Abstract IE(%) of SCLAE on CR of CS immersed in 1 N HCl was herein assessed by the WL method. The former increased and the latter decreased in the solution with higher Ct of SCLAE. The inhibitor blocked MS corrosion active sites, and created a protective layer that covered its surface. Pc constituents of SCLAE allowed the interaction between their hetero atoms and the metal ions from the CS surface. These Pc were responsible for the CI of CS. Elc studies were herein used to confirm the formation of a protective layer on the CS surface. They were further reinforced by surface analysis techniques, such as FTIR and SEM. EDAX was used to analyze the elements present on the CS surface after its immersion in 1 N HCl without and with SCLAE. Ra of polished, corroded and inhibited CS surfaces was analyzed by SEM and AFM.

Abstract The structural integrity is generally given by the mechanical behavior of the joints, and among these are the welded joints. During service, variable loads may appear over time, so it is necessary to know data to predict the fatigue failure of welds. This article aims to determine the S-N curve of an AISI 1015 steel butt-welded joint, manufactured by the flux-cored arc welding process. The filler material is the ER71-T wire and the protection gas was carbon dioxide. The fatigue tests were carried out according to the ASTM 739-91 standard in a MTS810 universal testing machine. Rectangular cross section specimens were used. The load cycle was asymmetric in tensile, with an asymmetry ratio of 0,1. It was obtained that the fatigue strength limit 01 for the tested joint is equal to 161,4 MPa, at a cut point of 1 500 000 cycles.

Resumen La integridad estructural generalmente está dada por la resistencia mecánica de las uniones, y entre estas se encuentran las uniones soldadas. Durante el servicio pueden aparecer cargas variables en el tiempo, por lo que es necesario conocer datos que permitan predecir el fallo por fatiga de las soldaduras. Este artículo tuvo como objetivo determinar la curva S-N de una unión soldada a tope de acero AISI 1015, fabricada mediante el proceso de soldadura por arco con núcleo fundente. El material de aporte fue el alambre ER71-T y el gas de protección fue dióxido de carbono. Los ensayos a fatiga se realizaron de acuerdo a la norma ASTM 739-91 en una máquina universal MTS810. Se utilizaron probetas de sección transversal rectangular. El ciclo de carga fue asimétrico a tracción, con un coeficiente de asimetría de 0,1. Se obtuvo que el límite de resistencia a la fatiga 01 para la unión ensayada es igual a 161,4 MPa, a un punto de corte de 1 500 000 ciclos.

Abstract: In this investigation was developed a comparative study of the superficial hardness of AISI 8620 steel thermally treated by carburizing, by the use of vegetable and coking coals. The objective was to propose an alternative to the element used to generate the carburizing atmosphere. The previous stages have been described, such as the preparation of the material and its verification, as well as the dimensions and characteristics, defined by the ASTM E-18 standard. By considering four variables, each one with two levels, an orthogonal array matrix of 16 experiments was generated. The surface hardness measurements were processed through an analysis of variance (ANOVA), where the significance of each variable considered as a factor was obtained. Coking coal can be used as an element for the generation of carburizing atmosphere since a maximum relative error of 3.86% was obtained between the experimental values and the values in the literature. In contrast, the vegetable coal did not improve the mechanical properties of the steel, reaching an average hardness of 25.95 HRC after heat treatments.

Resumen: En esta investigación, se desarrolló el estudio comparativo de la dureza superficial del acero AISI 8620 tratado térmicamente con cementación, utilizando carbón vegetal y coque. El objetivo fue proponer una alternativa al elemento utilizado para generar la atmósfera de cementado. Se describen las etapas previas, tales como la preparación del material y la verificación del mismo, también se analizaron las dimensiones y características que define la norma ASTM E-18. Al considerar cuatro variables, cada una con dos niveles, se generó una matriz de arreglo ortogonal de 16 experimentos. Las mediciones de dureza superficial fueron procesadas mediante un análisis de varianza (ANOVA), se obtuvo la significancia de cada variable considerada como factor. El carbón coque puede utilizarse como elemento para la generación de atmósfera de cementado, ya que se obtuvo un error relativo máximo de 3.86% entre los valores experimentales y los valores presentes en la literatura. Por otra parte, el carbón vegetal no mejoró las propiedades mecánicas del acero, alcanzando una dureza en promedio de 25.95 HRC luego de los tratamientos térmicos.

SYNOPSIS Ferrochrome (FeCr) is a vital ingredient in stainless steel production and is commonly produced by smelting chromite ores in submerged arc furnaces. Silicon (Si) is a componrnt of the FeCr alloy from the smelting process. Being both a contaminant and an indicator of the state of the process, its content needs to be kept within a narrow range. The complex chemistry of the smelting process and interactions between various factors make Si prediction by fundamental models infeasible. A data-driven approach offers an alternative by formulating the model based on historical data. This paper presents a systematic development of a data-driven model for predicting Si content. The model includes dimensionality reduction, regularized linear regression, and a boosting method to reduce the variability of the linear model residuals. It shows a good performance on testing data (R² = 0.63). The most significant predictors, as determined by linear model analysis and permutation testing, are previous Si content, carbon and titanium in the alloy, calcium oxide in the slag, resistance between electrodes, and electrode slips. Further analysis using thermodynamic data and models, links these predictors to electrode control and slag chemistry. This analysis lays the foundation for implementing Si content control on a ferrochrome smelter.

ABSTRACT There is a growing need for intervention in existing structures to recover or increase strength capacity. The use of composite materials, such as carbon fiber, has been efficient, but cost is an obstacle. The application of steel bars as a strengthening element is an alternative and technically viable material, but there are few studies in the literature. This work carried out an experimental series with three reinforced concrete beams without transverse reinforcement, and strengthened in shear with steel bars using the near-surface mounted (NSM) technique. The load, displacement and cracking pattern were monitored in the experiment. The results demonstrated the efficiency of the strengthening with an increase of 69% in the ultimate load and 63% in the load for the appearance of the first cracks compared to the reference beam. The strengthening also increased the ductility of the beams before sudden shear failure. Numerical models via the finite element method (FEM) were carried out in the ABAQUS software using different elements and meshes. The numerical results were validated with the experimental results, and it was observed that the use of quadratic elements compared to linear elements can better represent the cracking pattern and the load capacity of the beams. The mean ratio of numerical/experimental results for maximum load of strengthening beams was 0.94. materials fiber efficient obstacle material literature reinforcement nearsurface near surface NSM (NSM technique experiment 69 63 beam failure FEM (FEM meshes numericalexperimental 094 0 94 0.94 6 09 9 0.9 0.

RESUMO Há uma necessidade crescente de intervenção nas estruturas de concreto armado existentes para recuperar ou aumentar a sua capacidade resistente. O uso de materiais compósitos, como a fibra de carbono, tem sido eficiente, mas o custo ainda é um entrave. A aplicação de barras de aço como elemento de reforço apresenta-se como material alternativo e tecnicamente viável, porém existem poucos trabalhos na literatura. Desse modo, este trabalho realizou uma série experimental com três vigas de concreto armado sem armadura transversal, e reforçadas ao cisalhamento com barras de aço utilizando a técnica near-surface mounted (NSM). Foram monitorados no experimento a carga, o deslocamento e o padrão de fissuração. Os resultados demonstraram a eficiência do reforço com aumento de 69% da carga última e 63% da carga para surgimento das primeiras fissuras comparados a viga de referência. O reforço também aumentou a ductibilidade das vigas antes da ruptura brusca por cisalhamento. Modelos numéricos via método dos elementos finitos (MEF) foram realizados no software ABAQUS utilizando diferentes tipos de elementos e malhas. Os resultados numéricos foram validados com os resultados experimentais e foi observado que o uso de elementos quadráticos comparados a elementos lineares consegue representar melhor o padrão de fissuração e a capacidade de carga das vigas. A relação média dos resultados numérico/experimental para carga máxima das vigas reforçadas foi de 0,94. resistente compósitos carbono eficiente entrave apresentase apresenta se viável literatura modo transversal nearsurface near surface NSM. NSM . (NSM) 69 63 referência MEF (MEF malhas numéricoexperimental numérico 094 0 94 0,94 (NSM 6 09 9 0,9 0,

The use of fluorescent nanomaterials in various fields of study has become increasingly common. In this work, the use of carbon quantum dots as a corrosion marker in carbon steel is proposed. To produce the sensor, carbon quantum dots based on ethylenediamine and citric acid were used, dissolved in a polymeric matrix. The quantum dot used showed a quantum yield of 42.34%. The nanomodified coatings emitted blue light under ultraviolet radiation lamp. However, it was observed that there is a loss of photoluminescence in the coating on the carbon steel substrate compared to the coating on the polymeric substrate, which maintained photoluminescence activity after natural exposure. Thus, it is inferred that the loss of photoluminescence may be associated with the corrosion process. common work proposed sensor matrix 4234 42 34 42.34% lamp However exposure Thus process 423 4 3 42.34 42.3 42.

Resumen Centrándose en la industria siderúrgica a carbón en el Valle del Río Doce (este de Minas Gerais), este artículo propone comprender la relación entre la minería a escala industrial y la transición de las fábricas de hierro a las grandes acerías y el proceso de devastación de la Mata Atlántica. Los estudios sobre la industria siderúrgica que destaquen la presión ejercida por las centrales de carbón sobre la Mata Atlántica son casi inexistentes. Utilizando en particular informes técnicos, estadísticas oficiales, publicaciones periódicas y centrándonos en la empresa Belgo-Mineira, presentamos un conjunto de datos que nos permiten medir los impactos de la industria siderúrgica sobre el bosque. Para obtener una visión más profunda, el objetivo principal fue estimar la cantidad de extracción forestal para servir a la industria del acero entre 1936 y 1954. Los datos de esta investigación muestran que la industria del acero al carbón dio un aspecto distinto al fenómeno de frontera. Gerais, Gerais , Gerais) inexistentes técnicos oficiales BelgoMineira, BelgoMineira Belgo Mineira, Mineira Belgo-Mineira bosque profunda 193 1954 frontera 19 195 1

Abstract Focusing on the charcoal-fired steel industry in the Doce River Valley (rural eastern Brazil), this article sets out to understand the relationship between industrial-scale mining and the transition from iron factories to large steel mills. At the same time, it addresses the further destruction of the Atlantic Forest. Studies on the steel industry that highlight the pressure exerted on the Atlantic Forest by charcoal plants are almost nonexistent, however. Turning to technical reports, official statistics, journals, and other media sources and centering attention on Belgo-Mineira company, it highlights a set of data that enables us to measure the impacts of the charcoal-fired steel industry on forests. In order to get a deep insight, the main aim was to estimate the amount of forest extraction to serve the steel industry from 1936 to 1954. The data from this research show that the charcoal-fired steel industry gave a distinctive cast to the phenomenon of the agricultural frontier. charcoalfired fired rural Brazil, Brazil , Brazil) industrialscale industrial scale mills time nonexistent however reports statistics journals BelgoMineira Belgo Mineira company forests insight 193 1954 frontier 19 195 1

Resumo Com foco na indústria siderúrgica a carvão vegetal no Vale do Rio Doce (leste de Minas Gerais), o artigo propõe compreender a relação entre as grandes siderúrgicas e a devastação da Mata Atlântica. Estudos sobre a indústria siderúrgica que destacam a pressão exercida sobre a Mata Atlântica pelas carvoarias são quase inexistentes. Nesse sentido, recorrendo a relatórios técnicos, estatísticas oficiais, periódicos e outras fontes de mídia e centrando à atenção na empresa Belgo-Mineira, destaca-se um conjunto de dados que nos permite mensurar os impactos da indústria siderúrgica a carvão vegetal sobre a floresta. O resultado principal são as estimativas de extração florestal para servir a indústria siderúrgica entre 1936 e 1954. Os dados desta pesquisa mostram que a indústria siderúrgica a carvão vegetal deu um aspecto distinto ao fenômeno da fronteira em razão da centralidade do carvão. leste Gerais, Gerais , Gerais) inexistentes sentido técnicos oficiais BelgoMineira, BelgoMineira Belgo Mineira, Mineira Belgo-Mineira destacase destaca se floresta 193 1954 19 195 1

The industry's principal objective is to comprehend the optimal application of each metal alloy in terms of corrosion resistance. A key focus lies in exploring alternative approaches to address this corrosive process in a manner that is both sustainable and economically feasible. The major strategy to mitigate this contest involves the utilization of inhibitors. However, it is imperative to note that certain inhibitors pose environmental risks. This study explores the effect of the addition of protic ionic liquids (PILs) on the corrosion of carbon steel (A36) in a saline solution (3.5 wt% NaCl), considering variations in pH and temperature. It focuses on understanding the effects of pH and temperature on the PILs' ability to protect the steel surface. Notably, changes in pH do not affect the protective capacity of the inhibitors. Efficiency values exceeding 72% were achieved under both acidic conditions tested. The study reveals two scenarios: At 40 °C, the PILs effectively protect the steel, with an efficiency of approximately 74% at concentrations of 500 and 1000 ppm. However, at 60 °C, efficiency decreases notably, reaching a maximum of 51% at a concentration of 500 ppm. Afterward, to evaluate the protective effectiveness of these compounds, gravimetric and electrochemical impedance spectroscopy (EIS) serve as the main methods, accompanied by optical and atomic force microscopy (AFM) for evaluating the surface. In electrochemical tests, PILs 1 and 2 exhibit superior efficiency, with film formation, while PILs 3 to 6 demonstrate comparatively lower values. industrys industry s resistance feasible However risks (PILs A36 (A36 3.5 35 5 (3. wt NaCl, NaCl , NaCl) surface Notably 72 tested scenarios 4 C °C 74 50 100 ppm notably 51 Afterward compounds EIS (EIS methods AFM (AFM tests formation A3 (A3 3. (3 7 10 (A (

This research investigates the effects of accelerated spheroidizing of cementite on the mechanical properties and microstructural characteristics of commercial steel grades (Fe-0.2C, Fe-0.5C, Fe-0.7C wt%), emphasizing the role of cold-rolling reduction followed by stress relief annealing. Utilizing SEM imaging, X-ray diffraction, and EBSD measurements, this study comprehensively examines how variations in carbon content influence hardness, dislocation density, and crystallographic texture orientation. Microhardness measurements reveal a direct relationship with carbon content, yielding values of 28.0±1.0 HRC for DT-1020, 36.0±1.0 HRC for DT-1050, and 39.0±1.0 HRC for DT-1070. Texture analysis through EBSD demonstrates distinct patterns among the grades: DT-1020 displays a dominant (111) texture, DT-1050 exhibits a (101) orientation, and DT-1070 features a more refined (101) texture. Dislocation density analysis further corroborates the impact of carbon content, with DT-1050 presenting the highest density at approximately 7.8×1016 m-2. This detailed exploration elucidates the intricate interplay between carbon content, cementite morphology, and their collective influence on mechanical performance of steel, providing valuable guidance for tailoring steel properties via microstructural control. Fe0.2C, Fe02C FeC Fe 0.2C, 0 2C C (Fe-0.2C Fe0.5C, Fe05C 0.5C, 5C Fe-0.5C Fe0.7C Fe07C 0.7C 7C wt%, wt wt% , wt%) coldrolling cold rolling annealing imaging Xray X ray diffraction hardness orientation 28010 28 1 28.0±1. DT1020, DT1020 DT 1020, 1020 36010 36 36.0±1. DT1050, DT1050 1050, 1050 39010 39 39.0±1. DT1070. DT1070 1070. 1070 DT-102 111 (111 DT-105 101 (101 DT-107 781016 7 8 1016 7.8×101 m2. m2 m 2. 2 m-2 morphology control Fe0 Fe0.2C 02C 0.2C Fe0.5C 05C 0.5C 07C 2801 28.0±1 DT102 102 3601 3 36.0±1 DT105 105 3901 39.0±1 DT107 107 DT-10 11 (11 10 (10 78101 7.8×10 m- 280 28.0± DT10 360 36.0± 390 39.0± DT-1 (1 7810 7.8×1 28.0 DT1 36.0 39.0 DT- ( 781 7.8× 28. 36. 39. 78 7.8 7.

Abstract This work leverages Finite Element (FE) modelling to optimise the deck geometry in continuous composite slab systems, focusing on trapezoidal profile decks. Subsequently, it examines the effectiveness of reinforcing the hogging moment area with Carbon Fiber Reinforced Polymer (CFRP). The main objective is to improve the structural performance when subjected to static loads by optimising geometric factors such as deck height and thickness. The deck profile that yielded the best results had a height of 60 mm, a thickness of 1 mm, and a shear span of 850 mm and resulted in a 7.6% increase in the ultimate load compared to a deck with a thickness of 0.75 mm. The study also assesses the impacts of CFRP reinforcement configurations. The optimal outcome was attained by utilising carbon fiber reinforced polymer (CFRP) sheets that spanned the whole width of the slab for a length of 1.7 m, resulted in a significant 43.17% enhancement in ultimate load. The CFRP enhanced slab, which spans the whole width, demonstrated a maximum load-carrying capability of 176.78 kN. Theoretical analysis indicated a high level of concurrence with FEM. FE (FE systems decks Subsequently CFRP. . 6 85 76 7 7.6 075 0 75 0.7 configurations (CFRP 17 1. m 4317 43 43.17 loadcarrying carrying 17678 176 78 176.7 kN FEM 8 7. 07 0. 431 4 43.1 1767 176. 43.

In this work, electrochemical tests were performed to measure hydrogen permeation during free dissolution of carbon steel in the presence of the ionic liquids (ILs) 1-ethyl-3-methylimidazolium acetate [(EMIM)+(Ac)-], 1-ethyl-3-methylimidazolium bromide [(EMIM)+(Br)-], and 1-butyl-3-methylimidazolium tetrafluoroborate [(BMIM)+(BF4)-] in 5.4 mol L-1 HCl aqueous solution. The permeation inhibition efficiencies (IEp (%)) of 5-hydroxy-2-nitromethylene-hexahydropyrimidine (HPY) and a commercial corrosion inhibitor (CCI) were also evaluated. Among the ILs, the (BMIM)+(BF4)- compound presented the highest corrosion and hydrogen permeation inhibition efficiencies, with values of 23% and 30%, respectively. The (EMIM)+(Br)- and (EMIM)+(Ac)- compounds were not effective against corrosion, but they presented IEp of 15.8% and 23%, respectively. The HPY compound demonstrated 61% effectiveness in preventing corrosion, while in silico evaluation indicated no toxicity. However, neither the HPY compound nor the CCI compound inhibited the entry of hydrogen into the carbon steel during the pickling process. work ILs (ILs 1ethyl3methylimidazolium ethylmethylimidazolium 1 ethyl 3 methylimidazolium EMIM+Ac, EMIMAc EMIM + Ac , [(EMIM)+(Ac)-] EMIM+Br, EMIMBr Br [(EMIM)+(Br)-] 1butyl3methylimidazolium butylmethylimidazolium butyl BMIM+BF4 BMIMBF4 BMIMBF BMIM BF4 BF [(BMIM)+(BF4)- 54 5 4 5. L1 L L- solution % (%) 5hydroxy2nitromethylenehexahydropyrimidine hydroxynitromethylenehexahydropyrimidine hydroxy 2 nitromethylene hexahydropyrimidine (HPY (CCI evaluated (BMIM)+(BF4) 23 30 30% respectively EMIM+Br (EMIM)+(Br) EMIM+Ac (EMIM)+(Ac) 158 15 8 15.8 61 toxicity However process [(EMIM)+(Ac)- [(EMIM)+(Br)- BMIM+BF [(BMIM)+(BF4) (% nitromethylenehexahydropyrimidine (BMIM)+(BF4 (EMIM)+(Br (EMIM)+(Ac 15. 6 [(EMIM)+(Ac) [(EMIM)+(Br) [(BMIM)+(BF4 ( (BMIM)+(BF [(EMIM)+(Ac [(EMIM)+(Br [(BMIM)+(BF

L-histidine was analyzed in this work as a corrosion inhibitor for AISI 1018 carbon steel in chloride solution, without (pH 7) and with carbon dioxide saturation (pH 4). Mass loss methods and electrochemical tests were used. In a medium with pH 4 saturated with CO2, the inhibition efficiency values (IE%) did not reach 34%. For the pH 7 condition, an inhibition efficiency of up to 89% was observed. The values corroborated with the quantum chemistry and Density Functional Theory (DFT) calculations, showing that the histidine molecule is responsible for the excellent inhibition potential. A Fourier transform infrared spectroscopy (FTIR) study and a thermogravimetric study (TGA) of the amino acid were also carried out. The substrate surface was analyzed by scanning electron microscopy and atomic force microscopy. Lhistidine L 101 solution 4. . 4) used CO2 CO IE% IE (IE% 34 34% condition 89 observed DFT (DFT calculations potential FTIR (FTIR TGA (TGA out 10 (IE 3 8 1

RESUMO A fosfatização é um tratamento de superfícies metálicas muito utilizado no meio industrial pois proporciona maior aderência do filme de tinta ao substrato metálico e maior eficiência na inibição da corrosão. Os agentes condicionantes no processo de fosfatização contribuem para a redução do tempo de obtenção da camada de fosfato e favorecem o refinamento dos cristais formados. Comercialmente, o agente condicionante mais utilizado é a base de sais de titânio, no entanto, é possível que outros compostos, possam ser uma alternativa na otimização do processo industrial. Portanto, com o intuito de reduzir o tempo e a temperatura do processo de fosfatização, esse trabalho tem por objetivo verificar o desempenho do uso do agente condicionante a base de fosfato de zinco na obtenção da camada fosfatizada, quanto à resistência à corrosão, em comparação ao condicionador à base de titânio. Para tanto, amostras de aço carbono SAE 1010 foram desengraxadas e jateadas, imersas por 1 minuto na solução condicionante (titânio ou fosfato de zinco) e fosfatizadas com solução comercial de fosfato de zinco tricatiônico em diferentes temperaturas (40 e 50°C) e tempos de imersão (2, 3 e 4 minutos). As massas depositadas dos revestimentos de fosfato foram medidas e os revestimentos caracterizados por microscopia eletrônica de varredura (MEV), por meio de ensaios eletroquímicos de potencial de circuito aberto e polarização potenciodinâmica. Os resultados mostraram que a maior cobertura do substrato, com a formação de camadas mais densas melhora o desempenho anticorrosivo das amostras fosfatizadas com ambos condicionadores. Para o condicionador a base de titânio, as condições ótimas de fosfatização foram de 3 min a 50°C, enquanto para o condicionador de fosfato de zinco, foram de 2 min a 40°C. Portanto, indica-se para uso comercial a imersão em condicionador a base de fosfato de zinco, seguido de fosfatização por 2 min a 40°C. corrosão formados Comercialmente titânio entanto compostos Portanto fosfatizada tanto 101 jateadas 40 (4 50°C 50C C 50 2, (2 minutos. minutos . minutos) MEV, MEV , (MEV) potenciodinâmica condicionadores 40C 40°C indicase indica se 10 ( 5 (MEV

ABSTRACT Phosphating is a metallic surface treatment widely used in the industrial environment as it provides greater adhesion of the paint film to the metallic substrate and greater efficiency in inhibiting corrosion. The conditioning agents in the phosphating process contribute to reducing the time to obtain the phosphate layer and favor the refinement of the formed crystals. Commercially, the most used conditioning agent is based on titanium salts, however, it is possible that other compounds may be an alternative in optimizing the industrial process. Therefore, with the aim of reducing the time and temperature of the phosphating process, this work aims to verify the performance of using the conditioning agent based on zinc phosphate in obtaining the phosphatized layer, in terms of corrosion resistance, in comparison with to the titanium-based conditioner. For this purpose, SAE 1010 carbon steel samples were degreased and sandblasted, immersed for 1 minute in the conditioning solution (titanium or zinc phosphate) and phosphated with a commercial solution of tricationic zinc phosphate at different temperatures (40 and 50°C) and immersion times (2, 3 and 4 minutes). The deposited masses of the phosphate coatings were measured and the coatings characterized by scanning electron microscopy (SEM), through electrochemical tests of open circuit potential and potentiodynamic polarization. The results showed that the greater coverage of the substrate, with the formation of denser layers, improves the anticorrosive performance of samples phosphated with both conditioners. For the titanium-based conditioner, the optimal phosphating conditions were 3 min at 50°C, while for the zinc phosphate conditioner, they were 2 min at 40°C. Therefore, for commercial use, immersion in a zinc phosphate-based conditioner is indicated, followed by phosphating for 2 min at 40°C. crystals Commercially salts however Therefore resistance titaniumbased purpose 101 sandblasted 40 (4 50°C 50C C 50 2, (2 minutes. minutes . minutes) SEM, SEM , (SEM) polarization layers conditioners 40C 40°C use phosphatebased indicated 10 ( 5 (SEM

The present study aimed to develop and characterize super-hydrophobic nickel coatings through the electrodeposition process, employing myristic acid as a surface energy reducing agent, with the objective of enhancing corrosion resistance. ASTM A36 carbon steel (E00) specimens served as substrates for the application of three different coating conditions: pure nickel (E10); nickel associated with myristic acid (E01); and a bilayer structure consisting of a base layer of pure nickel succeeded by an additional layer of nickel enriched with myristic acid (E11). The samples were characterized through Optical Microscopy (OM), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), X-ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR). Corrosion resistance of the coatings was analyzed through potentiodynamic polarization (PP) tests and electrochemical impedance spectroscopy (EIS). XRD and FTIR tests confirmed the deposition of metallic nickel onto the substrate and the successful incorporation of the surface energy reducing agent. Micrographs illustrated the distinctive cauliflower-like clusters in the E11 coating, denoting its pronounced super-hydrophobic characteristics, culminating in a contact angle of 165º. Corrosion tests demonstrated superior anticorrosive behavior in the E11 sample, as evidenced by a heightened corrosion potential, diminished anodic current density, and an augmented impedance modulus. The results emphasize the role of superhydrophobicity in influencing the corrosion resistance of the developed coatings. superhydrophobic super hydrophobic process agent A A3 E00 E (E00 conditions E10 (E10) E01 (E01) E11. . (E11) OM, OM , (OM) SEM, SEM (SEM) EDS, EDS (EDS) Xray X ray XRD, (XRD) FTIR. (FTIR) PP (PP EIS. EIS (EIS) cauliflowerlike cauliflower like E1 characteristics 165º º sample potential density modulus E0 (E0 (E10 (E01 (E11 (OM (SEM (EDS (XRD (FTIR (EIS (E (E1

Guanine was investigated as a potential green corrosion inhibitor to API 5L X65 carbon steel in HCl 0.1 mol.dm-3 solution, at pH = 2.0, under hydrodynamic conditions using electrochemical, weight loss and Raman spectroscopy experiments. Cyclic voltammetry and potentiodynamic polarization curves suggested that Guanine does not change the metal/solution interface appreciably and weight loss tests confirmed the low inhibition efficiency (IE) of Guanine in protecting the X65 steel in this corrosive medium. An IE = 22% was determined after 48 h of exposure, a value lower than that reported in the literature on the mild steel/Guanine/HCl system. Raman spectroscopy was employed to gain insight on the nature of the steel/Guanine interaction and the results pointed out to a weak physisorption of the molecule, thus explaining the very low IE values obtained. L X X6 01 0 1 0. mol.dm3 moldm3 moldm mol.dm 3 mol dm mol.dm- solution 20 2 2.0 electrochemical experiments metalsolution metal (IE medium 22 4 exposure steelGuanineHCl system steelGuanine molecule obtained dm3 2.