Surface Of Metallic Materials Research Articles

Исследование гидрофильности поверхности металлических материалов, модифицированных ультрафиолетовым лазерным излучением

Introduction. Surface modification using laser radiation is a promising direction in the field of creating new technologies for treatment metal materials, including those for medical purposes. The ability of lasers to change the surface characteristics of a material and, consequently, its interaction with the environment has attracted great interest among researchers. Despite numerous recommendations for the use of laser surface treatment, there is still lack of systematic and detailed studies on the influence of parameters on the structural-phase state and properties of the modified surface, especially concerning ultraviolet laser exposure. The purpose of this work is to study the hydrophilicity of the surface of TiNi alloy and stainless steel after UV laser treatment. Materials and methods of the study: experimental samples made of TiNi (TN-10) alloy and 12KH18N9T (AISI 321) stainless steel were locally (beam diameter 0.5 cm) exposed to a solid-state Nd:YAG laser at the wavelength of 266 nm, with a pulse duration of ~ 5 ns, and pulse repetition rate of 10 Hz. The material was exposed to a constant output radiation energy density of 0.1 J/cm2, with a change in the exposure duration from 10 to 600 s. Before and after UV laser treatment, the wettability of the material surface and free surface energy were determined. The structure, elemental and phase composition, and surface topography of TiNi and steel were studied using scanning electron microscopy with the determination of the elemental composition by energy-dispersive spectroscopy, X-ray phase analysis, and profilometry. Results and discussion. Ultraviolet laser treatment of the surface of TiNi alloy and steel samples leads to an increase in their hydrophilicity. In the initial state, the contact angle of wetting is ≈75° for both materials, and after ultraviolet laser treatment it decreases to ≈11-13° for TiNi and to ≈22° for steel. The phase composition of steel does not change during laser treatment, and phases belonging to oxides are recorded on the surface of TiNi after 420 seconds of treatment. Ultraviolet laser treatment of TiNi alloy and steel leads to an increase in free surface energy, a change in the ratio of its components (a decrease in the dispersed component and a significant increase in the polar component), an increase in the oxygen content on the surface of both materials. With long laser exposure times (more than 300 seconds), microcracking occurs on the surface of the processed material, leading to an increase in roughness. The change in the surface topography (roughness) of TiNi alloy does not have a noticeable effect on the wettability of the surface of metal materials, and for steel samples, there is an insignificant tendency to reduce the contact wetting angle with increasing roughness. The degree of hydrophilicity of metal materials, characterized by the contact wetting angle, increases with an increase in the duration of laser exposure due to saturation of the surface with free oxygen and an increase in free surface energy (its polar component). Based on the studies, it can be concluded that ultraviolet laser treatment is an effective way to change the wettability of metal materials.

Research status and prospects of the fractal analysis of metal material surfaces and interfaces

Research status and prospects of the fractal analysis of metal material surfaces and interfaces

Enhanced electrical and mechanical properties of graphene/copper composite through reduced graphene oxide-assisted coating

Modifying the surface of metallic materials with graphene (Gr) holds significant potential for achieving high electrical conductivity in metal-based composites, leveraging the synergistic effect of the high carrier concentration in metals and the high carrier mobility of Gr. However, the strong van der Waals forces and large specific surface area of Gr sheets often lead to agglomeration in slurrys, adversely affecting the arrangement of Gr layers within the coating structure. In this study, we introduce reduced Gr oxide (rGO) into the Gr slurry to enhance the electrostatic stability and dispersion of Gr sheets through π-π interactions. By precisely controlling the composition of the coating, a compact, low-roughness coating was prepared on the surface of the copper (Cu) wire. The fabricated Gr/rGO/Cu composite wire exhibited a high conductivity of 104.2% IACS, with a tensile strength of 266.1 MPa and the elongation of 36.3%, respectively. This study demonstrates that the addition of rGO improves the dispersibility of Gr in the slurry, leading to a more compact and effective composite structure. The Gr/rGO/Cu composite wires exhibit superior electrical and mechanical properties, making them promising candidates for high-performance applications in electrical and electronic industries.

Recent Progress in Ultrasonic Surface Rolling: A Comprehensive Overview

Metals and their alloys have found extensive applications in numerous fields. Various surface modification techniques have received significant attention for their potential to improve the adaptability of materials to complex environments. One such technique, the ultrasonic surface rolling process (USRP), introduces a deformation layer by applying static stress and dynamic impacts to the surface of metallic materials. During USRP treatment, remarkable beneficial compressive residual stresses (CRS) and hardened layers are induced and, simultaneously, the surface finish of the material is improved. These modifications not only effectively suppress the initiation and propagation of fatigue cracks but also significantly enhance the mechanical properties, wear, and corrosion resistance of the materials, thereby greatly prolonging the service life of structural components. The review starts with the mechanisms of USRP, discussing grain refinement, control of surface roughness, and the introduction of beneficial CRS. Subsequent sections provide a comprehensive analysis of how these modifications impact material properties, encompassing hardness, plasticity, fatigue, wear, and corrosion resistance. Furthermore, it introduces the latest advancements in USRP technology, including thermal/electric pulse‐assisted USRP, its integration with other surface treatment methods, and its applications and prospects across various fields.

Research on metal surface specular removal algorithm based on unsupervised learning

The highlights on the surface of metal materials can seriously destroy the continuity of the image, produce certain false edges, and cause the texture details in the highlights area to weaken or even disappear, which interferes with the subsequent operations such as surface region segmentation and defect detection. Aiming at the low efficiency, high loss, easy distortion and difficult calibration of metal highlight data, an unsupervised perceptual enhancement network model based on the convolutional neural network (CNN) is proposed. Firstly, the method of generating antagonism is used to generate a large number of metal images with high-light feature information, which is used to increase the number of high-light metal image data sets in the training set. Secondly, a detail enhance model(DEM) and a color enhance model(CEM) are introduced into the context aggregation network to improve the feature detail retention rate in the low resolution weight graphs. Finally, the multi-scale structural similarity function is used to replace the original structural similarity function to solve the insensitive detail when the image size is too large. Experiments show that comparing with other multi-exposure image fusion models, the present model can improve the evaluation index of mutual information and average gradient of fused images by about 10%, and can retain more texture feature information.

Influence of Corrosion on Thermo-Mechanical Contact Fatigue in Rolling Conditions with Low Amplitude Sliding

The paper presents some aspects concerning mechanical contact fatigue and corrosion wear and the links of these two kinds of wear in the common deterioration of the contact layer. The surface state, for both presented areas, is analyzed using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) in order to confirm the double action of corrosion and wear during the experimental test. 2 and 3D insights were taken from the worn area, corrosion compounds were identified and analyzed. Linear and cyclic potentiometry were performed on the base materials after the OCP was established in salt solution. When the level of the thermal and the mechanical stress are located at the same depth under the contact surface the resulting stress is greater and has the opportunity to develop the first crack to the surface. The metallic material surface presents a double type of corrosion: one based on oxidation and the other one based on oxidation plus wear (tribo-corrosion), the difference is being given by the material quantity and type involved.

Magneto-acoustic Fusion Sensing for Surface and Subsurface Defect Differentiation in the Ferromagnetic Material

The conventional periodic permanent magnet (PPM) shear horizontal (SH0) guided wave electromagnetic acoustic transducer (EMAT) has a good detection capability for defects on both the surface and subsurface of the material. However, it is difficult to distinguish between surface and subsurface defects in the material using only the amplitude of the defect echo. In this paper, SH0 guided wave is excited using the SH0 guided wave EMAT with PPM configuration, which is used to achieve the detection and evaluation of defects on the surface and subsurface of ferromagnetic metal; on the other hand, the local magnetic field perturbation (MFP) effect of the PPM configuration on ferromagnetic material is fully exploited to achieve the identification of surface defects by picking up the MFP of the material at the defects. The proposed magneto-acoustic fusion effect sensor has an improved spatial magnetic field at both the mechanical construction and the magnetic sensor compared to the traditional magnetic flux leakage (MFL) detection method. Both simulation and experiment show that the proposed magneto- acoustic fusion effect sensing method based on the PPM configuration is capable of detecting the defects on the surface and subsurface of metal material, while the MFP effect in the fusion sensor can be used to help differentiate between the surface and subsurface defects in the material.

A REVIEW OF PREDICTIVE MAINTENANCE APPROACHES FOR CORROSION DETECTION AND MAINTENANCE OF MARINE STRUCTURES

Corrosion is a natural phenomenon that deteriorates and damages the surface of metallic material. Over time, the surface of the material deteriorates due to electrochemical reactions with the surrounding environment. If corrosion is not identified early on, it can become a major financial burden for industries, costing billions of dollars. Despite swift technological developments, preventing and maintaining corrosion progression with reactive maintenance remains difficult. Due to that, predictive maintenance has been developed to predict the deterioration, degradation, and fault over the remaining useful life of the material by using real-time data, historical data, simulation, modelling, and failure probability. Predictive maintenance allows inspectors to monitor the health and predict the corrosion level of the material. However, it is hard to predict the unexpected degradation of the material from the developed prediction model without considering the harsh environment and other external factors. Hence, there is a need to investigate these problems and their effect on predictive maintenance for corrosion detection and maintenance. Therefore, this paper reviews and compares the state-of-the-art predictive maintenance solutions developed to solve corrosion issues in various applications, industries, and academic research. The challenges and opportunities for the predictive maintenance application of corrosion detection and maintenance are also presented. This review will provide new and additional knowledge that can be used to develop prediction models for corrosion detection and maintenance, which will help prevent unexpected failures.

Review on numerical simulation of ultrasonic impact treatment (UIT): Present situation and prospect

Ultrasonic Impact Treatment (UIT) is a surface treatment method that uses ultrasound to create high-frequency, high-intensity impact loads on the surface of metallic materials to improve material properties and durability. The current state of research on the numerical simulation of UIT is reviewed in this paper. Firstly, the working principle of UIT strengthening is introduced, which includes the application of high-intensity UIT to the surface of metallic materials. The UIT strengthening technology has achieved significant success in the industrial field, resulting in plastic deformation, surface compression and residual stress, thereby significantly improving material properties. Secondly, the influence of UIT on the microstructure is reviewed. It is found that the grain refinement and dislocation are successfully predicted by finite element simulation and other methods. The influence of UIT on residual stress is reviewed. It is found that UIT can effectively transform harmful tensile stress into compressive stress, and it has been found that it can be used to guide the industrial practice of welding, laser cladding and additive manufacturing. In general, UIT technology shows important potential in metal material processing, which is of great significance for improving material properties and promoting industrial practice.

Investigation and analysis of a sustainable agro-based nanocoating on surface of metallic materials

In this study, nanotechnology was used to develop a coating from agricultural waste. Banana peels underwent various chemical processes, nanoparticles were developed and tests were conducted to validate it. The metal samples used for coating application were made of mild steel which is used to produce a large percentage of metal parts in the industry and was selected for this research project due to that reason. The metals were cut into 50 mm x 50 mm and 50 mm x 30 mm. The sample coatings included a control coating which was used as the yardstick to know the effects of the nano coating applied which contained various concentrations of nanoparticles showed results that were more favorable than the coatings that were applied without nanoparticles contained in them. Qualitative analysis of the coated metal samples A to G showed that sample E which had 7.24 grams of nanoparticles contained in it had the highest amount of hardness while sample A which was control coating possessed the least hardness amount. The abrasion test of the samples revealed that sample D which had 21.72 grams of nanoparticles contained in it possessed the highest weight of coating before and after the abrasion test

Wear and corrosion behavior of TiC and WC coatings deposited on high-speed steels by electro-spark deposition

Abstract Electro-spark deposition (ESD) is one of the most effective methods for improving the surfaces of metallic materials by applying ceramic-based cermet coatings. In this study, TiC and WC coatings were deposited on the surface of AISI M2 high-speed steel using the ESD method. Subsequently, the coated surfaces were examined through microstructure, phase structure, microhardness, friction, wear, and electrochemical corrosion tests, and compared with untreated AISI M2 steel. The TiC and WC phase coatings obtained with ESD resulted in a significant improvement, with hardness levels exceeding four times that of AISI M2 steel, leading to reduced wear volume losses and friction coefficients. Furthermore, the cermet coatings formed on the surface exhibited 2–3 times improvement in corrosion resistance due to their lower conductivity. This study demonstrates that WC coatings may offer a more effective solution for enhancing the wear resistance of AISI M2 steel, while TiC coatings could be more effective in improving corrosion resistance.

Study on the properties of sodium bismuth titanate coating prepared by supersonic plasma spraying

In order to realize the preparation of environmentally friendly piezoelectric ceramic coatings on the surface of metallic materials, sodium bismuth titanate (Bi0.5Na0.5TiO3, BNT) ceramic coatings were prepared by supersonic plasma spraying. The surface morphology, cross-sectional morphology, phase structure, and elemental valence variations of the BNT coating were examined, as well as the dielectric and ferroelectric properties of the BNT coating. The results show that the coating has a good quality and a single perovskite structure. The dielectric constant was stable at about 425 and the dielectric loss was stable at about 0.06 when the test frequency reached 200 kHz. The coating exhibits good hysteresis lines under different applied electric fields. When the applied electric field was 40 kV/cm, the remnant polarization value of the prepared coating was 11.47 µC/cm2. It can be seen that the BNT piezoelectric coating prepared by supersonic plasma spraying has good ferroelectric and dielectric properties, which lays a solid foundation for in-situ monitoring of environmentally friendly lead-free BNT piezoelectric coating.

Surface Protection Technology for Metallic Materials in Marine Environments.

As the demand for the development and utilization of marine resources continues to strengthen, the service requirements for advanced marine equipment are rapidly increasing. Surface protection technology has become an important way of solving the tribological problems of extreme operating conditions and improving the safety performance of equipment by imparting certain special properties to the surface of the material through physical, chemical or mechanical processes to enhance the ability of the material to withstand external environmental factors. Combined with the extremely complex characteristics of the marine environment, this paper describes the commonly used surface protection technologies for metal materials in the marine environment. Research on surface texture was summarized under different surface reshaping technologies, as well as processes and coating materials under different surface modification technologies. Combined with the existing research progress and development trends of marine metallic materials, the surfaces of metal materials under the marine environment protection technology foreground are prospected and provide a reference for the improvement of equipment performance in extreme marine environments.

Removal mechanism of Hydroides fouling on high-strength steel in the marine environment during nanosecond pulsed laser cleaning

The surface of metal materials will be contaminated by marine organisms when serving in the marine environment, which seriously affects the service life of the materials, and must be cleaned regularly. The Hydroides fouling on the surface of 30Cr3 high-strength steel was taken as the object to be cleaned; the cleaning quality at different laser fluences was studied; the desorption behavior and the characteristics of spectral and acoustic signals during laser cleaning were analyzed; and the removal mechanism of Hydroides fouling on the surface of high-strength steel was summarized. The results show that the cleaning effect of nanosecond pulsed laser on Hydroides fouling increases with the increase of laser fluence, and the laser fluence of 9.95 J/cm2 can be used to clean the Hydroides fouling with the maximum diameter of 1.62 mm completely with little damage to the substrate. The removal mechanism of Hydroides fouling is the inverse bremsstrahlung mechanism. In the process of cleaning, the surface fouling is partially vaporized and ionized into high-temperature plasma under the action of pulsed laser. The laser energy is absorbed through inverse bremsstrahlung absorption to form shock waves to compress the surface, which leads to cracks on Hydroides fouling. When the surface compressive stress is released, the Hydroides fouling is removed from the surface, and the removal effect increases with the increase of laser fluence.

Depth-resolved and time-resolved investigations of Er2O3 ceramics after static lithium corrosion by using LIBS at different pressures

Liquid metal lithium can cause severe corrosion on the surface of fusion reactor blankets and first-wall metal materials. Oxidized erbium ceramic has been widely studied as a candidate material for the self-cooling blanket system of tokamak fusion reactors. In this study, time-resolved picosecond laser-induced breakdown spectroscopy (ps-LIBS) was used to investigate the time evolution process of laser-induced plasma (LIP) of Er2O3 samples in air at different pressures. The pressure-time windows with high signal-to-background ratio and high signal-to-noise ratio under LTE conditions were determined. The composition depth distribution of the Er2O3 ceramic after static corrosion by lithium was analyzed. The number of laser pulses were linearly proportional to the laser ablation depth as measured by a three-dimensional profilometer. As the number of pulses increased, the relative intensities of the 610.353 nm and 812.645 nm characteristic lines of the corroding element Li gradually decreased, while the relative intensities of the 405.547 nm and 405.951 nm characteristic lines of the base element Er gradually increased. The laser pulse number at which the relative peak intensities of Er and Li reached a steady state showed a trend of first increasing and then decreasing with increasing pressure. In addition, the results of laser ablation depth under different environmental pressures indicated that the depth resolution of the analysis of anti-corrosion Er2O3 ceramic materials can be controlled by the environmental gas pressure.

SCPNet-based correction of distorted multi-spots for three-dimensional surface measurement of metal cylindrical shaft parts.

Metal cylindrical shaft parts are critical components in industrial manufacturing that require high standards for roundness error and surface roughness. When using the self-developed multi-beam angle sensor (MBAS) to detect metal cylindrical shaft parts, the distorted multi-spots degrade the measurement accuracy due to the nonlinear distortion caused by the metal material's reflective properties and surface roughness. In this study, we propose a spot coordinate prediction network (SCPNet), which is a deep-learning neural network designed to predict spot coordinates, in combination with Hough circle detection for localization. The singular value decomposition (SVD) model is employed to eliminate the tilt error to achieve high-precision, three-dimensional (3D) surface reconstruction of metal cylindrical shaft parts. The experimental results demonstrate that SCPNet can effectively correct distorted multi-spots, with an average error of the spot center of 0.0612 pixels for ten points. The proposed method was employed to measure metal cylindrical shaft parts with radii of 10 mm, 20 mm, 35 mm, and 50 mm, with resulting standard deviation (STD) values of 0.0022 µm, 0.0026 µm, 0.0028 µm, and 0.0036 µm, respectively.

Structural and mechanical properties of magnetron-sputtering-deposited Ta- and Al- based coatings – a comparative analysis

A comprehensive evaluation of the structure and the nano-mechanical characteristics of single and two-layer nano-structured coatings AlN/Al2O3, TaN/Ta2O5 grown on the surface of metallic materials. The formation of a two-layer structure improves the mechanical and tribological properties of the coating-substrate system, such as the plastic deformation resistance and anti-wear performance. The results indicate that the proposed two-layer nanostructured nitride-oxide coatings based on aluminum and tantalum are promising candidates for biomedical applications.

Role of length-scale in machine learning based image analysis of ductile fracture surfaces

Recent advancements in machine learning (ML) techniques have opened up new opportunities for using image analysis to solve materials science and engineering problems. In this work, we have used an ML-based workflow to classify the fracture surfaces of dual-phase steels subjected to different stress states. This task is not straightforward, as the ductile fracture surfaces of many metallic materials exhibit similar features, such as dimples. The ML-based workflow uses a pre-trained convolution neural network in unsupervised mode to extract image features, which are then reduced in dimensionality using principal component analysis. Next, images are clustered and classified using K-Means and K-Nearest Neighbors algorithms, respectively. Our results show that the accuracy of the ML-based technique is sensitive to the length-scales of the fracture surface images, and the critical length-scale corresponding to the maximum accuracy depends on the typological categories being classified. A physical interpretation of the critical length-scales associated with the fracture surface images is provided through quantitative fracture surface roughness analysis. Our work demonstrates the potential of using unsupervised ML-based techniques for fractography of ductile materials, especially for typological classification. More importantly, it emphasizes the importance of length-scales in image analysis in materials science and engineering.

Laser Shock Wave Surface Processing Possibilities of Structural Materials

Laser shock wave treatment is a newest effective tool for modifying material properties. Irradiation of materials with a laser in the Q-switched mode in different mediums can change the relief and surface structure of the irradiated material. Images of the surfaces of metallic materials under different irradiation conditions were obtained with the help of a scanning electron microscope. It is shown that the energy of the laser pulse and the transparent condensed medium through which the processing is carried out play an important role on the surface structuring. The possible causes of periodic relief are explained.

A radiative cooling, anti‐corrosion multifunctional composite coating derived from Jatropha (Jatropha curcas L.) oil

AbstractHere, a new application from Jatropha (Jatropha curcas L.) oil was successfully proposed to develop a multifunctional composite coating using Jatropha oil (JO) as a raw material to replace traditional non‐renewable chemical materials. Here, a new application of Jatropha oil is proposed to develop a multifunctional composite coating using Jatropha oil as a raw material instead of traditional non‐renewable chemical materials. To achieve this goal, Jatropha oil first needs to be made into refined Jatropha oil (RJO) by degumming, deacidification, decolorization, and deodorization. The RJO was then subjected to epoxidation to obtain epoxidized Jatropha oil (EJO), and the optimal epoxidation conditions were explored. Finally, EJO was synthesized as acrylate and barium sulfate (BaSO4) was added as inorganic filler to prepare a composite coating. The results showed that the thermal decomposition temperature of the composite coating was as high as 451°C, and the composite coating showed the best mechanical properties when the filling amount of BaSO4 reached 40%. The composite coating has a reflectivity of over 80% in the UV region and can reach a contact angle of 108 ° with excellent hydrophobicity, which can play a self‐cleaning role. In addition, the composite coating is also immersed in acid and alkali solution for 30 days, it has less mass loss and shows excellent acid and alkali resistance, which can play the role of anti‐corrosion. The composite coating can be attached to the surface of wood, glass, metal, plastic, and other materials to provide protection for the materials, which has good application prospects. This pioneering work provides an opportunity to promote JO with depressed application market in industrial production.