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This paper aims to clarify the corrosion behavior of two famous structural steels in sour environment. These steels have a vast application in oil and gas industries. The study aims to find the effect of different concentrations of sour solution on the origin of crack in these steels.

After preparation of specimens, different sour solutions were made using the synthetic brine (according to National Association of Corrosion Engineers [NACE], Technical Committee Report 1D182) and various amounts of Na₂S.9H₂O and CH₃COOH. The polarization test was done by Potansiostat apparatus model Zahner-IM6 at two temperatures, 25°C and 50°C. The corrosion current densities were obtained from the polarization curves. Finally, the corrosion products and hydrogen-induced cracking (HIC) were investigated by Tescan Vega II XMU scanning electron microscope (SEM) linked to a Rontec energy-dispersive X-ray spectroscopy (EDS) system.

API 5L-X70 steel showed smaller corrosion current values than A516-Gr70 steel. The HIC cracks propagated parallel to the surface of A516-Gr70 steel in three solutions and confirmed the inappropriateness of this steel for sour environment applications.

This paper studies the effect of sour environment on the behavior of two famous industrial steels at two temperatures by new method.

The purpose of this paper is to obtain iron‐enriched Fe‐Ni alloy foil on Ti substrates with good quality from a chloride‐sulfate bath used in a normal DC plating mode. The effects of iron content on the hardness, surface morphology and microstructure of the foil were clarified.

Fe‐Ni alloy foil was prepared by electrodeposition in a chloride‐sulfate based solution. The effects of current density, temperature, stirring rate and sodium propargyl sulfonate concentration on the iron contents of the Fe‐Ni alloy foils were studied. The phase composition and surface morphology with various iron contents were characterized by X‐ray diffraction (XRD) and atomic force microscopy (AFM), respectively. Cathodic polarization curves were used to evaluate the role of sodium propargyl sulfonate (PS).

Nanocrystalline Fe‐Ni alloy foil containing up to 64 wt. percent iron can be obtained from a chloride‐sulfate based solution. The foil converts from a face‐centered cubic (fcc) Fe3Ni2 phase to a mixture of fcc and body‐centered cubic (bcc) Fe7Ni3 with increase in iron content from 55.0 wt. percent to 63.5 wt. percent. AFM studies revealed that the foil had a fine grain structure with a roughness of 30 nm and grain size of 30 nm. With iron increasing to 63.5 wt. percent some islands appeared on the surface. This structure was related to the development of a (200) fiber texture in the BCC phase. Sodium propargyl sulfonate accelerates the discharge of nickel and inhibits the discharge of Fe.

The foil has many industrial applications in the area of memory devices for computers, laser components and precise instruments.

The paper presents a process to produce a foil with iron up to 64 wt. percent from a chloride‐sulfate based solution used in normal DC mode. The dependence of microstructure and surface morphology on iron contents also is presented. Until now, there has been little research or reports on this subject.

This paper aims to investigate the experimental behavior and the reliability of concrete columns repaired using fiber-reinforced polymers (FRPs) under axial compression loading. The expression of the ultimate axial resistance was assessed from the experimental data of damaged concrete cylinders repaired by externally bonded double-FRP spiral strips.

The tested columns bearing capacity mainly depends of the elasticity modulus of both damaged and undamaged concrete have been considered in addition to the applied load and the cylinder diameter as random variables in the expression of the failure criterion. The reliability indicators were assessed using first order second moment method.

The emphasized test results, statistically fitted show that the strength has been retrofitted for all repaired specimens whatever the degree of initial damage. However, the gain in axial strength is inversely proportional to the degree of damage.

The efficiency of a new FRP repair procedure using double-spiral strips was studied. This research provides a technical and economical solution for retrofitting existing concrete columns. Finally, the random character of the variables that govern the studied system shows the accuracy and safety of the proposed original design.

The purpose of this paper is to investigate the corrosion resistance and the electrodeposition behavior of electrodeposited nickel‐cobalt‐iron alloys. Also, to compare the electrodeposition of ternary nickel‐cobalt‐iron alloy from acidic sulfate bath onto a steel substrate with the characteristics of Co‐Fe electrodeposits.

The investigation of electrodeposition was carried out using cyclic voltammetry and galvanostatic techniques, while potentiodynamic polarization resistance and anodic linear sweep voltammetry techniques were used for corrosion study. The phase structure was characterized by means of X‐ray diffraction analysis. The surface morphology and chemical composition of the deposits were examined by using scanning electron microscopy and atomic absorption spectroscopy, respectively.

The obtained results revealed that the Ni‐Co‐Fe alloys consisted of a mixture of iron (Fe10.8Ni) and (FeCo) phases. It was found that the obtained Ni‐Co‐Fe alloy exhibited a more‐preferred surface appearance and better corrosion resistance, compared to the Co‐Fe alloy that was electrodeposited under similar conditions.

Ni‐Co‐Fe alloy was successfully electroplated from a sulfate bath. This alloy showed better anticorrosion properties compared to Co‐Fe deposits. The Ni‐Co‐Fe alloy could be used advantageously in industry, e.g. the automotive industry. The coating also has particular interest due to it is ability to exhibit stable magnetic properties.

The paper evaluates the effect of electrodeposition of the ternary alloy on the corrosion behavior of electroplated steel. To date, there has been little research on this issue. It was found that the presence of Ni could increase the corrosion resistance of steel.

This study aims to investigate the effect of copper and titanium micropowder addition on the mechanical and metallurgical properties of additively manufactured low-carbon steel, aiming to produce a modified (multiphase) steel with ferritic low-carbon steel using in situ micropowder addition during wire arc direct energy deposition (WA-DED).

A robotic arm equipped with a GMA welding source deposited ER70S6 filler wire on AISI S235 substrate steel using WA-DED. Cu and Ti micropowders were interspersed between layers for microstructural modifications. Microscopy, spectroscopy, diffraction and mechanical testing were used to evaluate the properties of the deposited samples.

Incorporating Cu and Ti micropowders significantly enhanced the yield and tensile strength of the deposited material, showing an 83% increase in yield strength and a 33% increase in tensile strength. Microstructural analysis identified key phases such as ferrite, pearlite, bainite, retained austenite and martensite/austenite, with Cu and Ti acting as grain refiners. Nanoscaled Cu precipitates contribute to enhanced low-temperature toughness and a 150% improvement in impact strength at −30°C.

This study presents a novel approach to overcome the limitations of the available alloys (filler materials). This can be achieved by introducing in situ micropowder alloying during the WA-DED process. The micropowder addition allows altering the properties of the deposited material without changing the parent filler material itself, achieving the desired composition. With this approach, there is no need to manufacture the filler material with the preferred alloy composition separately and then carry out the deposition process.

The purpose of this study is to characterize the galvanic corrosion behavior of a simulated X80 pipeline steel welded joint (PSWJ) reconstructed by the wire beam electrode (WBE) and numerical simulation methods.

The galvanic corrosion of an X80 PSWJ was studied using WBE and numerical simulation methods. The microstructures of the coarse-grained heat affected zone, fine-grained heat affected zone and intercritical heat affected zone were simulated in X80 pipeline steel via Gleeble thermomechanical simulation processing.

Comparing the corrosion current density of coupled and isolated weld metal (WM), base metal (BM) and heat-affected zone (HAZ), the coupled WM exhibited a higher corrosion current density than isolated WM; the coupled BM and HAZ exhibited lower corrosion current densities than isolated BM and HAZ. The results exhibited that the maximum anodic galvanic current fitted the Gumbel distribution. Moreover, the numerical simulation results agreed well with the experimental data.

This study provides insight into corrosion evaluation of heterogeneous welded joints by a combination of experiment and simulation. The method of reconstruction of the welded joint has been proven to be a feasible approach for studying the corrosion behavior of the X80 PSWJ with high spatial resolution.

This paper aims to investigate the responses of single piles and pile groups due to tunneling-induced ground movements in a two-layered soil system. The analyses mainly focus on the additional single pile responses in terms of bending moment, lateral deflection, axial force, shaft resistance and pile settlement. Subsequently, a series of parametric studies were carried out to better understand the responses of single piles induced by tunneling. To give further understanding regarding the pile groups, a 2 × 2 pile group with two different pile head conditions, namely, free and capped, was considered.

Using the PLAXIS three-dimensional (3D) software, a full 3D numerical modeling is performed to investigate the effects of ground movements caused by tunneling on adjacent pile foundations. The numerical model was validated using centrifuge test data found in the literature. The relevance of the 3D model is also judged by comparison with the 2D plane strain model using the PLAXIS 2D code.

The numerical test results reveal that tunneling induces significant displacements and internal forces in nearby piles. The magnitude and distribution of internal forces depend mainly on the position of the pile toe relative to the tunnel depth and the distance between the pile and the vertical axis of the tunnel. As the volume loss increases from 1% to 3%, the apparent loss of pile capacity increases from 11% to 20%. By increasing the pile length from 0.5 to 1.5 times, the tunnel depth, the maximum pile settlement and lateral deflection decrease by about 63% and 18%, respectively. On the other hand, the maximum bending moment and axial load increase by about 7 and 13 times, respectively. When the pile is located at a distance of 2.5 times the tunnel diameter (Dt), the additional pile responses become insignificant. It was found that an increase in tunnel depth from 1.5Dt to 2.5Dt (with a pile length of 3Dt) increases the maximum lateral deflection by about 420%. Regarding the interaction between tunneling and group of piles, a positive group effect was observed with a significant reduction of the internal forces in rear piles. The maximum bending moment of the front piles was found to be higher than that of the rear piles by about 47%.

Soil is a complex material that shows differently in primary loading, unloading and reloading with stress-dependent stiffness. This general behavior was not possibly being accounted for in simple elastic perfectly plastic Mohr–Coulomb model which is often used to predict the behavior of soils. Thus, in the present study, the more advanced hardening soil model with small-strain stiffness (HSsmall) is used to model the non-linear stress–strain soil behavior. Moreover, unlike previous studies THAT are usually based on the assumption that the soil is homogeneous and using numerical methods by decoupled loadings under plane strain conditions; in this study, the pile responses have been exhaustively investigated in a two-layered soil system using a fully coupled 3D numerical analysis that takes into account the real interactions between tunneling and pile foundations. The paper presents a distinctive set of findings and insights that provide valuable guidance for the design and construction of shield tunnels passing through pile foundations.

The purpose of this paper is to study the effect of chromium content on the microstructure and corrosion resistance of Ni-Cr coating.

Ni-Cr coating was prepared by pulse current electrodeposition with trivalent chromium. On the basis of studying effect of electroplating parameters on composition and morphology, Ni-Cr alloy coatings with various chromium contents were obtained. The microstructure was characterized by scanning electron microscopy, X-ray diffractometer and transmission electron microscopy. Corrosion behavior was studied by potentiodynamic polarization and electrochemical impedance spectroscopy techniques.

Electrodeposited chromium was solidly dissolved in nickel and refined the grain of the coating. With the increase of Cr content, the corrosion resistance of Ni-Cr coating was enhanced, which is due to the formation of continuous nickel hydroxide and compact chromium oxide passive films.

Ni-Cr alloy coating without penetration crack was prepared in trivalent chromium electrolyte, and the mechanism of its excellent corrosion resistance was proposed.

Key enabling technologies (KETs) are a set of six technological components that work together to address social challenges and build advanced for sustainable economies. Industry 5.0, the next industrial development, is designed to capitalize on specialists' unique creativity while also collaborating with powerful, intelligent, and precise technologies. Industry 5.0 outsourced repetitive and monotonous activities to robots/machines requiring employees to perform activities that involve critical thinking and are based on the 6R (Recognize, Reconsider, Realize, Reduce, Reuse, and Recycle), to improve production quality. With numerous supporting technical advancements, advanced and quick manufacturing concentrating on the interaction of machines and humans may be produced. Maintaining healthcare and nursing care, evaluating patients' health requirements using KETs, and giving care with manpower are all major advancements in Industry 5.0 today. Future studies may focus on providing healthcare using mainly technology and, therefore, no human workers. This chapter highlights healthcare advances in Industry 5.0, where KETs and people collaborate to create and innovate. In this framework, the purpose of this chapter is to present the deployment of KETs in the nursing patient care process.

The adoption of an entrepreneurial posture supports higher education institutions (HEIs) in their quest for growth. The present study examines the role faculty members play in adopting an entrepreneurial orientation (EO) in HEIs within the Kuwaiti academic context and aims to assess whether this orientation contributes to fostering corporate entrepreneurship in their institutions.

Primary data were collected to study the relationship between faculty EO and the EO of their respective HEI. Empirical research was conducted based on a questionnaire completed by 341 engineering and business faculty members employed at Kuwaiti universities and colleges. The research model was tested and validated using structural equation modelling (SEM).

The results show a positive relationship between the faculty EO and corporate entrepreneurship in HEIs, which was negatively moderated by human resource management (HRM) practices. These findings emphasise the need for HEIs in Kuwait to evolve their HRM practices towards enhancing innovation, proactiveness and risk-taking amongst faculty.

This study highlights the strategic renewal perspective in HEI-EO and how faculty initiatives can support it.