XC48 Steel Research Articles

Determining boride layer thicknesses formed on XC38 steel with artificial neural network

Determining boride layer thicknesses formed on XC38 steel with artificial neural network

Unlocking the power of Inula Viscosa essential oil: A green solution for corrosion inhibition in XC48 steel within acidic environments

A sustainable corrosion inhibitor for XC48 steel in a 1 M HCl environment was effectively formulated using the essential oil of Inula viscosa (IVEO), as corroborated by gas chromatography-mass spectrometry (GC-MS) results. This novel application was assessed via multiple techniques: mass loss, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), Fourier-transform infrared spectroscopy with an attenuated total reflectance accessory (FT-IR/ATR), X-ray diffraction (XRD) and scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS) and Atomic Force Microscopy (AFM) for surface examination. The plant extract’s inhibitory capacity raised in proportion to its concentration, as confirmed by both mass loss and electrochemical investigations. This trend reached a high point at a 97% inhibitory efficiency at a concentration of 400 ppm at 298 K. FTIR, XRD, SEM/EDS, and AFM analyses further validated the binding of this eco-friendly inhibitor onto the steel surface, which exhibited mixed-type characteristics, thus elucidating its exceptional inhibitory performance. The Langmuir isotherm model aptly fitted the adsorption analysis, indicating the development of an organic protective layer. Advances computational calculations of various quantum chemical parameters for the key ingredients of the essential oil added to the understanding of the link between adsorption and corrosion inhibition.

Confrontation of linear versus nonlinear approach in Fe2B boridelayer thickness predictions

Kinetic studies of boride layers focus on trying to accurately predict their thicknesses according to some variables using different approaches. In this paper, an approach that is reliant on a multilinear regression is investigated. In doing so, with an engineering perspective, temperature and time are used as the sole variables in predicting a boride layer thickness u. The approach uses experimental data from a boriding process performed on iron substrates of the XC38 steel. A comparison between the proposed linear model and a nonlinear one is seen afterward to scrutinize the results. That nonlinear approach is known as the diffusion model and is based on Fick’s second law, where it uses more variables than the linear approach to estimate its predictions. Ultimately, the comparison elucidated that the use of a linear regression-based model can be an accurate engineering tool to identify boride layer thicknesses, but without interpolating the results outside the scope of the studied interval.

Experimental and DFT studies of a novel salicylhydrazone derivative as a steel corrosion inhibitor

The inhibitory properties of a newly synthesized salicylhydrazone derivative, namely 2-hydroxybenzaldehyde {(1E)-[4-(dimethylamino)phenyl]methylene}hydrazine (HBMH), towards the corrosion of XC38 carbon steel in 1 M hydrochloric acid, has been studied using weight loss, electrochemical measurements and theoretical calculations. Gravimetric results have shown that the inhibition efficiency of this compound increases with its concentration and decreases with temperature to reach a maximum of 90% at 293 K in the presence of 10−3 M of this inhibitor. Potentiodynamic polarization measurements have revealed that this salicylhydrazone is of mixed-type since it exhibits both anodic and cathodic corrosion inhibition performance. This inhibitor adsorbs and forms a protective barrier on the metal surface by a simple geometrical blocking of the active sites of this surface. Its adsorption proceeds essentially via physisorption mode and obeys the Langmuir's isotherm model. The density functional theory (DFT) calculations revealed the HBMH’s electron donor-acceptor nature, which may facilitate its adsorption on the XC38 steel surface.

Corrosion inhibition of XC48 steel by Grewia bicolor jus leaves extract in 1M HCL acid medium: electrochemical and gravimetric study

Corrosion inhibition of XC48 steel by Grewia bicolor jus leaves extract in 1M HCL acid medium: electrochemical and gravimetric study

Experimental and detailed DFT/MD simulation of α-aminophosphonates as promising corrosion inhibitor for XC48 carbon steel in HCl environment

BackgroundCorrosion is a pervasive issue in several industries, causing safety hazards and substantial economic losses. α-aminophosphonate substances have recently garnered attention for their ability to inhibit corrosion. In this study, two specific α-aminophosphonate molecules, namely diethyl(furan-2-yl(phenylamino)methyl) phosphonate (AMP1) and diethyl((2methoxyphenyl) amino) (thiophene-2-methyl) phosphonate (AMP2) were evaluated for their potential as anticorrosion agents for XC48 carbon steel under acidic conditions. MethodsTheir corrosion inhibition was examined towards XC48 carbon steel under 1.0 M HCl solution utilizing the electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), atomic force microscope (AFM), scanning electron microscope (SEM), contact angle, Density functional theory (DFT), molecular dynamics (MD), and atoms in molecule (AIM). Significant findingsResults showed that AMP1 and AMP2 had inhibition efficiencies of 83.34% and 63.82% for EIS and 82.70% and 74.57% for PDP, respectively. The inhibition mechanism involved adsorption of the additives onto the metal surface via Langmuir isotherm. The study also demonstrated the influence of temperature on inhibition efficiency, with nearly 70% inhibition observed at 298 to 323 K. AFM and SEM analyses revealed chemisorption coating formation inhibiting acid attack, and contact angle analyses showed the surface to be hydrophobic. Theoretical analyses using DFT, MD, and AIM were used to clarify the inhibitors' adsorption effect on XC48 steel, showing a high agreement with experimental findings.

Comparative study of inhibitory efficacy of drug (Acetaminophen) in 1 M HCl medium applied to carbon and mild steels

Metals and alloys differ from other materials in a number of advantageous properties, but they have disadvantages because of their instability in contact with certain media. This leads to a decrease in their corrosion resistance, the costs of which are enormous, especially in industrialized countries. These costs could be higher without corrosion protection. The durability of steel structures depends mainly on their corrosion resistance. The protection technique of adding corrosion inhibitors Acetaminophen (A1) was studied using low and high carbon steels (mild and XC48 steels). This work was conducted by gravimetric and electrochemical measurements (current–voltage stationary curves). Acetaminophen (A1) inhibited both corrosion of XC48 steel and mild steel in HCl solution (1 M). The results show that the products work as inhibitors for both steels and the inhibition efficiencies at the concentration of 5 × 10-3(M) are interesting. This inhibitor adsorbs to the surface of both metal XC48 and mild steel MS. The effect of chemical composition of steel was also discussed.

Monte Carlo simulation and electrochemical performance corrosion inhibition whid benzimidazole derivative for XC48 steel in 0.5 M H2SO4 and 1.0 M HCl solutions

The inhibition of 1-(4-methoxybenzyl)-2-(4-methoxyphenyl)-1H-benzimidazole (MMB) on corrosion of XC48 steel in solutions 1.0 M HCl and 0.5 M H2SO4 were studied by potentiodynamic polarization and electrochemical impedance spectroscopy techniques (EIS). Potentiodynmic polarization curves revealed that MMB acts as a mixed-type inhibitor in both acidic media. The impedance results indicated that the corrosion process occurs under activation control. Furthermore, MMB shows a higher inhibition efficiency in HCl (97%) than in H2SO4 (92%) at 10−4 M MMB. The values of ΔG°ads, ΔHa, Ea and ΔSa in temperature range 293–323 K indicated that MMB strongly retarded the corrosion of XC48 steel in both solutions by a chemisorptions process. The adsorption of Benzimidazole (MMB) on carbon steel surface followed Langmuir adsorption isotherm. Scanning electron microscopy (SEM) analysis confirmed that there is an adsorbed film on the surface of XC48 steel. The results of Monte Carlo simulations studies confirmed the inhibition action of MMB.

Electrochemical study and experimental simulation of the synergistic effect of a formulation based on Ficus pumila Linn. Leaves extract and zinc sulfate on the XC38 steel corrosion inhibition in NaCl solution

The inhibitive activity of a mixture of Ficus pumila Linn. leaves hydroalcoholic extracts (HEFP) and zinc ions against corrosion of XC38 steel in NaCl solution was investigated. Electrochemical measurements (potentiodynamic polarization and electrochemical impedance spectroscopy at and around the corrosion potential) and surface analysis (SEM/EDX) have shown that the presence of zinc ions considerably increases the inhibitive capacity of HEFP. However, appropriate concentrations of zinc ions (50 and 100 ppm) and of HEFP (200 ppm) are necessary to have an optimal inhibitive effect. The formation of organometallic complexes between zinc ions and some organic compounds of HEFP (polyphenols and carbohydrates) are the determining step of the synergistic inhibition. Since the main inhibitive agents in plant extracts are polyphenols, a simulation of this inhibitive character was electrochemically done with a mixture of flavonoid (quercetin), phenolic acid (gallic acid) and zinc ions in order to elucidate the inhibition mechanism. The obtained results showed that the electrochemical behavior of XC38 steel in the presence of this mixture is quite similar to that obtained in the presence of HEFP + Zn2+ formulation. The proposed inhibition mechanism, which explains the good inhibitive efficiency observed in presence of the HEFP + Zn2+ formulation, is based on concerted reactions between the steel oxidation products (Fe2+ and Fe3+), the zinc ions and the Iron(II) and Iron(III) complexing agents present in the extract.

Impact of the diffusion coefficient calculation on predicting Fe2B boride layer thickness

Abstract In this study, a single-phase boride layer thickness Fe2B is predicted on two different substrates (Armco iron and XC38 steel) by following the integral method. This method is a mathematical model based on a system of differential algebraic equations that help to deduce the diffusion coefficient, which is the key factor on predicting the layer thickness. Literatures cover different diffusion coefficients for each substrate, albeit researchers usually extract from experimental data, variations of growth rate constants within only one time treatment and deduce the diffusion coefficient from them. This deduction is done via an estimation of a frequency factor and an activation energy from the growth rate constants. Therefore, our main aim is to illustrate the impact of the deduction of the diffusion coefficient on predicting the boride layer thickness. Lastly, the impact with and without incubation time on the boriding kinetics of both substrates was also examined.

Comparison between Lacunary and Saturated Keggin Polyoxometalates as Steel Corrosion Inhibitors in Chloride Solution: Contribution of the Lacuna in the Inhibition Mechanism

AbstractThe effect of two lacunary Keggin polyoxometalates (K7[PW11O39].14H2O and K9[AlW11O39].15H2O) on the corrosion inhibition of XC38 steel in 0.1 M NaCl was investigated. Electrochemical methods (polarization curves and electrochemical impedance spectroscopy) showed that the presence of controlled amounts of these compounds improved protection of the steel against corrosion. These results were supported by surface analysis, where only a minor amount of rust was produced on metal surface in the presence of polyoxometalates (POMs). The lacunary POMs were more efficient compared to their saturated species, highlighting the key role played by the lacuna on the inhibition process. Efficiency of POMs (both saturated and lacunary) was explained by their ability to increase the Fe(II)/Fe(III) molar ratio in greenish protective oxide layer formed upon steel oxidation. The mechanism proposed clearly explains the higher efficiency observed with lacunary POMs, in relation to their ability to react with free Fe(III) to yield a substituted structure.

Paste Borided Layers Produced on XC38 Steel Using a New Activator

Abstract The objective of this work is to study the possibility of producing boride layers on XC38 steel by the slurry coatings technique in a muffle furnace under an ambient atmosphere. The principle of this technique consists in the application of a slurry of about 1–2 mm thickness containing boron carbide as a boron source and sodium fluoroborate (NaBF4) as a new activator on the surface of the sample to be treated and placed in a muffle furnace at 800°C for 4 hours. The obtained results show that it is possible to produce boride layers on XC38 steel by the slurry coatings technique with NaBF4 as an activator. The characterization of the obtained layers by Optical Microscopy, Scaning Electron Microscope (SEM), X-Ray Diffraction (XRD), and microhardness indicates that depending on the proportion of the boron source and the activator, these layers can be single phase (only di-iron boride [Fe2B]) at 10 % of NaBF4 or two phases iron monoboride (FeB) and Fe2B when the proportion of NaBF4 exceeds 10 %. The total thickness of the obtained boride layers is approximately 60 μm for all the slurries’ composition. But it should be pointed out that for the two-phase borided layers, the proportion of FeB boride increases with the increase of the percentage of NaBF4. The microhardness of borided layers is relatively similar for all samples and about 2,100 HV for FeB boride and 1,900 HV for Fe2B.

Computational and experimental studies on the efficiency of Rosmarinus officinalis polyphenols as green corrosion inhibitors for XC48 steel in acidic medium

The performances of the extract obtained from Rosmarinus officinalis (RO) on the corrosion inhibition of XC48 steel is examined by mass loss method, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), potentiodynamic polarization (PDP), Fourier transform infrared (FTIR) spectroscopy and liquid chromatography–mass spectrometry (LC–MS). Investigations are performed in hydrochloric acid solution at 1 M concentration at different temperatures. Results show that the RO extract behaves as an inhibitor of mixed-type; in particular, the inhibition efficiency is augmented at greater concentration of the inhibitor and decreases with the rise of the temperature from 303 K to 333 K. The values of activation and free energy of inhibition reaction support the hypothesis of a mechanism of physisorption that is adequately described by the Langmuir equilibrium model. The retrieved outcomes are confirmed by SEM observations, which reveal that the adsorbed inhibitor molecules completely hinder the HCl attacks at the steel grain boundaries. Finally, quantum chemical calculations show that among the most abundant component detected in the RO extract, carnosic acid has a greater inhibitor potential with respect to carnosol.

Solvent and catalyst-free synthesis, corrosion protection, thermodynamic, MDS and DFT calculation of two environmentally friendly inhibitors: Bis-phosphonic acids

Solvent and catalyst-free synthesis of two bis-phosphonic acids were realized adopting one-pot reaction of 2,6-bis (hydroxymethyl)-4-methoxyphenol or 4-chloro- 2,6-bis (hydroxymethyl) phenol with trialkyl phosphite. Their structures were confirmed by 1H, 13C, 31P NMR and IR spectroscopies. The molecular structures have been optimized using DFT, and the related calculated vibrational frequencies and NMR shift confirm the proposed structures. Chemical and electrochemical tests evaluated the inhibitive capabilities on the XC48 steel corrosion against 1 M HCl. The weight loss (chemical one) shows that the adsorption on the XC48 steel surface obeys to Langmuir isotherm, while the polarization measurements suggest that the inhibition process is mixt, the results of Electrochemical Impedance Spectroscopy (EIS) prove an increase of the inhibition efficiency with the increase of inhibitor concentrations. The surface topographies were analyzed by the Atomic Force Microscopy (AFM). The Density Functional Theory (DFT) with B3LYP as correlation function and 6-31G (p, d) as basis sets were used to determine some theoretical physic-chemical parameters affecting the corrosion inhibition and on the other hand the DFT develop the Frontier Molecular Orbitals (FMOs) and the Molecular Electrostatic Potentials (MEP) and through a discussion was made about their relationship with the inhibition of the corrosion. At the end, Molecular Dynamics Simulations (MDS) based on Monte-Carlo calculations were accomplished to simulate the interface configuration between the inhibitor molecules and Fe (110)/H2O.

Fuzzy logic approach for modelling the formation kinetics of Fe<SUB align="right">2B layer

In this article, a method for the modelling and simulation of a thermochemical boronising process was proposed. This diffusion model using the artificial intelligence technique represented by the fuzzy logic (FL) approach is mainly based on a number of assumptions and kinetic data. To demonstrate the validity of our calculations, we compared the FL simulation results with experimental data from the boronising treatment of XC38 steel in molten salts containing borax. The comparison of the results derived from the fuzzy logic model with those obtained experimentally allowed us to verify the validity of the model that yields very interesting results. Therefore, this approach can be considered as a modelling tool when parameters and data used by classic mathematical models are not available or difficult to obtain. The error obtained using the FL model is nearly to 1.2%. This relatively simplistic approach is a useful and a predictive tool for the boronising process.

Heat treatment effect on the microstructural, hardness and thermal properties of XC48 steel

This work examines the effect of heat treatment parameters such as the cooling velocity and the quenching fluid nature on the structural, Rockwell hardness and thermal properties of XC48 steel. The studied specimen is a cylinder of 3 cm diameter and 10 cm length, and the used quenching fluids are oil, water and air. The investigation shows that the XC48 hardness varies from 18 to 58 HRC through the used quenching fluid and decreases along the length of the specimen contrary to the thermal conductivity and thermal diffusivity, which are primarily in the order of 36 W m−1 K−1 and 0.125 cm2 s−1 respectively, and which increase with the quenching velocity. A correlation between these thermo-mechanical properties such as the hardness and the thermal conductivity is realized to obtain a new nondestructive technique permitting to determine the mechanical hardness without measuring it. This technique is of an overwhelming importance and can be used in the industrial and research fields.

Synthesis, spectral analysis, theoretical studies, molecular dynamic simulation and comparison of anticorrosive activity of an ester and an acid α-Hydroxyphosphonates

Diethyl [hydroxy (phenyl) methyl] phosphonate ester (DHPMP) and [hydroxy (phenyl) methyl] phosphonate acid (HPMPA) have been synthetized and their structures were confirmed by IR, UV–Vis, 1H, 13C and 31P NMR spectroscopies. Their inhibitive capacities on the XC48 steel corrosion in 1M HCl has been determined by chemical and electrochemical measurement, the weight loss proves that the adsorption of the ester or the acid on the surface of XC48 steel obeys to Langmuir isotherm, while the polarization measurements indicate that the inhibition process is mixt, finally, Electrochemical Impedance Spectroscopy (EIS) results show that the inhibition efficiency increased with increasing the inhibitors concentrations. Surface topographies were carried out using the Atomic Force Microscopy (AFM). The Density Functional Theory (DFT) using (B3LYP) method with 6-31G (p, d) basis sets was performed to calculate some thermodynamic parameters influencing the corrosion inhibition effect. Also, the Molecular Dynamics Simulations (MDS) was performed to simulate the interface configuration between the inhibitors molecules and Fe (100)/H2O or Fe2O3 (110)/H2O.

Effect of heat treatment on surface hardness and tribological behavior of XC38 steel—approach by the experiments plans

This work aims at predicting the micro-hardness of XC38 steel using the experiments plans as well as study of tribological behavior of this steel. The heat treatments were considered by adopting the factorial plans 22 methodology at two factors (temperature ‘T’ and holding time ‘t’), each at two levels (−1, +1). The results obtained allowed lead to a mathematical model predicting the micro-hardness ‘Hv’ in every point of the study field. Moreover, the curves of the responses surfaces clearly show the influence of two factors studied (T, t) on ‘Hv’. Mechanical characterization of treated samples showed a significant increase in the micro-hardness, which achieve to 76% for the treated sample at 850 °C during 2 h compared to untreated state. An investigation of wear tracks morphology shows that friction under a load of 10 N results in predominant adhesive wear, while a load of 2 N favor abrasive wear.

Effects of work hardening on mechanical metal properties—experimental analysis and simulation by experiments

The aim of the present work is to improve the materials’ performances, particularly their elastic property based on an optimal exploitation of surface work-hardening phenomenon, using surface plastic deformation treatment (DPS). The surface of a mechanical piece is considered as the most vulnerable zone that determines its mechanical performances. To improve the surface physico-mechanical properties, the surface plastic deformation treatment (DPS) is often used. The (DPS) acts by a combined action of: surface hardening, structural modification, and the generation of the compression residual stresses, the factors that will create a heterogeneous plastic deformation. Knowing that during operation the mechanical pieces have to be subjected to a stress smaller than the elastic limit (taking into account the safety margins), where the material behavior is reversible, and to reach the maximum allowable stresses, we have to increase the material’s elastic limits. This objective can be realized through an optimal use of work hardening phenomenon for the treated surface by the DPS. The work hardening is characterized by the increase of the yield strength (Re), the surface hardness (Hv), and consequently the increase of the brittleness. Depending on the considered metals, when the piece has a defect variation: cavity, inclusion (precipitate), or zones of different hardness, it can create a stress concentration which generates a local hardening. This phenomenon is one of the main causes of crack generation. In our study, we consider the influence of work hardening on the elastic behavior of XC38 steel and aluminum alloy.

Effect of Boride Incubation Time During the Formation of Fe2B Phase

Our present study focuses on the numerical simulation of the boronized layer growth kinetics on the iron substrate of the XC38 steel, the boronizing treatment is performed in a liquid medium composed of borax and silicon carbide. We mainly calculated the incubation time of the boronized layer formation. Aimed at estimating the boronizing treatment kinetics of XC38 steel, we initially used experimental data. The study was conducted to determine the law of borided layers growth and estimate the boron diffusion coefficient in the Fe2B layer. The diffusion coefficient obtained from this experiment is: D Fe 2 B = 1 . 388 × 10 − 4 exp − 207 . 8 × 10 3 j RT m 2 s − 1 In order to calculate the incubation time of the Fe2B layer, we adapted the mathematical model, which is based on the second law of Fick. This model takes into account the thermodynamic properties of the Fe-B phase diagram. The comparison of the results obtained by the simulation with those obtained experimentally verifies the validity of the theoretical study and a good agreement was obtained as well.