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We present an autonomous scanning droplet cell platform designed for on-demand alloy electrodeposition and real-time electrochemical characterization. Automation and machine learning are currently driving rapid innovation in high-throughput and autonomous materials design and discovery. We present two alloy design vignettes: one focusing on a multi-objective corrosion resistant alloy optimization and a study highlighting the complexity of the multimodal characterization needed to provide insight into the underlying structural and chemical factors that drive observed material behavior. This motivates a close coupling between autonomous research platforms and scientific machine learning methodology that blends mechanistic physical models and black box machine learning models. Finally, we reflect on our early efforts in on-demand alloy deposition, highlighting some of the challenges. This emerging research area presents new opportunities to accelerate materials synthesis, evaluation, and hence discovery and design. [ABSTRACT FROM AUTHOR]

This article discusses the methods of improving the corrosion resistance of fuel rod claddings from E110 zirconium alloy performed at TRINITI State Research Center using coatings (Al, Al2O3, Cr) applied by pulsed laser deposition as well as magnetron sputtering and galvanic deposition of chromium. Some results are presented regarding studies of adhesion, microstructure, and corrosion resistance of chromium coatings deposited by various methods. [ABSTRACT FROM AUTHOR]

The article is devoted to the study of the corrosion resistance of steel pile supports made of pipe steel 09Mn2Si (09G2S), under conditions of cyclic wetting (conditional waterline), where conditions are created for the occurrence of corrosion processes at maximum speeds, and also a study of the protective ability of zinc coating applied to the railing (balustrade) of a steel bridge made of carbon steel of normal quality (St3). It was the bridge structures that became the subject of research. We considered the effects of cyclic wetting, wear, and climatic factors on the materials of piled supports, fences, and coatings intended for operation in the marine structure. We investigated the corrosion resistance of the 09Mn2Si steel used as pile supports of offshore structures. We have found that the corrosion rate of the 09Mn2Si steel does not exceed 0.32 mm/year in the zone of cyclic wetting. We have confirmed that the corrosion rate of steel practically does not change in the sections with damaged coatings and does not depend on the area of the uncoated zone. Measuring the electrochemical potential of 09Mn2Si steel, we have found that short-term friction against a solid only weakly affects the corrosion rate of steel in seawater. We have proposed a methodological approach to assessing the service life of hot-dip galvanized coatings on components of steel structures made of carbon steel of normal quality (St3) intended for operation in marine conditions. A forecast of the durability of 120 μm-thick zinc coatings, expected to provide anti-corrosion protection of steel products for 60 years, was made based on the proposed technique.

Zinc (Zn) and zinc–nickel (Zn–Ni) electrodeposition has been widely used in many industries, such as automotive and aerospace, for corrosion protection of steel components owing to their excellent corrosion resistance. Conventional zinc and zinc–nickel electrodeposition is performed in different types of aqueous baths (acid and alkaline). Such electrolytes suffer from certain drawbacks such as hydrogen gas evolution, low coulombic efficiencies, and environmental toxicity. Electrodeposition of Zn and Zn–Ni alloys from ionic liquids has gained significant attention in aerospace and automotive sectors owing to the different environments they provide for electrodeposition. This paper reviews the progress in deposition of zinc and zinc-nickel alloys in non-aqueous systems, especially ionic liquids. In addition, the challenges and technological developments associated with the Zn and Zn–Ni deposition on different substrates and the factors that need to be considered while electroplating at an industrial scale are discussed. [ABSTRACT FROM AUTHOR]

Zinc (Zn) and zinc–nickel (Zn–Ni) electrodeposition has been widely used in many industries, such as automotive and aerospace, for corrosion protection of steel components owing to their excellent corrosion resistance. Conventional zinc and zinc–nickel electrodeposition is performed in different types of aqueous baths (acid and alkaline). Such electrolytes suffer from certain drawbacks such as hydrogen gas evolution, low coulombic efficiencies, and environmental toxicity. Electrodeposition of Zn and Zn–Ni alloys from ionic liquids has gained significant attention in aerospace and automotive sectors owing to the different environments they provide for electrodeposition. This paper reviews the progress in deposition of zinc and zinc-nickel alloys in non-aqueous systems, especially ionic liquids. In addition, the challenges and technological developments associated with the Zn and Zn–Ni deposition on different substrates and the factors that need to be considered while electroplating at an industrial scale are discussed.

Yttrium oxide coatings on graphite substrates were prepared by atmospheric plasma spray technique. Temperature and velocity of the yttrium oxide particles during the plasma spray process were measured by ‘spraywatch’ diagnostics system. Coatings were characterized for phase composition, microstructure and thermal stability. Dense adherent coatings could be deposited at 24 kW power. Corrosion behaviour of the coatings in molten uranium was studied by using differential thermal analysis (DTA) up to 1473 K. The results showed that the coatings offered sufficient protection to graphite against corrosion by molten uranium. [ABSTRACT FROM AUTHOR]

Corrosion is one of the major destruction processes involved in material loss, and its prevention is paramount in protecting investments. The present work shows a new contribution to the design of a new protective system based on poly(orthophenylenediamine) (PoPD)-nano-TiO2 composites. The structure and properties of PoPD-TiO2 nanocomposites were characterized by Fourier transform infrared spectroscopy (FT-IR), Cyclicvoltammetry (CV), Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) techniques. Thermal stability of the composite was studied by Thermogravimetric analysis (TGA). The anti-corrosion behavior of PoPD-TiO2 nanocomposites has been investigated in 3.5 wt.% NaCl solution using potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) measurements. Corrosion studies revealed that PoPD-TiO2 nanocomposites coating exhibited excellent anti-corrosive properties compared with PoPD coated and uncoated 316L SS. [ABSTRACT FROM AUTHOR]

Abstract: Hydroxyapatite (HAp) coatings were uniformly formed on pure Mg by a hydrothermal treatment using a C10H12N2O8Na2Ca (Ca-EDTA) solution. The growth mechanism of the HAp coating was investigated with XRD, SEM and TEM. At the initial stage, dome-shape HAp precipitates were formed on the Mg. Subsequently, the precipitates grew and the coating became a dual-layer consisting of an inner dense HAp layer and outer course layer consisting of rod-like HAp crystals. The protectiveness of the coatings with different treatment times was investigated by a polarization test in a 3.5wt.% NaCl solution. The corrosion current density decreased with the growth of the HAp coating. [Copyright &y& Elsevier]

This study examines the possibility of using poly( o-toluidine)/CdO (POT-CdO) nanoparticle composite coating for corrosion protection of mild steel in chloride environment. The POT-CdO nanoparticle composite coating was synthesized on mild steel from aqueous tartrate solution containing CdO-nanoparticles (size ~18 nm) by using cyclic voltammetry. These coatings were characterized by cyclic voltammetry, UV–Visible absorption spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction measurements. The corrosion protection aspects of the resulting POT-CdO nanocomposite structure were investigated in aqueous 3% NaCl solution by potentiodynamic polarization technique and electrochemical impedance spectroscopy. The results of these investigations reveal that the POT-CdO nanoparticle composite acts as a protective coating on mild steel and reduces the corrosion rate of mild steel almost by factor of 70. [ABSTRACT FROM AUTHOR]

Abstract: Poly(o-anisidine) (POA) coatings were synthesized on brass by electrochemical polymerization of o-anisidine in aqueous salicylate solution by using cyclic voltammetry. These coatings were characterized by cyclic voltammetry, UV–visible absorption spectroscopy, Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The corrosion protection aspects of POA coatings on brass in aqueous 3% NaCl solution were investigated by potentiodynamic polarization technique and electrochemical impedance spectroscopy (EIS). The potentiodynamic polarization measurements show that the POA coating has ability to protect the brass against corrosion. The corrosion potential was about 0.204V versus SCE more positive for the POA coated brass than that of uncoated brass and reduces the corrosion rate of brass almost by a factor of 800. The corrosion behavior of the POA coatings was also investigated by EIS through immersion tests performed in aqueous 3% NaCl solution. The evolution of the impedance parameters with the immersion time was studied and the results show that the POA acts as a protective coating on brass against corrosion in 3% NaCl solution. The water uptake and delamination area were also determined to further support the corrosion protection performance of the POA coating. [Copyright &y& Elsevier]

Abstract: Poly(o-ethylaniline) coatings were synthesized on copper (Cu) by electrochemical polymerization of o-ethylaniline in an aqueous salicylate solution by using cyclic voltammetry. The characterization of these coatings was carried out by cyclic voltammetry, UV–visible absorption spectroscopy, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The results of these characterizations indicate that the aqueous salicylate solution is a suitable medium for the electrochemical polymerization of o-ethylaniline to generate strongly adherent and smooth poly(o-ethylaniline) coatings on Cu substrates. The performance of poly(o-ethylaniline) as protective coating against corrosion of Cu in aqueous 3% NaCl was assessed by the potentiodynamic polarization technique and electrochemical impedance spectroscopy (EIS). The results of these studies demonstrate that the poly(o-ethylaniline) coating has ability to protect the Cu against corrosion. The corrosion potential was about 0.078 V versus SCE more positive in aqueous 3% NaCl for the poly(o-ethylaniline) coated Cu (∼15 μm thick) than that of uncoated Cu and reduces the corrosion rate of Cu almost by a factor of 70. [Copyright &y& Elsevier]

Abstract: A process to transform the commercially available yttrium oxide powder (M/s. IRE) into thermal spray grade powder and development of plasma spray coating of it on graphite/metallic substrate are described. Experimental results show that the synthesized powder had very good flow characteristics and could be used for plasma spray deposition efficiently. [Copyright &y& Elsevier]

Abstract: Poly(o-ethoxyaniline) (POEA) coatings were synthesized on copper (Cu) by electrochemical polymerization of o-ethoxyaniline in aqueous salicylate solution by using cyclic voltammetry. These coatings were characterized by cyclic voltammetry, UV–vis absorption spectroscopy, Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The performance of POEA as protective coating against corrosion of Cu in aqueous 3% NaCl was assessed by the potentiodynamic polarization technique and electrochemical impedance spectroscopy (EIS). The results of the potentiodynamic polarization and EIS studies demonstrate that the POEA coating has ability to protect the Cu against corrosion. The corrosion potential was about 0.330V versus SCE more positive in aqueous 3% NaCl for the POEA coated Cu than that of uncoated Cu and reduces the corrosion rate of Cu almost by a factor of 140. [Copyright &y& Elsevier]

Abstract: The poly(o-anisidine-co-o-toluidine) coatings were synthesized on copper substrates by electrochemical copolymerization of o-anisidine with o-toluidine using sodium salicylate as supporting electrolyte. These coatings were characterized by cyclic voltammetry, UV–vis absorption spectroscopy, Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR) and scanning electron microscopy (SEM). The formation of the copolymer with the mixture of monomers in the aqueous sodium salicylate solution was ascertained by a critical comparison of the results obtained with the polymerization of the individual monomers, o-anisidine and o-toluidine, respectively. The corrosion protection aspects of poly(o-anisidine-co-o-toluidine) coatings to copper was investigated in aqueous 3% NaCl solution by potentiodynamic polarization technique and electrochemical impedance spectroscopy (EIS). The results of the potentiodynamic polarization measurements and EIS studies showed that the poly(o-anisidine-co-o-toluidine) coatings provided the effective corrosion protection to copper than that of respective homopolymers. The corrosion rate is observed to depend on the feed ratio of o-toluidine used for the synthesis of the copolymer coatings. [Copyright &y& Elsevier]

Abstract: The poly(o-ethylaniline) coatings were electrochemically synthesized on 304-stainless steel by using cyclic voltammetry from an aqueous salicylate medium. Cyclic voltammetry, UV–vis absorption spectroscopy, Fourier transform infrared spectroscopy and scanning electron microscopy were used to characterize these coatings, which indicates that the aqueous salicylate solution is a suitable medium for the electrochemical polymerization of o-ethyaniline on 304-stainless steel. The performance of poly(o-ethylaniline) as protective coating against corrosion of 304-stainless steel in aqueous 3% NaCl was evaluated by the open circuit potential measurements, potentiodynamic polarization technique, cyclic potentiodynamic polarization measurements and electrochemical impedance spectroscopy. The results of the potentiodynamic polarization and cyclic potentiodynamic polarization demonstrate that the poly(o-ethylaniline) coating provides excellent protection to both localized and general corrosion of 304-stainless steel. The corrosion potential was about 0.190V more positive in aqueous 3% NaCl for the poly(o-ethylaniline) coated steel than that of bare steel and reduces the corrosion rate of steel almost by a factor of 20. [Copyright &y& Elsevier]

Abstract: Poly(2,5-dimethylaniline) coatings were synthesized on copper (Cu) by electrochemical polymerization of 2,5-dimethylaniline in aqueous salicylate solution by using cyclic voltammetry. The characterization of these coatings was carried out by cyclic voltammetry, UV–visible absorption spectroscopy, Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The results of these characterizations indicate that the aqueous salicylate solution is a suitable medium for the electrochemical polymerization of 2,5-dimethylaniline to generate strongly adherent and smooth poly(2,5-dimethylaniline) coatings on Cu substrates. The performance of poly(2,5-dimethylaniline) as protective coating against corrosion of Cu in aqueous 3% NaCl was assessed by the potentiodynamic polarization technique. The results of the potentiodynamic polarization demonstrate that the poly(2,5-dimethylaniline) coating has ability to protect the Cu against corrosion. The corrosion potential was about 0.078V versus SCE more positive in aqueous 3% NaCl for the poly(2,5-dimethylaniline) coated Cu than that of uncoated Cu and reduces the corrosion rate of Cu almost by a factor of 31. [Copyright &y& Elsevier]

Abstract: In the present study, surface engineering research related to thermally sprayed wear and corrosion resistant coatings modified by in-situ and post-treatment by novel high power lasers (Nd:YAG and diode lasers) has been carried out. The main aim of the study was to create experimental based information and knowledge on simultaneous remelting of thermally sprayed (plasma, HVOF, flame) single layers for production of metallurgically bonded, dense corrosion and wear resistant coatings on surfaces of steels. The main focus of research was to estimate the needed processing parameters, which enable simultaneous laser-assisted thermal spraying. The microstructures and hardness-profiles for the coatings prepared by laser-assisted thermal spraying are also introduced. [Copyright &y& Elsevier]

Abstract: Alloy 600 and Alloy 800H are susceptible to metal dusting. Both alloys were thermally sprayed with two different corrosion resistant coatings: Ni50Cr and Ni31Cr11Al0.6Y. Laser remelting was used to enhance further the effectiveness of these coatings to resist metal dusting by eliminating interconnected porosity and improving coating adhesion. Uncoated, coated and laser-treated coated samples of Alloy 600 and Alloy 800H were exposed to a mixed gas atmosphere (20% H2, 80% CO at 650 °C). Samples were examined in plan and cross-section using optical and scanning electron microscopy, electron probe microanalysis and X-ray diffraction. The extent of carbon deposition was tracked by mass difference measurements at intervals during exposure. The thermally sprayed coatings enhanced metal dusting resistance by acting as physical barriers to carbon ingress. The NiCrAlY coating performed well on both substrates. The NiCr coating itself underwent metal dusting and spalled from Alloy 800H due partly to CTE mismatch stresses. Laser treatment of both coatings successfully eliminated interconnected porosity and hence enhanced metal dusting resistance. [Copyright &y& Elsevier]

Abstract: Poly(o-toluidine) (POT) coatings were synthesized on copper (Cu) by electrochemical polymerization of o-toluidine using aqueous sodium oxalate solution as supporting electrolyte. The resulting coatings were uniform, compact and strongly adherent to the Cu substrate. These coatings were characterized by using cyclic voltammetry, UV-visible absorption spectroscopy, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) measurements and X-ray photoelectron spectroscopy (XPS). The results of these studies reveal that the sodium oxalate is suitable supporting electrolyte for the electrochemical polymerization of o-toluidine on Cu substrate. It is found that the electrochemical polymerization of o-toluidine takes place after the passivation of the Cu substrate via formation of copper oxalate (CuC2O4, H2O) layer, which is confirmed by XRD and XPS. The optical absorption spectroscopy study reveals the exclusive formation of the pernigraniline base (PB) form of POT. [Copyright &y& Elsevier]

Abstract: This study examines the use of poly(o-toulidine) (POT) coatings for corrosion protection of copper (Cu) in an aqueous solution of 3% NaCl. The POT coatings were synthesized on Cu substrates under cyclic voltammetric conditions from an aqueous solution of sodium oxalate. The resulting, POT coatings were uniform, shiny and strongly adherent to the Cu substrates. These coatings were characterized by cyclic voltammetry (CV), UV–visible absorption spectroscopy, Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The ability of POT to serve as a corrosion protective coating for Cu was examined by potentiodynamic polarization measurements and CV. The results of this study clearly reveal that the POT acts as corrosion protective coating on Cu and reduces the corrosion rate of Cu almost by a factor of 40. [Copyright &y& Elsevier]

Poly(o-anisidine) (POA) coatings were synthesised on low carbon steel substrates by electrochemical polymerisation of o-anisidine under cyclic voltammetric conditions from an aqueous solution of sodium tartrate. The resulting POA coatings were uniform and strongly adherent to the substrates. The coatings were characterised by cyclic voltammetry, UV-visible absorption spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction measurements and scanning electron microscopy. The ability of the POA coatings to protect the steel in an aqueous 3%NaCl solution was evaluated by the potentiodynamic polarisation technique and cyclic voltammetry. It was found that the POA coating ennobled the corrosion potential and significantly reduced the corrosion rate of the steel. [ABSTRACT FROM AUTHOR]

Thermally sprayed fluoropolymer, polyvinylidene fluoride (PVDF), ethylene chlorotrifluoroethylene (ECTFE), perfluoroalkoxy alkane (PFA) and fluorinated perfluoroethylenepropylene (FEP) coatings were produced by flame and plasma spraying processes. It was possible to produce high quality coatings by these techniques. These coating processes are one-step methods in which post heat treatments are not required, in contrast to conventional electrostatic deposition methods. Morphology and particle size distributions were determined for each fluoropolymer powder. The coatings prepared by plasma and flame spraying were studied by optical microscope, salt spray test and liquid immersion tests. Sprayed coatings were found to be poreless and very smooth. In salt spray test, no corrosion invasion was found. In both liquid immersion tests (pH values −0.7 and 14) only PFA coating performed well. The other coatings showed a little corrosion in liquid immersion tests. That was observed as darkening of the fluoropolymer coating in the areas that were exposed to corrosive liquid. According to sectioned micrographs, the coatings were fully dense. [Copyright &y& Elsevier]

Poly(N-ethyl aniline) coating was electrodeposited onto Al-2024 by using cyclic voltammetry. The coating was characterized by infrared spectroscopy, cyclic voltammetry and UV-Vis spectroscopy. The corrosion resistance of the film was evaluated by dc polarization studies. These coatings were formed in aqueous solution of oxalic acid. The concentration of monomer and oxalic acid were kept constant at 0.1 and 0.3 M, respectively. The formation of the polymer coating was monitored by cyclic voltammetry and infrared spectroscopy. Preliminary dc polarization results show that poly(N-ethyl aniline) has a corrosion rate of about 0.004 mmpy, which is significantly lower (about one order of magnitude) than that for the non-coated Al-2024. [Copyright &y& Elsevier]

Zeolites are crystalline nanoporous aluminosilicates. Thanks to their intrinsically nanoporous structure they are widely used as molecular sieves, for exchanging ions, or, also thanks to the high surface area of these structures, for catalytic applications. Furthermore, thanks to their thermal and chemical stability, in recent years zeolite coatings have been evaluated for application as anti-corrosion coatings. The non-toxicity of this class of coatings makes it possible that they will be an environmentally friendly alternative to conventional chromate-based coatings. This article provides a brief review of the anti-corrosion performance of zeolite coatings, applied by direct synthesis technique to several metals and alloys, as discussed in the literature. After a short description of the microstructure and properties of zeolites, the discussion addresses the research activities related to this topic, as reported in the literature. Comparative analysis of literature results supported the dry-gel conversion method as a promising approach that combines a simplified synthesis procedure with anti-corrosion coating performance. Based on these considerations, an evaluation of future trends is discussed along with the final remarks. [ABSTRACT FROM AUTHOR]