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In recent times, among all the substrates used in microfluidic systems, cellulose paper is used as a handy, low-cost substrate that has gained attention for carrying fluid on its surface over capillary pressure. Cellulose paper substrate has exhibited great potential on microfluidic devices owing to prevalent obtainability, easy fluid (sample) flow system, flexibility, and low cost. Cellulose paper is fibrous, biocompatible, and hydrophilic in nature due to the hydroxyl group of the cellulose molecule. Based on the dominance of functional hydroxyl groups, cellulose is very reactive and every single cellulose fiber acts like a microchannel on the paper substrates. Aggregation of inter- and intra-cellulose fiber chains has a strong binding affinity to it and toward materials containing hydroxyls groups. In this paper, impact of inter- and intra-cellulose fiber on the paper substrate has been discussed through an experimental study. For the addition of work a "hydrophobic penetration-on-paper substrate (Hyp-POP)" method has been shown by using TiO2 ink as a hydrophobic material to design the microfluidic channel on the Whatman cellulose filter paper (grade 1) as a paper substrate. In this experimental study, the intra-cellulose fibers of paper substrate interact through hydrogen bonds with water molecules and form a hydrophilic surface on paper substrate while TiO2 binds with intra-cellulose fibers by electrostatic forces which change the crystallinity of intra-cellulose fiber and make the surface of paper substrate; hydrophobic. Field Emission Scanning Electron Microscope (FESEM) analysis is conceded for microfluidic channel analysis on the paper surface and EDS is carried out for TiO2 ink contents analysis. It has been experimentally observed that the printing material of TiO2 ink with 17.2% Ti content is suitable to integrate hydrophobic barrier on paper substrate for microfluidic channel fabrication. The wetting ability of Whatman cellulose filter paper (grade 1) was further evaluated by contact angle measurements (Data physics OCA 15EC). Using "Hyp-POP" method a hydrophobic pattern (width 3140 μ m) on paper substrate has been made for the flow of liquid (blue fountain ink) into a paper fluidic channel (width 1860 μ m) without any leakage. [ABSTRACT FROM AUTHOR]

The paper focuses on the cutting behavior of Glass Fiber Reinforced Polymer (GFRP) composites and GNP–GFRP composites that contain varying amounts of Graphene Nano Platelets (GNP). GFRP composites are increasingly being used in a variety of industrial applications due to their excellent mechanical properties, such as high strength, stiffness, and low weight. However, their machining and cutting behavior can be challenging due to the presence of the reinforcing fibers. Therefore, the study aims to investigate the machining behavior of GFRP composites and the effect of adding GNP on their cutting behavior. The effect of different parameters such as cutting speed, feed rate and reinforcement rate on cutting forces and delamination factor is investigated. In addition, the tensile strength and fatigue behavior of the composite materials with the best and worst delamination factors were also determined. Addition of up to 0.2 wt.% of GNP to GFRP composites resulted in an increase in cutting forces and delamination factor when drilling GFRP composites. While the cutting force and delamination factor decreased with the increase in cutting speed, the cutting force and delamination factor increased with the increase in the feed rate. Analysis of variance (ANOVA) was performed to determine the effects of drilling parameters and reinforcement ratio on cutting force and delamination factor according to full factorial experimental design. The most efficient factor on the cutting forces is found to be feed rate (84.97%), followed by the reinforced rate (6.48%) and cutting speed (6.13%). The most efficient factor on the delamination factor is determined to be feed rate for (44.49%), followed by the reinforced rate (29.20%) and cutting speed (21.73%). [ABSTRACT FROM AUTHOR]

The micromixer is an important prerequisite for realizing the function of the microfluidic chip system. Micromixers are mainly used in protein crystallization, biological reactions, drug delivery and other fields. Efficient micromixers enable fast bioreaction processes. In this paper, according to the principle of plane geometry, micromixers with three different structural obstacles, circular, equilateral triangle and square, are designed to study how to improve the mixing efficiency of the micromixer. In this paper, the influence of the obstacle structure on the mixing efficiency and pressure drop of the micromixer is analyzed. Through numerical simulation, the results show that when Re = 100, the mixing efficiency of the circular obstacle micromixer is up to 97.4%, and the pressure drop is 15,789.597 Pa. In addition, this paper analyzes that the use of cylindrical obstacles can make the fluid generate horizontal and vertical vortex flow, break the usual laminar flow, and significantly improve the mixing efficiency. [ABSTRACT FROM AUTHOR]

This paper reviews the application of atomic force microscopy (AFM) in analyzing the nanoscale morphological properties of key carbon nanomaterials: carbon nanotubes (CNTs), graphene, and fullerene. AFM imaging techniques, operating at sub-nanometer resolutions of approximately 0.5 nm, are utilized to evaluate surface topography, roughness, and dimensional attributes. CNTs exhibit diameters ranging from 1nm to 10nm, with surface roughness correlating to their mechanical strength, reported to exceed 50GPa. For graphene, AFM measurements confirm a monolayer thickness of ∼0.34nm, while defects such as wrinkles and grain boundaries are identified, which significantly influence its exceptional thermal conductivity of up to 5000 W/mK. Fullerene structures, characterized by their spherical morphology and uniform diameters averaging 0.7nm, demonstrate superior dispersion in composite matrices. The review further explores the synergistic effects and trade-offs in utilizing these nanomaterials as fillers in composite systems. For instance, graphene improves electrical conductivity by over 200% in polymer composites, while CNTs contribute significantly to mechanical reinforcement, and fullerene enhances chemical stability and compatibility in biomedical applications. Through comparative analysis, the paper identifies pathways to optimize filler performance through tailored dispersion and functionalization. These insights serve as a foundation for future innovations in nanomaterial-enhanced composites across industries. [ABSTRACT FROM AUTHOR]

This paper presents the development of an innovative numerical decision-making model aimed at identifying the optimal combination of process parameters during friction stir welding (FSW) of dissimilar AZ31B magnesium (Mg) and AA6082 aluminum (Al) alloy plates. The study considered not only the tool’s traverse speed and rotational speed as input parameters but also the positioning of the AZ31B Mg alloy on either the advancing side (AS) or the retreating side (RS). A total of 21 experimental runs were conducted, with tensile strength, elongation percentage, impact energy, and hardness evaluated as performance outcomes. In the first phase, a multi-criterion decision-making (MCDM) methodology was employed to develop the numerical model and identify the ideal set of parameters. To ensure the model’s reliability and accuracy, a sensitivity analysis was conducted. The results obtained from the MCDM model were validated by comparing them with those derived from a fuzzy logic-based decision-making approach. In the second phase, a response surface methodology (RSM) was applied to construct a numerical model using multivariate regression. A trade-off analysis, utilizing a multi-objective RSM approach, was performed to optimize the parameter combination. The optimal solution, computed through this approach, was further validated via a confirmation experiment. The ideal combination of process parameters — rotational speed of 841.42rpm, traverse speed of 0.5mm/s, and positioning of AZ31B Mg alloy on the advancing side — yielded a tensile strength of 214.65MPa, elongation of 10.76%, hardness of 74.89HV, and an impact energy of 6.01J. This research paper demonstrates the effectiveness of the proposed hybrid MCDM-RSM model in accurately determining the optimal FSW parameters and highlights its potential application in similar joining processes. [ABSTRACT FROM AUTHOR]

During the braking process, frictional heat generation between brake strip and brake block can lead to high temperatures, significantly affecting the braking performance. This paper proposes a novel knee impact test method and innovatively investigates the effect of brake friction surface texture shape on braking performance. A comparative evaluation of the braking performance of different surface textures is conducted using the new knee impact test, with a focus on studying the temperature rise during braking to optimize the brake system. Research findings indicate that the best braking performance was achieved when friction surface texture of the brake block was rhombus-shaped with a diagonal ratio of 5:5. By implementing this improved brake design, the maximum temperature during braking was reduced from 184.44∘C to 75.963∘C, resulting in a significant reduction in thermal stress from 155.22 MPa to 64.40 MPa. Moreover, the acceleration and brake distance are extracted and compared with the target values of Euro NCAP. The improved brake acceleration exhibits stability and a deviation from target value within 10%. Additionally, the deviation between our brake distance and target distance is −3.63%. These results provide a valuable reference for improving the braking performance of braking systems in the new knee impact test. [ABSTRACT FROM AUTHOR]

As China continues to advance the modernization process, a large number of infrastructure construction projects need to use shield machines to build tunnels. As a key component of the shield machine/TBM direct contact working environment, the hob is extremely complex and extremely harsh due to the extremely complex and extremely harsh working environment, resulting in hobs. It is very easy to damage when in service. The damage of the hob directly leads to many problems such as project delay and capital consumption. Therefore, improving the mechanical properties of the hob and prolonging the service life is an important engineering problem to be solved urgently. Based on the service performance of disc cutter, this paper analyzes its failure form and wear mechanism, and summarizes the strengthening process and improvement method of the H13 steel disc cutter ring. In this paper, the advantages and disadvantages of previous researchers and optimization methods are reviewed for H13 steel material composition, heat treatment process, surface coating strengthening process, and other processes. Finally, the performance strengthening of hob cutter ring is discussed and prospected, in order to provide a reference for hob strengthening technology path and industrialization realization. [ABSTRACT FROM AUTHOR]

Hydrogen has received widespread attention as a new clean energy in order to reduce the carbon emissions of fuel vehicles. This paper studies a tubular microreactor based on methanol steam reforming. Methanol and steam are mixed in proportion and the chemical reaction takes place in a porous catalytic bed. For heating purposes, hot gas from the burner penetrates the reactor bed through heating tubes. Energy is supplied through the heating tubes to drive the endothermic reaction system. The microreactor is enclosed in an insulated jacket. In this paper, parameters such as methanol conversion and hydrogen concentration are evaluated by considering microreactor materials, heating gas temperature and flow direction, heating tube distribution, pressure drop and reaction channel length. First of all, choosing a microreactor material with a smaller thermal conductivity can avoid excessive heat loss, and improve heat transfer performance. Increasing the heating gas temperature leads to an increase in the temperature of the reaction zone, thereby increasing the CH3OH conversion rate and H2 mass fraction. Changing the flow direction of the heating gas affects the reaction rate, but has little effect on the reaction result. Through the research on the distribution of the heating tubes, the results show that the hydrogen production rate is higher when the contact area between the heating tubes and the reaction zone is larger. Secondly, through the comparison of the data under different pressure drops, the best parameter P = 5 0 pa is obtained, and the CH3OH conversion rate is 80.6% at this time. Finally, increasing the length of the reaction channel can make the reaction more complete. For example, when the reaction channel length L = 0. 3 9 m, the CH3OH conversion rate is as high as 83.7%. [ABSTRACT FROM AUTHOR]

An experimental study on the tribology behavior and mechanism of NBR-Steel pair has been carried out. Abrasive paper was used to polish the NBR surface. The influences of surface topography on the friction coefficient were investigated based on the block-on-ring tribometer. Results show that polishing with abrasive paper is an effective method to reduce the friction coefficient of NBR on steel. Superlubricity was also found in the test. A new method to explain the superlubricity based on the contact angle and surface molecular structure was put forward in this work. Abrasive paper polishing changes the surface asperities, so affects the contact angle, so as to influence the boundary limiting shearing strength, and then causes the superlubricity. During the friction process the microstructure obviously changed, along with mechanical breaking of the molecular chain. [ABSTRACT FROM AUTHOR]

This paper highlights the surface roughness optimization of a specific material, Al 3003, which has been subjected to the non-equal channel angular pressing (NECAP) process. Considering spindle speed, feed rate, and depth of cut as input variables and surface roughness as an output variable, experiments have been conducted based on the L27 orthogonal array of the Taguchi method. Four prediction models, namely exponential and response surface methodology (RSM) as mathematical models, and artificial neural networks (ANNs) prediction models with different training algorithms (Bayesian Regularization (BR) and Levenberg–Marquardt (LM)), are proposed. Applying effectiveness and performance criteria, the prediction accuracy of the exponential model (90.35%), RSM (93.07%), BR (97.83%), and LM (97.54%) shows that all proposed prediction models are efficient enough. The ANN model trained with BR is found to be the best fit for predicting surface roughness. In order to optimize surface roughness, a newly introduced optimization method called the Intelligible-in-time Logics Algorithm (ILA) is employed. High spindle speed (1000rev/min), low feed rate (100mm/min) and depth of cut (0.5mm) have been the optimum cutting parameter combinations to obtain minimum surface roughness (0.4956μm). The results have been verified by confirmation tests and Particle Swarm Optimization (PSO) method. ILA and PSO predict the same optimum parameter combinations and minimum surface roughness, while ILA performs optimization in less time (114.4s), about 3.5 times faster than PSO. The paper’s findings strongly advocate the application of ILA in machining data optimization. [ABSTRACT FROM AUTHOR]

With the advent of the semiconductor age and later the age of nanotechnology, the thin film and coating field have established their importance and reasons for doing in-depth studies. Different sophisticated physical techniques, like chemical vapor deposition, sputtering, evaporation, molecular beam epitaxy, etc., and the conventional spin coating or dip coating, have been employed to get thin films of specific materials/compounds. Of all these, physical techniques are particularly preferred for their ability to develop good quality thin film with high uniformity. In the field of experimental material science, there are tremendous efforts in thin film development and the study of their different properties. The properties include topological, electrical, electronic, optical, or other. At the same time, though less explored, there are developments of theoretical understanding regarding the basic mechanism of thin film growth by specific growth mechanism. In doing this, the basic mechanism of thin film growth has been categorized into different broad classes with specific features. The main features include the time dependence of interface width and values of different scaling exponents. Apart from these, studies also addressed different morphological, optical, or electrical properties of the as-grown thin films of specific material. This paper gathers the existing literature that reports the simulation-based theoretical studies related to thin film growth by different algorithms like random deposition, ballistic deposition, random deposition with surface relaxation, or their different combinations. Not only that, but the paper also summarizes different reports related to the simulation-based prediction of the material properties. As the topic is relatively new, the collection of reports added in the last 20 years has been considered.The paper has different sections. Section 1 gives basic introductory ideas related to thin film development and its properties. Sections 2 and 3, respectively, deal with the basics of different existing models and the basic steps involved in the simulation. Section 4 gathers the related results reported by various researchers, followed by a short discussion and final concluding remarks. Undoubtedly, this paper is the first review work in this field and thus will serve as an invaluable source of information for future workers. [ABSTRACT FROM AUTHOR]

Digital technologies sustain today's world. Every part of the world is working towards digital technologies, which none of us can eliminate. Enormous growth is achieved only by unexpected acceleration by digital technologies, including the Internet of Everything (IoE), Artificial Neural Networks (ANN), Machine Learning (ML), Internet of Things (IoT), Artificial Intelligence (AI), Deep Learning (DL), and many more. These technologies started occupying all the engineering sectors, including manufacturing. This paper focuses on tribology analysis related to manufacturing concerning various digital manufacturing technologies. The paper narration includes Tribology using digital technologies wherein the journals and patent landscape analysis abet them. In trend, Tribology utilizes all these technologies today and envisages its growth with the predominant technological invention in the border view. The survey of various literature reveals that only three digital technologies, including AI, ML, and ANN, are used by tribologists around the globe. Other Technologies like Evolutionary Algorithm (EA), Support Vector Machine (SVM), and Adaptive Neuro-Fuzzy Interference Systems (ANFIS) are not used predominantly. [ABSTRACT FROM AUTHOR]

With the rapid development of intelligent materials in recent years, intelligent hydrophobic materials have become a new research direction, and hydrophobic surfaces with adjustable wettability have enormous application potential in many fields. Generally speaking, surface wettability is determined by the combined effect of surface chemical composition and surface morphology. Therefore, the photoresponsive wettability of azobenzene-modified surfaces can be achieved by constructing rough surface of micro-nano scale and reducing the surface free energy. In this paper, we synthesized two photo responsive hydrophobic azobenzene derivatives (AAAB-PFDT and UAAB-PFDT), characterized their structure, thermal degradation behavior, and microscopic morphology. The light conversion performance of the two materials in dispersion was also studied using a UV–Vis spectrometer. By depositing the materials on the glass slide, the measurements of the water contact angle (WCA) under different lighting conditions were performed, demonstrating that both materials exhibit excellent photoswitchable hydrophobicity and reversibility. [ABSTRACT FROM AUTHOR]

The surfaces of engineering components experience severe conditions during service life and may lead to catastrophic failure if proper care is not taken. The coating is one of the best possible ways to enhance surface properties of a part. Tungsten inert gas (TIG) cladding has emerged as a new technique which shows promising results in surface cladding domain. This paper deals with the recent developments in TIG cladding process. The processing parameters associated with the TIG cladding process are discussed. The microstructure, microhardness, wear, and corrosion behavior of the TIG-cladded layers are mentioned and correlated with the processing conditions. Finally, this paper concludes with some suggestions for future research. [ABSTRACT FROM AUTHOR]

Ni-based superalloys fall under the category of difficulty in machining type material owing to their poor thermal conductivity and high strength at extreme temperatures. Machining such materials using the traditional approach is a tremendously difficult task. On the other hand, EDM, one of the most sophisticated electro-thermal manufacturing processes, is used to machine such materials. It is a well-known non-traditional machining process for generating parts that require accuracy, have complex shapes, and are small in size. However, the use of EDM in Ni-based superalloys has some disadvantages like poor surface finish and low material removal rate. So, to alleviate these disadvantages, researchers introduced powder mixed dielectric fluid in the EDM process. Further, the performance of this technique has been enhanced by studying the effect of various nano/micro-size particles and their concentrations in the dielectric medium. In this paper, the authors have reviewed the impact of non-electrical and electrical process parameters on the output responses when machining Ni-based superalloys using powder mixed EDM. The challenges faced during the conventional machining of Ni-based superalloys and the mechanism proposed for powder mixed EDM, especially under the influence of suspended powders into the dielectric medium have also been presented in this paper. Finally, future research areas of powder mixed EDM of Ni-based Superalloys, such as (i) its modelling and simulation and (ii) the effect of tool motion and powder properties on its performance, are discussed in brief. [ABSTRACT FROM AUTHOR]

Inconel alloy has been a solution to diverse fields where automobile industry, aircraft, nuclear reactor are the foremost and major applicants of Inconel alloy. But the aim is precise manufacturing in minimum time. Inconel is known for its hard to machine characteristic. This paper illustrates the machining effect on Inconel 601 in EDM. Electrode discharge machining with its ability to machine hard conductive metals is the most recognized and suitable nonconventional machine for the purpose. Experiments with four level of variation and five parameters, (that is, OCV, peak current, pulse on time, duty factor and flushing pressure) have been conducted in 16 different combinations under L16 orthogonal array. Metal removal rate (MRR), surface roughness ( R a ), surface crack density (SCD), and white layer thickness (WLT) have been calculated herein. Surface roughness has been depicted with the help of Taylor Hobson materialize finishing tester. The view of the fact that conventional Taguchi technique cannot be used to solve the multiple response optimization problem independently, so TOPSIS method has been used in this paper to convert multiple responses into an aggregated performance index (called closeness coefficient C i + ) which has been optimized finally by the Taguchi technique. In this, MRR and Ra have been optimized by using the TOPSIS technique and it is found that by using optimal setting i.e. A4B1C2D1E 2 , MRR will be higher while Ra will be lower. Moreover, micro-graphical studies have been conducted to analyze various surface irregularities (SCD and WLT) of EDMed Inconel 601. SCD and WLT have been investigated with respect to optimal settings (A4B1C2D1E2) and obituary settings run no. 10 (A3B2C4D3E1) and better results have been obtained in optimal settings as compared to obituary settings. [ABSTRACT FROM AUTHOR]

In this paper, the machinability aspects of Ti-5553 have been experimentally investigated during Electro-Discharge Machining using three different geometrical shapes of copper electrodes i.e. cylindrical, triangular, and square. TIMETAL (Ti-5553) is a titanium-based alloy extensively used for special aerospace and marine applications due to its high strength and higher hardenability. By changing each of the aforementioned process parameters at three distinct levels, experiments based on the L 2 7 orthogonal array (OA) design of the experiment (DOE) were carried out. The machining performance has been carried out by utilizing different input parameters i.e. current, pulse off time ( T off ), flushing pressure ( F p ), tool shape ( T s ), and voltage (V) to examine machining performance characteristics like material removal rate (MRR), tool wear rate (TWR), surface roughness (Ra), white layer thickness (WLT), and surface crack density (SCD). Surface integrity in contents of surface morphology and surface topography is discussed herein. In this MRR, TWR, and Ra have been optimized by using a methodology (combining Grey relational analysis method and Taguchi's philosophy) and found the optimal parameters that will have more MRR and less TWR, Ra. Later SCD and WLT were investigated by employing the optimal setting (A3, B2, C2, D2, E1, F3) and arbitrary setting (A3, B2, C1, D3, E3, F2) and concluded that SCD and WLT are less by utilizing optimal settings for machining as compared to arbitrary settings. Among all three different geometrical shapes of copper electrodes, the cylindrical tool has been found to be the best suitable tool for machine Ti-5553. [ABSTRACT FROM AUTHOR]

Due to the unique properties of titanium (Ti) and its alloys, it has a particularly wide range of applications in aerospace, automotive, medical and other fields. However, the problems of low surface hardness, high friction coefficient and low wear resistance of Ti alloys limit its development to a certain extent. The destruction of Ti and its alloys often occurs on the surface of materials such as wear damage, corrosion, and oxidation resistance. Therefore, the exploration and application of surface strengthening technology is particularly important. The cathodic plasma electrolytic deposition (CPED) technology, as a surface modification technology, can achieve better adhesion and facilitate the material to achieve better comprehensive performance. This paper briefly introduces the basic concepts, principles and development progress of CPED. Starting from the preparation of ceramic coatings, metal coatings, diamond-like carbon films and composite coatings, it summarizes the application of CPED in Ti and its alloys. Applications in alloys to improve thermal oxidation resistance, wear resistance, corrosion resistance, and film-based adhesion. At the end, its development in the new era environment is prospected. [ABSTRACT FROM AUTHOR]

Nanoparticles have the capability to augment the thermal conductivity of nanofluids. For the transmission of heat, the material's low thermal conductivity is the key problem. Therefore, to increase the thermal conductivity, researchers mixed different nanoparticles in the base fluids. In this field of study, utilizing three different particles is the most recent strategy to form a ternary hybrid nanofluid that gives us better results in terms of heat transfer. The interaction of three different kinds of nanoparticles, i.e. copper, alumina and silver, is considered with water serving as the base fluid to form a ternary hybrid nanofluid. The paper explores the behavior of ternary hybrid nanofluids on heat and mass transportation phenomena of the two-dimensional magnetohydrodynamic (MHD) micropolar flow across a porous extending surface with zero mass flux and convective conditions. The Brownian motion, thermal radiation, heat source and sink, and joule heating are taken into consideration in the temperature equation. The chemical reaction is incorporated into the concentration equation. Appropriate similarity transformations are used to transform the system of partial differential equations (PDEs) to a coupled system of ordinary differential equations (ODEs). The homotopy analysis method (HAM) is used to solve the system of the flow equations. The effects of the nanoparticle's volume fractions and other different physical parameters on the surface drag force, Nusselt number, velocities, microrotation, temperature and concentration profiles are scrutinized through figures and tables. The outcomes of the present investigation show that the heat transfer rate is augmented with the increasing value of thermophoresis parameter. The magnetic field has augmented temperature while the opposite result is seen in velocity and microrotation profiles. With the escalating values of thermophoresis parameter, the concentration and temperature of ternary hybrid nanofluids are boosted while the increasing Brownian and chemical reaction parameters have decreased the concentration profile. The surface friction coefficient exhibited by the ternary hybrid nanofluid is higher than hybrid and conventional nanofluids. [ABSTRACT FROM AUTHOR]

Due to their superior corrosion resistance at high temperatures, stainless steels have a wide range of applications in numerous industries (including chemistry, the petrochemical industry, the paper industry, and nuclear engineering), it is also utilized in the medical industry as an implant material. To enhance the outstanding qualities of stainless steel such as high temperature corrosion, surface coating methods are also used. Boronizing, nitriding, thermal spray coating, physical vapor deposition, chemical vapor deposition, and electro-spark deposition procedures are used to apply these coating processes to steel surfaces. The electro-spark deposition (ESD) coating technology is one of the most promising approaches in this area. Using high-frequency and high-current electric pulses, the ESD micro-welding procedure bonds electrode material to the surface of a metallic substrate. In this study, AISI 304 and AISI 316L stainless steels were coated with FeAl and NiAl intermetallics using the ESD method. First, suitable experimental parameters for ESD coating were established. Second, X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to characterize the microstructures and phases that formed on the coated surfaces. Then, the surface hardness of the resulting layers was determined. Finally, the corrosion properties of intermetallic-coated stainless steels were determined using electrochemical methods and compared with each other. As a result, both the hardness values and corrosion resistances of both stainless steel sheets have increased with intermetallic coatings. [ABSTRACT FROM AUTHOR]

The bacterial spread can pose a significant risk in the transmission of infectious diseases. Nanomaterials, including synthetic antibacterial nanoparticles, have emerged as a promising solution to combat bacterial infections due to their unique physicochemical properties. Metal nanoparticles have been shown to exhibit potent antimicrobial activity against a broad spectrum of bacteria, including both gram-positive and gram-negative strains. One of the main advantages of using metal nanoparticles as antibacterial agents is their ability to penetrate the bacterial cell wall and disrupt cellular processes. This disruption can lead to the inhibition of bacterial growth and ultimately, bacterial death. Furthermore, metal nanoparticles can be engineered with specific surface modifications that enhance their antibacterial activity and improve their biocompatibility. These modifications can include the attachment of targeting ligands, peptides, or antibodies to the nanoparticle surface, which can increase their specificity toward bacterial cells and reduce their toxicity toward mammalian cells. Overall, the use of metal nanoparticles as antibacterial agents holds great promise for the development of novel therapeutic strategies to combat bacterial infections, both in vitro and in vivo. In this paper, we highlight the development of metal NPs, particularly those based on Mn, Fe, Co, Zn and Cu for their antimicrobial properties and related mechanisms. [ABSTRACT FROM AUTHOR]

The α -Fe(100)/Cr(100) interface has an important effect on the precipitation of the Cr-rich phase in ferritic stainless steel, and alloying elements affect the stability of the α -Fe(100)/Cr(100) interface. However, it is difficult to clearly understand the effect of alloying elements on the α -Fe(100)/Cr(100) interface behavior experimentally. Therefore, the first-principles calculation is employed to address this problem in this paper. First of all, the segregation behaviors of alloy elements (Mo, Nb, and Si) on the α -Fe(100)/Cr(100) interface were systematically investigated. And then, the effects of these alloying elements on the property of the α -Fe(100)/Cr(100) interface were studied. Based on the density functional theory, the work of adhesion (Wad), interfacial energy (γint), doping energy (E f ), and electronic properties of the α -Fe(100)/Cr(100) interface were analyzed. The results show that the body-centered α -Fe(100)/Cr(100) interface is constructed by using seven layers of α -Fe(100) and Cr(100) surface models. The Wad is 6.115 J.m − 2 , and the γint is −0.12 J.m − 2 . The doping atoms tend to segregate on the surface of α -Fe(100). When the Si atom doped in the interface, the Wad increases, and the γint reduces. The doping of the Si strengthens the bonding strength of the interface and promotes the nucleation of the Cr-rich phase. While the addition of Mo and Nb atoms decreases the Wad of α -Fe(100)/Cr(100) interface, increases the γint. The bonding strength of the interface is weakened and the nucleation of the Cr phase is inhibited. Based on this result, it is clearer to understand the effect of Mo, Nb, and Si atoms on the precipitation of the Cr-rich phase in ferritic stainless steel. [ABSTRACT FROM AUTHOR]

Wire cut electric discharge machining (WCEDM) is a flexible and more essential for the precise machining of hard materials like composites and super alloys. In order to improve the surface texture as the main focus of the WCEDM process, the expansion of the fundamental procedural perceptive is very important. This paper mainly focuses on the prediction of surface quality of Al-Fe-Si alloy (AA8011) matrix composites during the WCEDM process. For the fabrication of composites, the varying proportions (0, 5, 10 and 15 wt.%) of ZrO2 ceramic particle were incorporated with AA8011 matrix alloy by using stir casting method. In the machining studies, to investigate the effects of reinforcement (wt. %) and the WCEDM process parameters, namely pulse current (amps), pulse-on time (μ s) and pulse-off time (μ s) on machining performance like surface roughness (SR) of the proposed composites. Based on the selection of parameters and their levels, an L16 (44) orthogonal array was most suitable for conducting the WCEDM experiments. A Taguchi technique was employed in this study to determine the optimal conditions of machining parameters through the signal-to-noise (S/N) ratio analysis. The result shows that the minimum SR is achieved at 5 wt.% of reinforcement, 6 amps of pulse current, 110 μ s of pulse-on time and 50 μ s of pulse-off time, respectively. Analysis of variance (ANOVA) results revealed that the reinforcement wt.% has the primary significant factor on SR, trailed by pulse-on time and pulse current, respectively. Furthermore, the regression equation was also developed to predict the SR and that values well agree with the experimental SR. [ABSTRACT FROM AUTHOR]

In this paper, a high-throughput droplet method is presented for screening corrosion inhibitors, particularly for those metals that are subjected to pitting. To this objective, AA5083 was used as a case study as it is subject to pitting corrosion in saline solution containing different corrosion inhibitors. This paper outlines how critical parameters are measured and calculated (average pit depth and maximum pit depth) and the errors and consistency of the method, and the definition of corrosion inhibition via the method. The results from this method were then compared to the results of inhibition efficiency derived from potentiodynamic polarization scans for inhibitors with a range of performance. The method was conducted at temperature T = 2 2 ± 2 ∘ C inside a humidity chamber, and concentration 10 − 3 M of seven chemical compounds that have similarities in their structures. The discrepancies were profound for the cases where the inhibitor was of low efficiency, which is ascribed to the fact that these pits' growth is dominated by that of a few large pits. [ABSTRACT FROM AUTHOR]

Electrical discharge machining (EDM) is widely applied for machining difficult-to-cut materials in mold and die industries. However, the major limitations associated with the EDM are low productivity and poor surface integrity of the machined surfaces. In recent years, several developments have been applied to overcome such limitations of EDM. Electrical discharge grinding (EDG) is a hybrid machining process that simultaneously involves the spark erosion action of EDM and the mechanical abrasion action of the grinding wheel for the material removal purpose. The rotating motion of the grinding wheel also contributes to the easy removal of debris particles, thereby improving the material removal. It is evident from the literature that the rotating motion of the grinding wheel enhances the flushing mechanism resulting in better performance of the process. This paper aims to present a comprehensive review of the research carried out in EDG, highlighting the result of the experimental, modeling, and optimization techniques applied in this area. Initially, the background of EDM and the need for hybrid EDM processes have been presented. Then, a few hybrid EDM processes have been discussed, addressing their advantages and limitations. Further, the concept of EDG and electrical discharge diamond grinding (EDDG) has been discussed, along with the classification of the EDDG process. Finally, this paper explores the current research status and future research perspective in the area of EDG and EDDG processes. [ABSTRACT FROM AUTHOR]

Super-hydrophobicity inspired by natural water-repellent surfaces has received tremendous attention for surface functionalization of metallic materials in many applications. Problems of corrosion and/or contamination that happens on the surface can be partially solved as the material obtained super-hydrophobicity. Appropriate surface pattern and low surface energy are the two key factors that can realize super-hydrophobicity. In the present paper, laser surface texturing (LST) followed by decoration of Hexadecyltrimethoxysilane (HDTMS) was conducted to manipulate the super-hydrophobicity and corrosion resistance of AISI 316 stainless steel (SS) on the surface. Scanning electron microscopy (SEM) and an ultra-depth field microscope were employed to characterize the surface morphologies of the received samples before and after corrosion tests. Corrosion resistance and super-hydrophobicity for the related samples were investigated using electrochemical tests and water contact angle measurements. It was found that various surface patterns differed with intervals (250, 150, 80, and d=50μm,) between two micro-dimples have formed on 316 SS sample surfaces after LST treatment. The surface roughness values gradually increased with the decrease of interval. The 316 SS samples obviously reduced surface energy values after HDTMS decoration. In simulated haze solution, electrochemical tests demonstrated that the 316 SS sample treated with HDTMS+LST (HT-316 SS, d=50μm) exhibited lower corrosion and higher corrosion potential current density than the smooth 316 SS (S-316 SS), HDTMS+S-316 SS (HS-316 SS), and LST 316 SS (T-316 SS, d=50μm) samples. As expected, the HT-316 SS (d=50μm) exhibited the highest water contact angle of 155.85∘ as compared to HS-316 SS and other HT-316 SS samples. Meanwhile, the superhydrophobic surface of HT-316 SS (d=50μm) exhibits super-oleophilic and self-cleaning properties. [ABSTRACT FROM AUTHOR]

In this paper, an experimental investigation of the machinability of Titanium grade 23 has been carried out using hybrid micro-textures on the cutting tool. The different types of micro-textures have been fabricated on the rake surface as well as on the flank surface of the cutting tool. The performance of textured tools with the presence of a chip breaker has been investigated. The selected patterns were vertical grooved rake face (VT-R), diagonal grooved rake face (DT-R), vertical grooved flank face (VT-F) and hybrid textured tools namely, vertical rake and flank (V+V), diagonal rake and vertical flank (D+V). A comparative study has been carried out to acknowledge the performance of textured tools while dry turning Titanium Grade 23 alloy. The machinability has been made to acknowledge the performance of textured tools with the variation of machining time in case of dry turning operation. The machinability criteria are investigated based on cutting forces, cutting temperature and tool wear mechanisms involved while machining. The performance of the cutting tool with DT-R and VT-F micro-texture is observed to be better in comparison to others. Innovative applications of micro-textured tools are for dry green machining without any environmental hazards and proper chip-flow control. [ABSTRACT FROM AUTHOR]

Friction stir processing (FSP) is used for changing the microstructure and material properties improvement. In modern years, special attention is exposed by governing the temperature level, and is applied by various coolants spraying on the top surface of the sample during FSP. This review paper explores the impact of several cooling mediums such as normal water, cold water, hot water, and cryogenic on the temperature distribution, grain refinement, mechanical characteristics, and superplastic deformation behavior of FSP using various grades of magnesium (Mg) alloys. It also includes the corrosion rate and wear behavior of FSP on Mg alloys. Through the systematic review, it has been observed that refined grains were formed and the generation of intermetallic compounds was suppressed after FSP in underwater and cryogenic conditions, leading to a notable increase in strength. The higher tensile strength and elongation are exhibited while using cryogenic compared to water medium. This is due to a rapid cooling process, where the high temperature was short for the newly-formed grains to fully develop. This review not only concludes the key findings of the preceding research but also suggests future recommendations. [ABSTRACT FROM AUTHOR]

The stability test of multi-station precision machining fixtures can improve the safety of multi-station precision machining fixture. This paper puts forward a stability test method of multi-station precision machining fixtures based on the pressure pulsation amplitude test. The fundamental frequency characteristic detection of airflow pulsation is adopted to collect the stability characteristic parameters of multi-station precision machining machine clamps, and the wave number analysis model of airflow pulsation in the stable state of multi-station precision machining machine clamps is constructed. The time domain characteristic parameter analysis and spectrum gain control are adopted to realize the stability condition parameter analysis and spectrum characteristic decomposition of multi-station precision machining machine clamps. The end-face pulsation attenuation characteristic method of detection is followed to realize noise reduction of the stable air pulsation attenuation signal of multi-station precision machining fixture, and the rotor meshing frequency component of the stable air pulsation attenuation signal of multi-station precision machining fixture is extracted. The multi-scale wavelet air pulsation attenuation signal decomposition is adopted to realize the correlation spectrum characteristic detection of the signal, and the multi-dimensional space fusion is employed to realize signal characteristic clustering, thus realizing the stability detection of multi-station precision machining fixture. The test output shows that the proposed method has better convergence and strong feature clustering in the stability detection of multi-station precision machining machine fixtures, which improves the confidence level of multi-station precision machining machine fixture failure instability detection. [ABSTRACT FROM AUTHOR]

Due to the error between the strain measured by the fiber grating sensor pasted on the surface of the substrate and the real strain of the substrate, the analysis of the relationship between the strain measured by the fiber and the actual strain of the substrate is the focus of this research. Since structures are subjected to various harsh conditions in actual service, such as temperature changes, fatigue, corrosion, aging, cracks and other external factors, when using surface-adhesive fiber Bragg grating (FBG) sensors for structural health monitoring, all external factors may affect the measurement accuracy of the sensors and cause measurement errors, so it is necessary to consider some specific factors in a comprehensive manner. In this paper, we theoretically study the average strain transfer rate of the three-layer strain transfer model of a surface-adhesive fiber grating sensor under the effects of temperature change and fatigue load, derive the formula for the average dynamic strain transfer rate under the combined effects of two external factors using the shear-lag method and analyze the parameters of the fiber-optic sensor to correct the error and optimize the measurement accuracy of the sensor in order to better monitor the structure under temperature change and fatigue load. The shear hysteresis method is also used to analyze the parameters of the fiber-optic sensor to correct the errors and optimize the measurement accuracy of the sensor in order to better monitor the real dynamic strain of the substrate under temperature and fatigue loads and provide theoretical guidance for its measurement. [ABSTRACT FROM AUTHOR]

In the recent years, Additive Manufacturing (AM) has become a very demanding process utilized by majority of the manufacturing industries due to its complex geometrical capabilities, high accuracy, minimal material usage and better build quality. Among the various types of AM methods, Direct Metal Laser Sintering (DMLS) is a feasible method with many applications and a lot of scope for research. This paper focuses on optimizing the important parameters of DMLS process for better build quality of AlSi10Mg Aluminium alloy. The parameters identified are laser power, hatch distance, scanning speed, and layer thickness. Grey–Taguchi multi response optimization method has been used. Experimental specimens were fabricated and tested. Micro-Vickers hardness and average surface roughness were studied. Experiments were analyzed to determine the best combination of parameters of the DMLS process. A detailed micro-structural study was conducted on the specimens. Also, crystallographic study was made. The resultant specimen thus produced had a better build quality along with satisfying micro-structural characteristics. [ABSTRACT FROM AUTHOR]

Welding, despite being the most efficient joining process, has significant negative impact on the environment and worker health. This paper presents the environmental impact of various conventional welding processes and sustainability of Friction Stir Welding–a Green technology which requires no filler material, no shielding gas, no flux and involves no gas emissions. It is an energy-efficient process that saves significant amount of power and energy when compared to conventional welding processes. The defect-free welds produced have better mechanical and metallurgical properties than other processes. The higher temperature distributed due to the friction heat is established as the source of weld failure. Cooling the weld joint controls the heat conduction thus further enhancing the weld properties. This review paper explores the different cooling techniques employed for cooling the joint during Friction Stir Welding process. The changes in temperature distribution and microstructure caused by the cooling applied and the consequential transformation in material flow, tensile strength, hardness, corrosion, wear, residual stress are discussed. The changes in weld properties obtained by using different cooling media on different materials are reviewed. [ABSTRACT FROM AUTHOR]

In the ongoing few years, electricity cost is bound to increase so as a result, innovations in the photovoltaic industry are worth promising. One of the new ventures, kesterite (Cu2ZnSnS4) plays a significant role in fulfilling the energy demands due to its high earth abundance, non-toxicity, and low-cost processing characteristics. This semiconductor thin film can be considered as an alternative to CIGS where the expensive and scarce resources such as indium (In) and gallium (Ga) are replaced with cost-effective and abundant zinc (Zn) and tin (Sn). In this paper, the variations in the concentration of precursors of kesterite– copper, zinc, tin, and sulfur, and their influence on structural and optoelectrical characteristics of kesterite thin films have been reviewed and their effects are discussed. [ABSTRACT FROM AUTHOR]

Explosives can be divided into low and high, the efficient detection of which is of utmost importance for security reasons. A major component of high explosives is the nitroaromatic compounds. These explosives, when sealed, have difficulty detecting. In this review work, the major techniques for explosive detection i.e. animal olfaction, calorimetric sensors, immunosensors, ion mobility spectrometry, and Raman spectroscopy are discussed. The materials or compounds comprising nitroaromatic sensors have been a topic of major research for the last three decades. Nanomaterials do provide an acceptable solution for portable, affordable, and efficient detection of analytes of explosive nature due to their redox properties. 3D nanomaterials like TiO2, Au, SiO2, Ag and CdSe-ZnS, 0D materials like CdSe, CdTe, ZnS and MoS2 can detect nitroaromatic compounds efficiently. In the upcoming technology, the incorporation of quantum dots is also considered for explosive detection. As an option for prospective research in the field, development in the use of boron nitride for detecting explosives is also a good option. A comprehensive review of such materials is discussed in this review paper. [ABSTRACT FROM AUTHOR]

Currently, electrochemical anodizing is one of the most common processes in materials science, since, under the right conditions, it allows to modify the material surface without damaging it by means of redox reactions, generating an oxide layer that protects the material and improves its properties. In this paper, grade 2 titanium was anodized using a solution of hydrochloric acid, glycerol, and deionized water as electrolyte, and 0.5 M K2CrO4 as doping agent, with a voltage of 30 V for 4.5 h. After anodizing with and without chromium, annealing was performed at different temperatures (500 ∘ C, 600 ∘ C and 700 ∘ C) to promote structural and microhardness changes. The samples were analyzed by FE-SEM observing that the formation of nanostructures changes according to the heat treatment, where samples at 700 ∘ C with chromium begin to form nanorods and, compared to those without chromium, the nanorods are longer. The presence of Cr in anodized TiO2 at different temperatures was confirmed by EDS technique. Using XRD, the microstructure of TiO2 anodized with and without Cr was analyzed and anatase and rutile phases were found, with greater presence of anatase for samples with Cr. Finally, a maximum hardness of up to 10.27 GPa was obtained from the sample at 700 ∘ C without chromium, which is higher compared to the values of coatings with Cr. However, the anatase phase could be stabilized at higher temperatures making it suitable for medical applications since the anatase phase is the most biocompatible. [ABSTRACT FROM AUTHOR]

As implant materials, titanium and its alloys have been extensively utilized because of their exceptional mechanical properties and biocompatibility. Despite this, corporations and researchers alike have kept up their aggressive pursuit of better alloys since there are still issues that require immediate attention. One of these causes a problem with stress shielding as a noticeable variation in the elastic modulus of the implant material. Ti alloys release harmful ions after extended usage. The poor bioactivity of the Ti alloy surface slows the healing process. In order to address these problems, additional research has concentrated on developing Ti alloys for the 21st century that contain a more suitable phase and change the surface of the alloy from inherently bioinert to bioactive. This study assesses the knowledge presently existing on the biological, chemical, mechanical, and electrochemical characteristics of important β -Ti alloys created in recent years with the objective to provide scientific justification for using β -titanium-based alloys as a substitute for cpTi. Dental implants might be made using β -Ti alloys as an alternative. The enhanced alloy qualities, which include a lower modulus of elasticity, improved strength, suitable biocompatibility, and good abrasion and excellent resistance to corrosion, offer the essential proof. Additionally, structural, chemical, and thermomechanical modifications to β -Ti alloys allow for the production of materials that may be tailored to the needs of unique instances for clinical practises. By researching the paper, the performance and attributes of β -titanium alloy are compared to those of other forms of titanium alloy, such as α titanium alloys. To support their usage as cpTi substitutes, in vivo studies are required to assess new β -titanium alloys. [ABSTRACT FROM AUTHOR]

This paper discusses the various joining methods with faying surface modifications used to join AA6063 and AISI304L dissimilar alloys by Rotary Friction Welding (RFW) process at different welding conditions mainly with friction pressure (FP), upset pressure (UP) and friction time (FT). This paper also studies the tensile behavior of the welded joints. The fabricated dissimilar joints were tested using universal testing machine against tensile load, and the mechanical properties of all 30 nos. of weld joints like elongation (%), strength coefficient (K), strain hardening exponent (n), strain hardening rate (TS/YS ratio), shear strength, etc. were calculated from the tensile testing results and plotted here with a standard error bar. Hollomon's equation is considered here to study the stress and strain hardening relation and Von Mises yield criterion is considered for shear and yield stress correlation. Total elongation is also calculated from the initial and final length obtained during the tensile test. Since fracture ductility of the joints depends on the stress, strain, ' K ' and ' n ' values, it is important to study these mechanical properties and how the tensile results can be used for their estimation is detailed in this paper. The faying surfaces influence the mechanical properties as well. [ABSTRACT FROM AUTHOR]

Dissimilar welding of duplex stainless steel (DSS) with high-strength low alloy (HSLA) was more complicated since they were utilized in automotive and aerospace design, which needed components with lower weight, higher tensile strength (TS), hardness, corrosion resistance. In this research paper, the main objective was to establish a gas tungsten arc welding process, on a 60∘ angle double groove on both sides of DSS and HSLA, using three different filler metals ER2594, ER70S2 and ER304. The welded surfaces of the specimens were analyzed to assess the microstructural characterization using SEM and Edax, and they were also tested to determine their mechanical and corrosion characteristics. In comparison to microstructural characterization, Mn and Si combination decreased the surface defects in the weldment made by ER2594. The determination of mechanical properties revealed that specimen A produced by ER2594 was superior to other specimens B and C, in terms of yield stress, TS and hardness. Similarly, improved corrosion resistance was achieved by the larger presence of Cr along with Ni in ER2594. In the welded joint, Ni combined with an appropriate proportion of other alloying elements in ER2594 enabled effective control over the ferrite-austenite phase balance, which was crucial for achieving the necessary combination of properties and weldability designed for particular applications. Among the three filler metals, ER2594 showed better microstructure uniformity, enhanced TS, hardness and superior corrosion resistance. [ABSTRACT FROM AUTHOR]

Molten salts are extensively used as high-temperature heat transfer media and thermal energy storage (TES) materials in concentrating solar power (CSP) plants. Molten salt corrosion is a critical factor influencing the safe operation of the system. This work comparatively summarizes various factors influencing molten salt corrosion, including temperature, impurities, alloy composition and gas atmosphere. Additionally, the corrosion mechanisms of nitrate, carbonate, chloride, and fluoride-based mixture salts are meticulously reviewed. The demand for high-temperature storage is indeed increasing, driven by the need for more efficient and sustainable energy solutions. High-temperature storage systems, particularly those utilizing phase change materials (PCMs) and molten salts, play a key role in enhancing energy efficiency and reducing carbon footprint. By improving the efficiency of energy storage and reducing the need for fossil fuels, high-temperature storage systems help decrease greenhouse gas emissions, contributing to the fight against global warming. The paper focused on enhancing the corrosion resistance of container materials in terms of improving PCM thermal conductivity and stability. [ABSTRACT FROM AUTHOR]

This paper explains about the mechanical insertion of graphite particles into aluminum (Al-1100) surface for forming composites on the surface through an electrical resistance heat-supported pressing procedure. The surface of the aluminum is first graphite coated by solution casting. To achieve impregnation, the graphite–aluminum interface is locally heated with the assistance of electrical resistance heating followed by mechanical pushing. The degree to which aluminum surface softens can be regulated by process factors like current and heating time. Microstructural characterization of aluminum–graphite composite was carried out with SEM, TEM, Raman spectroscopy and XRD. It was revealed from the microstructural characterization that graphite particles were impregnated into the aluminum surface without agglomeration. Raman spectroscopy of graphite-impregnated surface shows a shift in major graphite peaks and an increased ratio of intensity ( I D / I G ). The presence of carbide compound (Al4C3) was not detected from the XRD and TEM studies. The mechanical property examination of the surface was carried out by nanoindentation and the subsurface was characterized by microhardness tests. It was observed that surface mechanical property and reduced Young's modulus were improved by more than 200% and 150%, respectively. The projected method can be utilized as a surface modification technique in solid-state by fabricating surface composites fabricated through mechanical insertion of particulate reinforcement at sub-melting temperatures of substrate and under an open producing environment. [ABSTRACT FROM AUTHOR]

The deposition of diamond films on tungsten carbide-based tools can greatly improve the life and performance of cutting tools. However, the deposition of diamond coatings on cemented carbide (WC-Co) suffers from poor film-base bond strength. In this paper, diamond coatings were deposited of phytocrystalline metal micropowders (pure, Nb, Ti, Ta) pretreatment method and the properties of diamond films were analyzed by energy spectrometry (EDS), scanning electron microscopy (SEM), Raman spectroscopy and bonding strength test of diamond films. The results show that through the experiment of the pretreatment process of surface implanted crystal metal micropowder, the best implanted crystal metal micropowder was obtained, the surface quality of implanted crystal titanium (Ti) coating was improved, the diamond Raman peaks were sharp and the indentation cracks had a crack diameter of 389 μm, which is small and has the highest bond strength. The pretreatment process of phytocrystalline diamond micropowder can deposit high-performance diamond coatings and improve the bonding strength between the coating and the substrate film base. [ABSTRACT FROM AUTHOR]

This paper outlines the TIG welding process without using active flux for 4 mm-thick plates of duplex stainless steel (DSS 2205) and austenitic stainless steel (SS 304L). It also provides the properties and behavior analysis of weldments. Complete penetration is achieved with multi-pass welding. The microstructure is examined using an optical microscope (OM) and a scanning electron microscope (SEM). It was used to report on the differences between the unpolished zone and the heat-affected zone (HAZ) in weldments. A Vickers hardness tester (HV scale 10) was used to assess the weldment's hardness. Tensile and bend failure were among the mechanical properties exhibited by the parent metals of DSS2205, SS304L, and dissimilar junctions. The findings demonstrated shallow gaps in the surface area and a greater ultimate tensile strength of 600 MPa for DSS similar welding. However, compared to other similar weldments, dissimilar weldments exhibit superior performance in bending conditions. [ABSTRACT FROM AUTHOR]

In this paper, experimental analysis was performed during micro-electrical discharge machining (micro-EDM) of titanium alloy Ti–6Al–4V (grade 5) using three types of tools viz. copper (Cu) tool, tungsten carbide (WC) tool, and synthetic graphite (Gr) grade three tool. The main process parameters were taken as (a) pulse on time ( T on ), (b) pulse off time ( T off ), (c) voltage (V), and (d) capacitance (C). The output responses were taken as the material removal rate (MRR) and tool wear rate (TWR). Taguchi method coupled with grey relational analysis (GRA) (L 1 6 orthogonal array) technique was applied to optimize the input process parameters for both the responses. Scanning electron microscopy (SEM) analysis of the workpiece and tool was also performed to investigate the morphology of the machined surface and tool surface. Energy-dispersive spectroscopy (EDS) analysis was performed to investigate the elemental composition of the machined surface. The experimental finding reveals that tungsten carbide is the most suitable tool material for machining the chosen workpiece for obtaining optimal MRR and TWR. The optimum condition for the copper tool was found as 180 V, 1000 pf, 10 μ s ( T on ), and 10 μ s ( T off ). Meanwhile, the optimum parametric condition for tungsten carbide and graphite tools was found to be the same as 240 V, 100 pf, 20 μ s ( T on ), and 5 μ s ( T off ). [ABSTRACT FROM AUTHOR]

This paper deals with the identification of optimized process parameters for FSW of 6mm thick CDA 101 Cu alloy plates. Three distinctive parameters, the tool’s traverse speed, rotational speed, axial load, have been considered as self-reliant variables for formulating a numerical model based on nonlinear regression-type approach, with the objective of anticipating mechanical attributes of joints. From the surface- and contour-type plots, it was revealed that the axial load in combination with rotational speed has played a dominant role in influencing the tensile and yield strength of the CDA101 Cu alloy joints. At the same time, the traverse speed of the tool has played a dominant role in enhancing the ductility of the CDA101 joints through the generation of ample volumes of frictional heat, which in turn have facilitated both coarsening of grain structures and softening of materials in an ideal manner. Employing tool rotational speed, traverse speed and axial load in the ranges of 1750–1900rpm, 23–27mm/min and 5.75–6.5kN, respectively, was found to enhance the tensile strength of the CDA101 Cu alloy joints. FSW process parameters attained through the numerical meta-model of RSM have led to the attainment of the highest value of tensile strength of 209.5MPa together with a 141.4MPa yield strength with very minimal fitting errors of 0.28% and 0.52%, respectively. A collection of additional experimental data has been employed to verify the formulated empirical-based formula and additionally, an entirely different optimization technique namely PSO (i.e. particle swarm optimization) was implemented for comparison and validation purposes. The formulated meta-model of RSM generated the largest value of % of elongation of 14.23%, though the relative percent error was around 1.988%, which was slightly larger than that of the value (i.e. 14.11%) generated by PSO, with a relative error of 0.58%. [ABSTRACT FROM AUTHOR]

Magnesium alloys have a huge market and broad prospects due to their high specific strength, good ductility, and strong thermal conductivity. However, the active chemical properties of elemental magnesium and the negative standard electrode potential result in magnesium alloys being highly susceptible to corrosion and failure. Chemical conversion treatment of magnesium alloy can improve its corrosion resistance by preparing a chemical conversion film on its surface. Rare earth conversion treatment has the advantages of effortless process, moderate price, no pollution, good corrosion resistance, and synergistic effect with inorganic or organic additives, which is in line with the pursuit of “green chemical” in industrial production. At present, there is little research and application on lanthanum-based rare earth conversion coatings (La-RECC). This paper selects rare earth element lanthanum (La) to prepare La-RECC on the surface of AZ91D magnesium alloy through chemical conversion treatment. The microstructure, chemical composition, and protective properties of La-RECC were discovered, as well as their interrelationships, revealing the degradation process of La-RECC in 3.5% NaCl solution. La-RECC is composed of La(OH)3 and Mg(OH)2, exhibiting a crystal cluster structure with cracks, and there are a large number of needle-like crystals on the crystal cluster of La-RECC, with a thickness of 2.14 μm. The degradation process of La-RECC can be divided into three stages: Rapid degradation, slow degradation, and complete degradation. The complete degradation time of La-RECC in 3.5% NaCl solution is 82.5h. [ABSTRACT FROM AUTHOR]

The paper provides an overview of the significance of nanomaterials as additives, in the tribological performance of lubricants. This review describes the ascendancy of different nanoparticles such as carbon-based nanoparticles, metallic nanoparticles, oxide nanoparticles, sulphide nanoparticles, nanocomposites, hybrid and bimetallic nanoparticles in lubricants. The study also evaluates the underlying principles of lubricant-nanoparticle interactions and their effects on wear prevention and friction reduction. The key parameters including particle morphology, particle size, weight concentration, and functionalization of the particle surface, that determine the friction and wear characteristics are discussed. Also, the science behind surface interaction and various mechanisms involved in friction and wear modification is described. The review highlights the prospect of various nanomaterials in the field of lubrication and facilitates development of advanced nanolubricants with superior tribological properties, that attributes to the reduction in energy consumption and improved performance. [ABSTRACT FROM AUTHOR]

In recent years, fiber-reinforced plastics (FRPs) materials like glass fiber-reinforced plastic (GFRP) and carbon fiber-reinforced plastic (CFRP) are next-generation polymer-based composite materials tailored for lightweight engineering applications in aerospace, marine, chemical, and automotive industries. Applying inclined holes in GFRP material is essentially used in producing robotic parts, microelectronics components, wind turbine blades, etc. The bending actuators and microhinges of microrobots constructed from CFRP materials also require inclined holes. Laser percussion drilling techniques produce a high aspect ratio of high-resolution inclined holes. The geometrical deviation of the laser-drilled hole is usually evaluated in terms of hole circularity and hole taper. No literature is available for inclined hole drilling of the above two types of FRPs using infrared (IR) laser. In this paper, the thickness of each FRP is taken as 1, 3 and 5 mm, respectively. The one-parameter-at-a-time (OPAT) method was used to analyze the individual effects of laser input parameters, such as pulse current, pulse width, assist gas pressure, workpiece thickness, and incidence angle, on output performance characteristics of hole circularity at top (THC), bottom (BHC), and taper (TH) during laser percussion-inclined drilling with millisecond (ms) pulsed Nd: YAG. Pulse current of 200–225A or 275–300A does not affect THC at a zero-degree angle of incidence. A greater pulse current (300 A) is produced during inclined drilling at 100∘ and 200∘. SEM/EDX investigation reveals hole surface and material composition. [ABSTRACT FROM AUTHOR]

This paper aims to provide a method for improving the tribological properties of 316L stainless steels in seawater. During the experimental process, laser texturing technology was used to create biomimetic micro-textures inspired by turtle shell patterns on the 316L stainless steel surfaces. Then, CrAlSiN coating was deposited on the textured surface using the physical vapor deposition (PVD) technique, allowing us to study the frictional properties of the samples in both atmospheric and seawater environments. The results showed that, compared to polished 316L stainless steel, the specimens treated with micro-texture and CrAlSiN coating exhibited a reduction in wear rate by 52.1% and 71.8% under atmospheric and seawater friction conditions, respectively. Under atmospheric friction conditions, the micro-textures had a limited effect on reducing the friction of the 316L stainless steel substrate. However, the CrAlSiN coating, due to its excellent mechanical properties, significantly improved the wear resistance of the 316L stainless steel. Under seawater friction conditions, the continuous CrAlSiN coating played a role in reducing 316L stainless steel wear and seawater corrosion. At the same time, the micro-textures acted as reservoirs for wear debris and seawater, forming a more stable seawater lubricating film and reducing the friction coefficient. Therefore, the synergistic effect of the CrAlSiN coating and biomimetic micro-textures demonstrated remarkable improvement in the tribological performance of 316L stainless steel in seawater environments. [ABSTRACT FROM AUTHOR]

This paper describes the pulsed Nd:YAG laser machining characteristics on 6351 aluminum reinforced with silicon carbide (SiC) and boron carbide (B4C) particles. The composites are prepared using stir casting route by varying the weight percentage of B4C (0, 5, and 10 wt.%). During experimentation, the traverse speed (5, 15, and 30 mm/s) and the laser pulse frequency (5, 9, and 15 kHz) are considered to evaluate the groove width. The results reveal that the lower pulse frequency produced poor groove surface quality. Higher thermal energy dissipation at lower traverse speed may also result in the formation of recast layer and heat-affected zone. This is evident from the microscopic image and the EDS analysis. Thus, the optimum condition (composite with 10 wt.% B4C machined at 30 mm/s and 15 kHz) to achieve minimum grove width with improved surface morphology is identified by desirability analysis. Additionally, the regression model is developed to predict future values (R 2 at 91.86% and R 2 (adj) at 87.55%). Finally, the probability plot confirms the effectiveness of the proposed model at 95% confidence level. [ABSTRACT FROM AUTHOR]

The degradation control of implants has now become a most critical factor for investigation. The rapid degradation or uncontrolled degradation of metals causes allergic reaction and implants failure. The biocompatibility and biodegradability of biometals are essential properties for the development of bioimplants. The biodegradation is the chemical reaction of implants metal with the surrounding body fluids. The gradual dilution of metal oxide with the body fluid is considered as a degradation. Magnesium, zinc, and iron metals are biodegradable metals. The biodegradability of as-cast metals is not capable of fulfilling the need of patients, therefore, degradation of implants is required to be in control. Many more research articles have been published on improvement of corrosion resistive implant surface by coating, passivation oxide layer, plasma spraying, electropolishing, blasting, chemical etching, laser treatment, heat treatment, severe plastic deformation (SPD), alloying, and development of surface composites. This paper critically reviewed the surface modification and surface composite fabrication techniques to improve the biodegradability, biocompatibility, and strength of implants. [ABSTRACT FROM AUTHOR]