorly understood, and predictions of coating lifetime approximate. For bulk tanker applications service strains imposed on coatings arise from both low frequency thermal mismatch strains and mechanical strains from wave action. In this work the number of cycles to crack initiation has been measured during strain controlled fatigue of two selected 300 μm thick coatings applied to a 5.5 mm thick steel substrate. Cycling was performed at frequencies of 1 Hz, and strain amplitudes between ±0.16% and ±0.5%. Coating crack development was monitored optically. It was found that cycles to crack initiation depended on both strain amplitude and on the static ductility of the coating. After initiation crack growth rates in the coating reduced with increasing surface crack length. The significance of the results is considered in the light of requirements for quantitative models for service life prediction of coatings on metallic substrates.

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Strachotová, K. C., M. Kouřil, K. Kuchťáková, and Š. Msallamová. "Inhibition efficiency of sodium salts of carboxylic acids on corrosion of lead in archive environment." Koroze a ochrana materialu 63, no. 1 (March 1, 2019): 37–47. http://dx.doi.org/10.2478/kom-2019-0005.

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Abstract Lead in archive environment suffers from severe corrosion attack caused by the organic acids’ vapours usually presented in such an environment. One of possible ways of corrosion protection of lead is its surface treatment by solutions of sodium salts of monocarboxylic acids (general formula CH3(CH2)n-2COONa, noted NaCn, n = 10, 11, 12). The principle of this corrosion protection is a creation of conversion coating on the lead’s surface, which decreases corrosion rate of lead in the atmospheric environment polluted by organic acids’ vapour. Our research aims at the selection of a suitable protection system that would be applicable to conservation of historical lead in archives and museums. This paper evaluates the corrosion behaviour of treated lead based on the values of polarisation resistance and shape of potentiodynamic curves in simulated corrosive environment (0.01 mol l−1 solution of acetic acid). The lead samples with different state of surface (pure, corroded and electrochemically cleaned) were treated with sodium salts of monocarboxylic acids NaCn (n = 10, 11, 12) having concentration of 0.01 and 0.05 mol l−1. In simulated corrosive atmosphere (above 0.001 mol l−1 acetic acid solution vapours), corrosion rate was measured by means of electrical resistance technique. The inhibition efficiency of monocarboxylic acids is dependent on their carbon chain length and their concentration. The greatest inhibiting efficiency in corrosive atmospheres and for all lead samples was observed for the sodium salt of dodecanoic acid having concentration of 0.05 mol l−1. Artificially created corrosion products and salt coatings were analysed by X-ray diffraction analysis and their surface morphology was observed by scanning electron microscopy. A protective salt coatings are mainly composed of metallic soaps in dimer form.

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Jurak, Thomas, Sina Jamali, Yue Zhao, Joe Williams, Abhishek Saxena, and Jason Hodges. "Novel Chromium-Free Technologies for the Prevention of Wet Stack Corrosion on Hot Dipped Metallic Coatings: A Review." Corrosion 74, no. 8 (March 31, 2018): 918–35. http://dx.doi.org/10.5006/2772.

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Advances in novel corrosion prevention technologies, including organic-inorganic hybrid sol-gel coatings, ultra violet radiation curable coatings, rare earth metal corrosion inhibitors, and other additions for the fabrication of smart coatings, and their potential application to hot dipped metallic coated steel strip products have been reviewed. Rather than exploring the prevention of atmospheric corrosion as in similar publications in the field, the authors have instead placed emphasis on the feasibility of the technologies for protection against “wet stack corrosion,” also known as wet storage staining. Such corrosion of hot dipped metallic coatings is a common problem in industry, but one rarely explored in academia.

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Abdalla, Khalid, Rahmat Azmi, and Aziz Azizan. "The Effect of pH on Zinc Phosphate Coating Morphology and its Corrosion Resistance on Mild Steel." Advanced Materials Research 626 (December 2012): 569–74. http://dx.doi.org/10.4028/www.scientific.net/amr.626.569.

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Zinc phosphate coating is commonly used for corrosion protection of metallic materials, mainly mild steel. In this study, influence of the pH of phosphating bath on the surface morphology and corrosion resistance of zinc phosphate coatings on mild steel was investigated. The phosphate layers were deposited on steel from phosphating bath at different pH values (1.75 ~ 2.75). The surface morphology and composition of phosphate coatings were investigated via scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX). The corrosion resistance of the coating was evaluated by polarization curves (anodic and cathodic) in an aerated 3.5% NaCl solution. The results showed that better surface coverage and corrosion resistance for the steel phosphated at pH 2.75.

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Nguyen-Tri, Phuong, Tuan Anh Nguyen, Pascal Carriere, and Cuong Ngo Xuan. "Nanocomposite Coatings: Preparation, Characterization, Properties, and Applications." International Journal of Corrosion 2018 (2018): 1–19. http://dx.doi.org/10.1155/2018/4749501.

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Incorporation of nanofillers into the organic coatings might enhance their barrier performance, by decreasing the porosity and zigzagging the diffusion path for deleterious species. Thus, the coatings containing nanofillers are expected to have significant barrier properties for corrosion protection and reduce the trend for the coating to blister or delaminate. On the other hand, high hardness could be obtained for metallic coatings by producing the hard nanocrystalline phases within a metallic matrix. This article presents a review on recent development of nanocomposite coatings, providing an overview of nanocomposite coatings in various aspects dealing with the classification, preparative method, the nanocomposite coating properties, and characterization methods. It covers potential applications in areas such as the anticorrosion, antiwear, superhydrophobic area, self-cleaning, antifouling/antibacterial area, and electronics. Finally, conclusion and future trends will be also reported.

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Healy, Bronach, Tian Yu, Daniele da Silva Alves, and Carmel B. Breslin. "Review of Recent Developments in the Formulation of Graphene-Based Coatings for the Corrosion Protection of Metals and Alloys." Corrosion and Materials Degradation 1, no. 3 (September 25, 2020): 296–327. http://dx.doi.org/10.3390/cmd1030015.

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Corrosion is a naturally occurring phenomenon and there is continuous interest in the development of new and more protective coatings or films that can be employed to prevent or minimise corrosion. In this review the corrosion protection afforded by two-dimensional graphene is described and discussed. Following a short introduction to corrosion, the application of graphene in the formulation of coatings and films is introduced. Initially, reduced graphene oxide (rGO) and metallic like graphene layers are reviewed, highlighting the issues with galvanic corrosion. Then the more successful graphene oxide (GO), functionalised GO and polymer grafted GO-modified coatings are introduced, where the functionalisation and grafting are tailored to optimise dispersion of graphene fillers. This is followed by rGO coupled with zinc rich coatings or conducting polymers, GO combined with sol-gels, layered double hydroxides or metal organic frameworks as protective coatings, where again the dispersion of the graphene sheets becomes important in the design of protective coatings. The role of graphene in the photocathodic protection of metals and alloys is briefly introduced, while graphene-like emerging materials, such as hexagonal boron nitride, h-BN, and graphitic carbon nitride, g-C3N4, are then highlighted.

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Huang, Wei, Di Li, Tian Liang Zheng, and Min Guo. "A Novel Anti-Corrosion Coating for Aluminium Alloy." Materials Science Forum 519-521 (July 2006): 723–28. http://dx.doi.org/10.4028/www.scientific.net/msf.519-521.723.

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A novel environmental protective water based metallic coating was developed for aluminum alloys, which mainly contains metal flake, silicate and silane. The coating's properties were investigated by neutral salt spray test, micro-hardness testing, adhesion test and electrochemical technique etc. Meanwhile the coating's surface and microstructure was observed by scanning electron microscopy (SEM). Furthermore, the film forming matter was examined by Fourier transform infrared spectroscopy (FTIR) test. Results showed that an excellent adhesive, heat-resisting, protective coating for aluminum alloy could be achieved by this technique. An interpenetrating polymer network (IPN) was formed in the coating by means of cross linking reaction of organosilicone and inorganic silicate. In thesis, the film forming mechanism and protection of coating were also discussed.

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dos Santos, Fábio C., Samarah V. Harb, Marie-Joëlle Menu, Viviane Turq, Sandra H. Pulcinelli, Celso V. Santilli, and Peter Hammer. "On the structure of high performance anticorrosive PMMA–siloxane–silica hybrid coatings." RSC Advances 5, no. 129 (2015): 106754–63. http://dx.doi.org/10.1039/c5ra20885h.

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Molina-Díaz, A., J. Delgado-Venegas, F. Juárez-López, G. Velázquez-García, and R. Cuenca-Álvarez. "Building of Protective Coating Against Corrosion by Flame Spraying of Mechanofused Composite Particles." MRS Proceedings 1765 (2015): 37–44. http://dx.doi.org/10.1557/opl.2015.804.

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ABSTRACTA protective coating was built and assessed in order to reduce the degradation of metallic substrates caused by corrosion damage. Hence, a set of coatings with different configurations, in terms of layer arrangement, was produced by flame-spraying of composite powder (AISI 316L stainless steel coated with an α-alumina layer) onto an AISI 1018 steel substrate. In order to ensure a homogeneous dispersion of phases, a correlation was established between the operating parameters of thermal spraying (roughness and surface temperature of substrate, spraying distance, passing speed) and the splat formation. Then, corrosion damage caused in the coated samples by exposure to a salt spray was monitored through weight measurements and observations with optical and scanning electron microscopy. The results show that corrosion still remains in all cases; however, it proceeds at lower rates for coatings made with composite particles plus an α-alumina layer. The weight loss due to corrosion damage was reduced in approximately 94% as compared with the substrate without protection. Coating adhesion was also improved by an increased substrate roughness, with no need for an intermediate layer.

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Syrek-Gerstenkorn, Berenika, Shiladitya Paul, and Alison J. Davenport. "Sacrificial Thermally Sprayed Aluminium Coatings for Marine Environments: A Review." Coatings 10, no. 3 (March 12, 2020): 267. http://dx.doi.org/10.3390/coatings10030267.

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One of the corrosion mitigation methods that is used for the protection of steel operating in seawater environments involves the application of sacrificial metallic coatings (such as aluminium, zinc, and their alloys). This paper reviews current knowledge about thermally-sprayed (TS) and cold-sprayed (CS) Al coatings for the corrosion protection of steel. It also summarises the key findings of the substantial amount of work that has been devoted to understanding mechanisms and the parameters that control the performance of TS Al coatings, such as the spraying method and its parameters like coating thickness and the application of sealer. The paper includes suggestions for areas of further research that could lead to the development of more resilient and longer-lasting coatings, based on the results from both laboratory and field tests that have been published in the literature. It also highlights the need for conducting simulated laboratory tests at conditions of intended service and the importance of long-term testing.

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Madhan Kumar, A., M. A. Hussein, Akeem Yusuf Adesina, Suresh Ramakrishna, and N. Al-Aqeeli. "Influence of surface treatment on PEDOT coatings: surface and electrochemical corrosion aspects of newly developed Ti alloy." RSC Advances 8, no. 34 (2018): 19181–95. http://dx.doi.org/10.1039/c8ra01718b.

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Ma, Yan Xuan, Ying Rui Zhang, Jia Tong Liu, Meng Yao Li, and Ya Qian Xu. "Self-Healing Epoxy Coating Modified by Double-Walled Microcapsules Based Polyurea for Metallic Protection." Key Engineering Materials 821 (September 2019): 313–20. http://dx.doi.org/10.4028/www.scientific.net/kem.821.313.

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The effectiveness of preploymer and 1,6-Hexamethylene diamine encapsulated by double-walled microcapsules based polyurea (PUA) was explored for healing the cracks generated in epoxy coatings. Double-walled microcapsules were systhesized by interfacial polymerization at the interface between the prepolymer droplets and the 1,6-Hexamethylene diamine droplets to form the polyurea shell. The effect of synthetic stirring speed on the morphology of the microcapsules was observed by scanning electronmicroscopy (SEM) and optical microscopy (OM). The chemical structure as well as the thermal properties and the core content were characterized by Fourier transform infrared spectroscopy (FTIR) and Thermogravimetric analyzer (TGA) respectively. Electrochemical impedance spectroscopy (EIS) studies of the artificial scratched area showed that the coating containing 2wt% and 5wt% microcapsules could effectively prevent further corrosion of the coating with high corrosion resistance efficiencies of 61.61% and 45.99% after immersing for 144h in seawater.

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Stankiewicz, Alicja, and Michael B. Barker. "Development of self-healing coatings for corrosion protection on metallic structures." Smart Materials and Structures 25, no. 8 (July 14, 2016): 084013. http://dx.doi.org/10.1088/0964-1726/25/8/084013.

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Sung, James C., and Ming Chi Kan. "The In-Situ Dressing of CMP Pad Conditioners with Novel Coating Protection." Materials Science Forum 534-536 (January 2007): 1133–36. http://dx.doi.org/10.4028/www.scientific.net/msf.534-536.1133.

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Kinik Company pioneered diamond pad conditioners protected by DLC barrier (DiaShield® Coating) back in 1999 (Sung & Lin, US Patent 6,368,198) and there has been no follower since then. Kinik's offered two varieties of DiaShield® Coatings: ultrahard tetrahedral amorphous carbon and superhard hydrogenated DLC. Kink also evaluated Cermet Composite Coating (CCC or C3, patent pending). C3 is unique that the coating composition grades from a metallic (e.g. stainless steel) under layer to a ceramic (e.g. Al2O3 or SiC) exterior. The metallic under layer can form metallurgical bond with metallic matrix on the diamond pad conditioner. The ceramic exterior is both wear and corrosion resistant. The gradational design of C3 coating will assure its strong adherence to the substrate because there is no weak boundary between coating and substrate. By dipping diamond pad conditioners of various designs in acidic solution (e.g. copper cleaning solution) for extended periods of time (e.g. 50 hours) the chemical inertness of various matrix materials are determined with the decreasing ranking as: hydrogenated DLC > C3 coating > tetrahedral amorphous carbon > sintered nichrome > brazed alloy > electroplated nickel.

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Liu, Z., H. Liu, F. Viejo, Z. Aburas, and M. Rakhes. "Laser-induced microstructural modification for corrosion protection." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 224, no. 5 (March 26, 2010): 1073–85. http://dx.doi.org/10.1243/09544062jmes1858.

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Laser surface modification of materials by melting and annealing has been the subject of considerable interest as a means of enhancing the corrosion performance of metallic alloys. Microstructural modification without changing surface chemical composition, in terms of homogenization/refinement of microstructures, dissolution/re-distribution of intermetallic particles, and extended solid solubility, resulting from rapid rates of cooling, provides the basis for property enhancement. This paper reviews authors’ work on laser surface melting (LSM) and laser annealing (LA) for the purpose of improved corrosion performance. Microstructural evolution and corrosion performance in a range of metallic alloys, followed by different treatments with different types of lasers, are presented. For LSM of aerospace aluminium alloys, the corrosion mechanisms of the laser-melted alloys have been discussed in the consideration of electrochemical characteristics of intermetallic particles with respect to the aluminium matrix and cooling rates leading to different degrees of refinement/removal of intermetallic particles. For LA of amorphous electroless Ni-W-P plating, porosity formation and grain growth and microstrain/residual stress resulting from laser-induced nanocrystallization are the major concerns, affecting corrosion performance. In addition, potential applications of LSM as pre-treatment method prior to conventional anodizing or post-treatment of thermal sprayed coatings have been demonstrated.

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Yabuki, Akihiro. "Self-Healing Coatings for Corrosion Inhibition of Metals." Modern Applied Science 9, no. 7 (July 1, 2015): 214. http://dx.doi.org/10.5539/mas.v9n7p214.

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Anti-corrosion protective coatings have been widely applied as a surface treatment to prevent corrosion ofvarious metallic materials, such as aluminum alloys, magnesium alloys, steel and zinc-coated steel, which areused in automobile parts, building structures, home appliances, etc. One of the most important characteristics ofthese coatings is the ability to self-heal. If a self-healing coating suffers mechanical damage and corrosivespecies in the environment begin to degrade the bare metal surface, the damaged surface is automaticallyrepaired by a chemical component of the coating. Chromate conversion coatings have self-healing properties.However, environmental concerns have necessitated the reduction and discontinuation of chromate-basedprotective coatings in recent years. This paper describes two recently developed self-healing coatings — afluorine polymer coating with metal particles and a coating comprised of particles and an organic healing agent.A fluorine polymer coating has self-healing properties, which are improved by the addition of metal particles. Aself-healing coating that uses particles and an organic healing agent has also been developed.

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Chaudhry, A. U., Vikas Mittal, M. I. Hashmi, and Brajendra Mishra. "Evaluation of Ni0.5Zn0.5Fe2O4 nanoparticles as anti-corrosion pigment in organic coatings for carbon steel." Anti-Corrosion Methods and Materials 64, no. 6 (November 6, 2017): 644–53. http://dx.doi.org/10.1108/acmm-10-2016-1725.

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Purpose Inorganic oxide addition can be synergistically beneficial in organic coatings if it can impart anti-corrosion properties and also act as an additive to enhance physical and/or chemical properties. The aim of this study was to evaluate the anti-corrosion benefits of nano nickel zinc ferrite (NZF) in the polymer film. Design/methodology/approach The time-dependent anti-corrosion ability of NZF (0.12-1.0 per cent w/w NZF/binder), applied on API 5L X-80 carbon steel, was characterized by electrochemical techniques such as open circuit potential, electrochemical impedance spectroscopy, linear polarization resistance and potentiodynamic. Characterization of corrosion layer was done by removing coatings after 216 h of immersion in 3.5 per cent w/v NaCl. Optical microscopy, field emission scanning electron microscopy and X-ray diffraction techniques were used to characterize the corroded surface. Findings Corrosion measurements confirm the electrochemical activity by metallic cations on the steel surface during corrosion process which results in improvement of anti-corrosion properties of steel. Moreover, surface techniques show compact corrosion layer coatings and presence of different metallic oxide phases for nanocomposite coatings. Originality/value The suggested protection mechanism was explained by the leaching and precipitation of metallic ion on the corroded surface which in turn slowed down the corrosion activity. Furthermore, improvement in barrier properties of rubber-based coatings was confirmed by the enhanced pore resistance. This work indicates that along with a wide range of applications of NZF, anti-corrosion properties can be taken as an addition.

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Aouici, Samia, El Hadi Boussaha, Ferial Krid, and Fadia Mechati. "Corrosion Resistance of Coatings Produced by Spraying Powders Under a Laser Beam in a Saline Environment NaCl 3% by the Electrochemical Method." Acta Universitatis Sapientiae, Electrical and Mechanical Engineering 12, no. 1 (December 1, 2020): 105–16. http://dx.doi.org/10.2478/auseme-2020-0008.

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Abstract The manuscript focuses on the study of corrosion resistance in NaCl medium of a 304L type stainless steel after application of protective nickel-based and cobalt-based coatings produced by powder spraying under a continuous CO2 laser (10.6 µm wavelength) beam. Using polarization and electrochemical impedance spectroscopy methods, the results found confirm that metallic coatings produced under high energy beams offer excellent protection up to an efficiency of E = 98.12% in aggressive environments with salinity to 3%.

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Toma, Alina Elena. "Coatings Innovations on the Inner Shell of Metal Grain Silos." Advanced Engineering Forum 21 (March 2017): 207–12. http://dx.doi.org/10.4028/www.scientific.net/aef.21.207.

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Some of the current research concerns the development of sustainability metallic silos study, highlights aspects of the treatment methods of the inner surface of the silos against the corrosive flow effects of granular material. By repeating the cycle of loading - unloading of granular material silo may lose bearing capacity due to the fatigue phenomenon. As a result, corrosion protection is required because of the silos can lead to a longer lifespan. Studies in this area aimed at finding new protection solutions, compatible with the granular material in store. In the field of metal silos, one of the innovative solutions, it consists of applying a protective coating on the inner wall layer made from ceramic powders and a composite material consisting of a resin reinforced with a specific curing agent. It is obtained such a protective steel with ceramic, applicable for walls silos, basic requirement consisting in achieve a interdiffusion physical, chemical or electrical between the two materials and the production of a minimum residual voltage at ceramic interface. The methodology for creating adhesion to metal-ceramic is described in this paper.

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Fathi, Ahlam M., Howida S. Mandour, and Hanaa K. Abd El-Hamid. "Corrosion Protection of Nano-biphasic Calcium Phosphate Coating on Titanium Substrate." Current Nanoscience 16, no. 5 (October 5, 2020): 779–92. http://dx.doi.org/10.2174/1573413715666191113145322.

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Background: Increasing the bioactivity of metallic implants is necessary for biomaterial applications where hydroxyapatite (HA) is used as a surface coating. In industry, HA is currently coated by plasma spraying, but this technique has a high cost and produces coating with short-term stability. Objectives: In the present study, electrophoretic deposition (EPD) was used to deposit nano-biphasic calcium phosphate compound (β-tri-calcium phosphate (β-TCP) /hydroxyapatite (HA)) bio-ceramics on the titanium surface. The microstructural, chemical compositions and bioactivity of the β- TCP/HA coatings were studied in a simulated body fluid solution (SBF). Methods: Scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDX) and Fourier transform infrared spectroscopy (FTIR) were used. Additionally, the antibacterial effect was studied by the agar diffusion method. The corrosion behavior of the β-TCP/HA coating on titanium surface (Ti) in the SBF solution at 37oC was investigated by means of electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization tests. Results: The Ti surface modification increased its biocompatibility and corrosion resistance in the simulated body fluid. The antibacterial inhibition activity of the β-TCP/HA bio-ceramic was enhanced by electroless silver deposition. The enhanced properties could be attributed to the use of nano-sized biphasic calcium phosphates in a low-temperature EPD process. Conclusions: The β-TCP/HA and β-TCP/HA/Ag coatings well protect Ti from the corrosion in SBF and endow Ti with biocompatibility. The β-4-TCP/HA/Ag/Ti substrate shows good antibacterial activity.

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Sobral, A. V. C., and César V. Franco. "Study of Corrosion Resistance of Sintered Fe-2%Ni, Fe-5%Ni and Fe 10%Ni with Electroactive Polymeric Coating of Poly trans-[RuCl₂(vpy)₄]." Materials Science Forum 530-531 (November 2006): 78–84. http://dx.doi.org/10.4028/www.scientific.net/msf.530-531.78.

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The use of generated coated polymeric films by electrochemistry means in the sintered metallic surfaces has been being the focus of our research aimed at the corrosion protection of small mechanical components obtained from powder metallurgy. The sintered alloys Fe- 2%Ni, Fe-5%Ni and 10%Ni with polymeric coating were tested using electrochemistry methods in corrosive solutions of NaCl 3%, KNO3 1.25M, H2SO4 0.5M, HNO3 0.5M, acetic acid 1%, oxalic acid 1% and lactic acid 1%. The electrochemistry corrosion tests were performed using two techniques, Eocp vs. Time and Potentiodynamic and they proved the efficiency of the polymeric coating on the corrosion protection of sintered alloys.

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Jiang, L., Z. Q. Chen, H. B. Lu, H. B. Ke, Y. Yuan, Y. M. Dong, and X. K. Meng. "Corrosion protection of NiNb metallic glass coatings for 316SS by magnetron sputtering." Journal of Materials Science & Technology 79 (July 2021): 88–98. http://dx.doi.org/10.1016/j.jmst.2020.12.004.

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Zheng, Shunli, Daniel Angel Bellido-Aguilar, Jun Hu, Yinjuan Huang, Xin Zhao, Zhen Wang, Xianting Zeng, Qichun Zhang, and Zhong Chen. "Waterborne bio-based epoxy coatings for the corrosion protection of metallic substrates." Progress in Organic Coatings 136 (November 2019): 105265. http://dx.doi.org/10.1016/j.porgcoat.2019.105265.

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Capp., J. A. "CORROSION AND PROTECTION OF METALS. A RATIONAL TEST FOR METALLIC PROTECTIVE COATINGS*." Journal of the American Society for Naval Engineers 26, no. 3 (March 18, 2009): 985–88. http://dx.doi.org/10.1111/j.1559-3584.1914.tb00331.x.

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Du, Bin, Shi Sheng Zhou, Na Li Li, and Nan Wang. "Research Progress of Surface Modification of Aluminum Powders for Corrosion Protection." Applied Mechanics and Materials 80-81 (July 2011): 70–75. http://dx.doi.org/10.4028/www.scientific.net/amm.80-81.70.

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As an important metallic powder, aluminum powders are used widely in coating, inks and plastic industry. However, it is necessary to treat the aluminum powders first to improve the properties of weather-resistance, anti-corrosion in acidic or basic media and compatibility with resin. The methods of surface treatment of aluminum powders including encapsulation and using corrosive inhibitors are summarized. The kinds of corrosive inhibitors used in the method of corrosion inhibition and their mechanisms are also reviewed. The processes and technologies of inorganic passivation, encapsulation by polymer absorption and by in situ polymerization are introduced. The research directions of aluminum powders are also presented.

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Wang, Xi, and G. S. Frankel. "The Effect of Trivalent Chromium Process on Al-Zn-In Pigments in Epoxy Primer on the Corrosion Protection of AA2024-T3." CORROSION 76, no. 1 (January 1, 2020): 103–13. http://dx.doi.org/10.5006/3393.

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Active metal pigments in metal-rich coatings are oxidized preferentially and provide sacrificial protection to more-noble metallic substrates. Al-rich primer (AlRP), which contains pigment particles made from an active aluminum alloy (Al-5Zn-0.02In), uses this mechanism to provide a chromate-free epoxy primer system. To address the high self-corrosion rate of active aluminum pigments, the active aluminum pigment particles are pretreated using trivalent chromium process (TCP). In this study, the effects of different TCP treatment times were evaluated, and coating protection properties were studied. Potentiodynamic polarization tests were performed in aerated 0.1 M NaCl solution for a TCP-treated bulk active aluminum alloy and for AA2024-T3. The potentiodynamic polarization curves show that the corrosion potential of the bulk active aluminum alloy is about 500 mV lower than that of AA2024-T3. Therefore, bulk active aluminum alloy is a candidate alloy for cathodic protection of AA2024-T3. In addition, the TCP treatment reduces the corrosion rate of the bulk active aluminum alloy by one order of magnitude. AlRP-coated AA2024-T3 panel samples were scribed and exposed in corrosion chambers, and the cross section of each coating was evaluated by scanning electron microscopy and energy dispersive x-ray spectroscopy mapping. The accelerated corrosion exposure results show that AlRP coatings containing TCP-treated particles provided better protection to the scribe than the one with bare pigment particles. The adhesion of the AlRPs based on pull-off adhesion tests was similar regardless of the TCP treatment time of the pigments, but the adhesion of AlRP was reduced in comparison to a neat epoxy coating.

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Berbel, Larissa Oliveira, Paulo Rogério Pinto Rodrigues, and Everson do Prado Banczek. "Aluminum Coating Obtained through the Sol-Gel Method to Protect Metallic Surfaces against Corrosion." Materials Science Forum 805 (September 2014): 190–95. http://dx.doi.org/10.4028/www.scientific.net/msf.805.190.

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Before metallic materials are painted, surface pre-treatments are usually applied, these are known as conversion treatments. Such treatments aim to slow the degradation of the organic coating/metallic substrate system in aggressive environments. Amongst the most effective conversion coatings for aluminum and its alloys, is the chromatization. However, the high toxicity of this process waste has led industry to ban the chromatization process from the market and seek new procedures to protect metallic surfaces which, at the same time, present lower toxicity and are efficient to protect against corrosion. This study aims to obtain a coating composed of aluminum oxide on the Al AA 3003 alloy, as a potential method to substitute the chromatization process. A study on the protection properties against corrosion of the base metal, coated with oxide, was developed. Open circuit potential tests, electrochemical impedance spectroscopy, and anodic potentiodynamic polarization curves were carried out in a Na2SO4 0,5 molL-1 solution and pH 4,0. The morphology characterization was performed employing the scanning electronic microscopy (SEM). Results indicated that the new coating presented better behavior than the chromatized samples, suggesting that the former can substitute the chrome coating.

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Janusz, M., L. Major, J. M. Lackner, B. Grysakowski, and H. Krawiec. "Microstructure characterization of localized corrosion wear of Cr/Cr2N+ a-C:H/a-C:H:Cr multilayer coatings on carbon fiber composites." Bulletin of the Polish Academy of Sciences Technical Sciences 65, no. 2 (April 1, 2017): 171–77. http://dx.doi.org/10.1515/bpasts-2017-0021.

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Abstract The use of carbon fiber composites (CFC) for different applications is widespread. Carbon-based materials show, however, significant oxidative degradation in air. Modern materials are subjected to aggressive, corrosive environment. This type of environment may strongly reduce their mechanical properties. For the protection of CFC, it was necessary to apply coatings to the composite surface. In the presented paper, a chromium/chromium nitride (Cr/Cr2N) multilayer structure has been selected as the inner part. The outer part of the coating was a hydrogenated amorphous carbon (a-C:H), gradually implanted by Cr nanocrystals. The application of transmission electron microscopy (TEM) indicated that the proposed deposition method allowed the formation of a Cr/Cr2N multilayer of Λ = 150 nm, topped with a-C:H+ Cr23C6 composite of a varied carbides density. The micro-hardness of the deposited coatings was up to 14 GPa (at a load of 2 and 5 mN). The microstructure of the deposited coatings was described in detail by means of TEM in the authors’ recently published paper [1]. This paper is a continuation thereof, aimed at describing microstructure changes after a localized corrosion process. In order to study localized corrosion in coatings, particularly in metallic (Cr) interlayers, the potential measurements and voltammetry experiments were performed in a Ringer solution. The open-circuit potential reaches stable values after a sufficient time period. The results indicated that the presence of a-C:H+Cr23C6, the outer part of the coating, speeds up the localized corrosion process in Cr interlayers in the inner part of a coating.

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Škugor Rončević, Ivana, Nives Vladislavić, Marijo Buzuk, Maša Buljac, and Anđela Lukin. "Corrosion protection of tin by some carboxylic acids in sodium chloride solution." Macedonian Journal of Chemistry and Chemical Engineering 39, no. 2 (October 26, 2020): 167. http://dx.doi.org/10.20450/mjcce.2020.2112.

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Tin is a moderately corrosion resistant material that is widely used in tinplate for food beverages. However, despite its excellent corrosion resistance, the presence of oxidizing agents enhances tin dissolution. Dissolution of metallic tin, especially from the inside of a can body into the food content has a major influence on the food quality and may cause toxicological effects. To overcome the problem, different chemical compounds are added. The most utilized inhibitors in the food industry are nitrites and nitrates well-known as hazardous to health. The present study aimed to investigate the influence of carboxylic acids on the corrosion resistance of tin since they are present in fruit juices and different foodstuffs. The corrosion protection efficiency of the carboxylate coatings was investigated in a sodium chloride solution using electrochemical and spectroscopic techniques. The structural characteristics of the surface coatings were investigated using the FTIR spectroscopy and optical microscope.

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Froitzheim, J., and J. E. Svensson. "Nanocoatings for SOFC Interconnects - Mitigating Chromium Volatilization and Improving Corrosion Properties." Materials Science Forum 696 (September 2011): 412–16. http://dx.doi.org/10.4028/www.scientific.net/msf.696.412.

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Two important degradation mechanisms in Solid Oxide Fuel Cells (SOFC) are directly related to the metallic interconnects. The formation of volatile chromium oxides from metallic interconnects commonly causes fast degradation in cell performance due to poisoning the cathode. Secondly is the ability of the metallic interconnect to form a thin protective oxide one of the most important lifetime limiting factors for SOFC. Chromium volatilization of various uncoated steels is studied as a function of temperature by a recently developed denuder technique which allows time resolved quantification of volatile chromium species. The inhibition of Cr evaporation by Co thin film coatings (800nm) is investigated; it will be shown that these coatings are more effective than much thicker ceramic coatings that are commonly used for this purpose. In order to increase the lifetime of the metallic components in SOFC nano-coatings of reactive elements (RE) have been investigated as well. The application of such coatings can reduce the corrosion rates substantially and thus increase the lifetime of the fuel cell stack. It will be shown that it is possible to combine the positive effects of RE with the beneficial effects of a Co coating and thus to obtain an interconnect material with low Cr evaporation and increased oxidation resistance.

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Kriba, Ilhem, and A. Djebaili. "The Interaction between Particles and a Plasma Beam in the Thermal Projection Process." Advanced Materials Research 83-86 (December 2009): 801–9. http://dx.doi.org/10.4028/www.scientific.net/amr.83-86.801.

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Plasma spray processes have been widely used to produce high performance coatings of a wide range of Materials (metallic, non-metallic, ceramics), offering protection from, eg. wear, extreme temperature, chemical attack and environmental corrosion. To obtain good quality coatings, spray parameters must be carefully selected. Due to the large variety in process parameters, it is difficult to optimize the process for each specific coating and substrate combinations. Furthermore modelling the spray process allows a better understanding of the process sequences during thermal spraying. Good agreement of the virtual spraying process with the real coating formation is achieved by modelling the particular process steps. The simulation of coating formation to estimate the process parameters is an important tool to develop new coating structures with defined properties. In this work, the process of plasma sprayed coating has been analyzed by numerical simulation. Commercial code is used to predict the plasma jet characteristics, plasma –particle interaction, and coating formation. Using this model we can obtain coating microstructure and characteristics which form a foundation for further improvement of an advanced ceramic coating build up model.

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PIRHADY TAVANDASHTI, NAHID, and SOHRAB SANJABI. "Synthesis of Oxide Nanoparticles in Hybrid Nanocomposite Coatings as Nanoreservoirs of Corrosion Inhibitors." International Journal of Modern Physics: Conference Series 05 (January 2012): 234–41. http://dx.doi.org/10.1142/s2010194512002073.

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Nanostructured hybrid silica/epoxy films containing boehmite nanoparticles were investigated in the present work as pretreatments for AA2024 alloy. To produce the nanocomposite sol-gel films, boehmite nanoparticles prepared from hydrolysis/condensation of aluminum isopropoxide ( AlI ) were doped into another hybrid organosiloxane sol. The produced oxide nanoparticles have the capability to act as nanoreservoirs of corrosion inhibitors, releasing them controllably to protect the metallic substrate from corrosion. For this purpose the corrosion inhibitor, cerium nitrate, was introduced into the sol-gel system via loading the nanoparticles. The morphology and the structure of the hybrid sol-gel films were studied by Scanning Electron Microscopy (SEM). The corrosion protection properties of the films were investigated by Potentiodynamic Scanning (PDS) and Electrochemical Impedance Spectroscopy (EIS). The results show that the presence of boehmite nanoparticles highly improved the corrosion protection performance of the silica/epoxy coatings. Moreover, they can act as nanoreservoirs of corrosion inhibitors and provide prolonged release of cerium ions, offering a self-healing property to the film.

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Journal articles on the topic 'Metallic coatings; Corrosion protection'

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