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Atmospheric plasma etching (APE) has been used to texture Si surfaces due to anisotropic material removal capability. Controlling features and size of the light-trapping structure are keys to improving the reflection performance of silicon (Si) solar cells, which need to fully understand the interfacial etching behavior and the microscopic topography formation mechanism of the Si surface. In this study, microwave plasma with a temperature below 100 °C is employed to investigate the dependence of microstructure evolution on the O/F atom ratios in plasma. The results show that as the O/F atom ratios increase, the microstructure of the Si surface changes from square opening pits to spherical opening pits. High-resolution transmission electron microscopy and x-ray photoelectron spectroscopy analyses indicate that the exciting F atoms dominate the orientation-selective etching process, causing the formation of square opening pits. The CFx and C2 radicals induce the generation of the Si interface reactive layer, resulting in the occurrence of amorphous layers and termination of the non ⟨111⟩-crystal face in APE. The exciting O atoms preferentially occupy the active site of Si surfaces, causing the isotropic etching and then the formation of spherical opening pits. In addition, the richer O atoms will weaken the anisotropic etching ability of F atoms, resulting in the etched surface trends' flattening. The insight into anisotropic etching behavior and topography formation mechanism of the silicon surface textured by atmospheric plasma is valuable for developing a new texturing approach to silicon solar cells. [ABSTRACT FROM AUTHOR]

A systematic review and meta-analysis of sputter yield data for xenon ions normally incident on graphite at energies below 2000 eV was undertaken to identify systematic errors, determine the best model parameter values to represent yield as a function of energy, quantify uncertainty, and determine if the data support differences in yields for different types of graphite. A critical examination of the 11 published data sets for high density graphite, pyrolytic graphite, and amorphous carbon showed that, in general, they were carefully controlled to minimize errors. The most significant quantifiable systematic errors were those caused by the neglect of doubly charged ions, chemical erosion, and the impact of secondary electron emission on ion flux measurements. The effects of gas uptake and outgassing on mass loss measurements and unrepresentative surface textures may have biased other experiments, but these effects could not be quantified. The semi-empirical Eckstein model for yield as a function of energy was fit to data for the three graphite types using a hierarchical Bayesian statistical model, producing recommended fit parameters and probability distributions representing uncertainty in yields. The results showed that differences in yield for high density graphite and pyrolytic graphite were not statistically significant. Apparent differences in yield for amorphous carbon disappeared when the single data set available for energies below 150 eV was corrected for reasonable values of double ion content. Recommended procedures to avoid systematic errors and additional experiments and modeling to fill in gaps in our understanding are included. [ABSTRACT FROM AUTHOR]

Purpose: This investigation aimed to assess the impact of additive manufacturing-generated surface textures on zirconia bond strength. Materials and Methods: Zirconia samples (n = 144) fabricated using digital light-processing (DLP) technology were categorized into 6 groups according to the type of surface conditioning (group NN: no designs, no air abrasion; group NY: no designs, with air abrasion; group GN: groove designs, no air abrasion; group GY: groove designs with air abrasion; group HN: hexagon grid, no air abrasion; group HY: hexagon grid, with air abrasion). Composite resin cylinders were cemented to the treated zirconia surfaces with dual-curing, self-adhesive resin cement (Clearfil SA Luting). The shear bond strength (SBS) was tested after water storage for 3 days or 3 days with an additional 10,000 thermocycles. Results: The zirconia samples fabricated using DLP technology have high accuracy. The SBS of the NY, GY, and HY groups did not significantly differ after 3 days, and neither did the SBS of the NN, GN, and HN groups. The NN, NY, and HY groups exhibited reduced SBS compared to their initial values following artificial aging, while the SBS of the remaining three groups were not diminished. The GY group obtained the highest SBS value after aging. Conclusion: Printing grooves with air abrasion can improve the bond strength. [ABSTRACT FROM AUTHOR]

Hydrophobicity has proven fundamental in an inexhaustible amount of everyday applications. Material hydrophobicity is determined by chemical composition and geometrical characteristics of its macroscopic surface. Surface roughness or texturing enhances intrinsic hydrophilic or hydrophobic characteristics of a material. Here we consider crystalline surfaces presenting molecular-scale texturing typical of crystalline porous materials, e.g., metal-organic frameworks. In particular, we investigate one such material with remarkable hydrophobic qualities, ZIF-8. We show that ZIF-8 hydrophobicity is driven not only by its chemical composition but also its sub-nanoscale surface corrugations, a physical enhancement rare amongst hydrophobes. Studying ZIF-8's hydrophobic properties is challenging as experimentally it is difficult to distinguish between the materials' and the macroscopic corrugations' contributions to the hydrophobicity. The computational contact angle determination is also difficult as the standard "geometric" technique of liquid nanodroplet deposition is prone to many artifacts. Here, we characterise ZIF-8 hydrophobicity via: (i) the "geometric" approach and (ii) the "energetic" method, utilising the Young–Dupré formula and computationally determining the liquid–solid adhesion energy. Both approaches reveal nanoscale Wenzel-like bathing of the corrugated surface. Moreover, we illustrate the importance of surface linker termination in ZIF-8 hydrophobicity, which reduces when varied from sp3 N to sp2 N termination. We also consider halogenated analogues of the methyl-imidazole linker, which promote the transition from nanoWenzel-like to nanoCassie–Baxter-like states, further enhancing surface hydrophobicity. Present results reveal the complex interface physics and chemistry between water and complex porous, molecular crystalline surfaces, providing a hint to tune their hydrophobicity. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HA) or bioceramic-based coatings on stainless steel (SS) 316L significantly enhance the biofunctionality of the base material's surface. However, HA's low thermal conductivity and brittleness limit its effectiveness as a coating material. This study investigates HA coating on SS 316L using electric discharge machining (EDM) with varying discharge energies and powder concentrations. Surface morphology, elemental composition, and phase analysis of untreated and coated samples were characterised using field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX), and X-ray diffraction (XRD). The results demonstrate that the HA-assisted EDM process creates a coating comprising biocompatible oxides, phosphates, carbides, and intermetallic compounds. The coating exhibits a thin resolidified layer of 10.74 μm, characterised by redeposited spherical debris, shallow cavities, and a surface texture of 2.688 μm. The layer's hydrophilic nature is confirmed by a minimum contact angle of 47.68°. Taguchi analysis indicates that the machining rate is optimised at an HA powder concentration of 16 g/l, with peak current and HA powder concentration being the most influential parameters affecting resolidified layer thickness, surface texture, and wetting angle. The research intends to motivate SS 316L medical device manufacturers to implement the HA-assisted EDM process for bioimplant's dual machining and coating. [ABSTRACT FROM AUTHOR]

Because surface texture is nearly the sole indicator of pavement functional properties and highly correlated with critical operational characteristics of roadways like traffic noise and safety, the change in pavement surface texture because of traffic loadings and environment has to be evaluated routinely. There are numerous direct or indirect evaluation techniques in the market. However, most of these methods have some limitations like requiring lane closure or being expensive. In this study, a 2D image processing method was established to estimate the surface mean texture depth (MTD) of chip sealed pavements. We produced chip sealed pavement samples in the laboratory with different aggregate type, shape, and size ranging between 2 and 19 mm to cover wide range of live conditions. Two well-known conventional test methods, Sand Patch (SP) and Hydrotimer (HT), were used to determine MTDs of chip seal samples. Subsequently numerous photos were taken on surface of the samples with a camera for 2-D image processing that was done based on surface void ratio (SVR) approach. With the image processing, SVR of all samples were determined. At the point of whether there is a relationship or not, correlation analysis was made between the MTDs obtained with SP and HT and the data obtained by SVR approach with the artificial neural network method. The results show that the proposed SVR approach construed on 2D image processing method can be a reliable alternative to evaluate the surface texture of pavements. [ABSTRACT FROM AUTHOR]

Engineered Cementitious Composites also known as Strain‐hardening cementitious composites (SHCCs) has unique cracking patterns like cracks that have tiny widths and showcase high density. All of this makes it difficult and laborious to compute crack parameters from crack patterns. Unfortunately, this is an essential part of assessing durability and micromechanical modeling. SHSnet is developed to perform end‐to‐end semantic segmentation of SHCC cracks. SHSnet is efficient, attention based deep encoder‐decoder network with large receptive field. Loss function based on Tversky function were used for training the model. SHSnet with loss function shows promising result with mPrecision, mF1Score and mIoU of 0.87, 0.84 and 0.83 respectively for complex SHCC cracks while requiring at least an order of fewer computational parameters than those in the literature. An image processing unit is then used to estimate the width, number, and length of the cracks from the segmentation mask. Test results show that the computed crack parameters with SHSnet are exactly the same as that computed with an optical microscope but require ~100× less time. Results demonstrate that SHSnet works equally well in SHCCs with different surface textures, crack density, and widths; the final result was far superior to a conventional technique. This technique also shows promising results in an automatic evaluation of crack parameters relevant to durability and visualizing crack patterns even in the presence of artifacts during progressive testing. The results also demonstrate the necessity to accurately and densely calculate crack length and maximum crack width; else the durability results are expected to be significantly more conservative than the actual value. [ABSTRACT FROM AUTHOR]

This study investigates the joining of dissimilar materials, specifically galvannealed advanced high‐strength steel (AHSS) and glass fiber‐reinforced polyamide 6 (PA 6) to achieve lightweight automotive. AHSS and PA 6 are widely used in the automobile industry; however, a direct joining of those two materials is difficult owing to their great difference in physical properties. Therefore, laser surface texturing (LST) and plastic injection molding are adopted to join AHSS and PA 6, which can create a strong mechanical interlock between AHSS and PA 6, resulting in an excellent joint strength compared to other joining techniques. The effects of LST parameters (groove depth and hatch distance) and injection molding temperatures on the joint strength are examined. The maximum AHSS‐PA 6 joint strength is measured at 72.3 MPa. Additionally, the microstructure and mechanical properties of recast, which develops over the original metal surface by melting and resolidifying, are analyzed. Compared to the base metal, the recasts exhibit higher hardness due to smaller grain sizes. PA 6 fills the laser‐textured grooves and spaces between the recasts, acting as a mechanical interlock that enhances joint strength under tensile shear testing. [ABSTRACT FROM AUTHOR]

The classification of ablation images holds significant practical value in thermal protection structures, as it enables the assessment of heat and corrosion resistance of composites. This paper proposes an image‐based deep learning framework to identify the surface texture of carbon/phenolic composites ablative images. First, ablation experiments and collection of surface texture images of carbon/phenolic composites under different thermal environments were conducted in an electric arc wind tunnel. Then, a deep learning model based on a convolutional neural network (CNN) is developed for ablative image classification. The pre‐trained network is ultimately employed as the input for transfer learning. The network's feature extraction layer is trained using the ImageNet dataset, while the global average pooling addresses specific classification tasks. The test results demonstrate that the proposed method effectively classifies the relatively small surface texture dataset, enhances the classification performance of ablative surface texture with an accuracy of up to 97.6%, and exhibits robustness and generalization capabilities. Highlights: The paper proposes a new deep learning classification method for ablative images.A model highly sensitive to small and weak features is built.Transfer learning and data enhancement techniques are introduced into classification. [ABSTRACT FROM AUTHOR]

The inherent limitations of native starch considerably restrict its applications in the food industry. To enhance its processing properties, Arenga pinnata (Wurmb.) Merr. starch (APS) was subjected to dual modification with low levels of sodium trimetaphosphate (0%, 1%, and 3%) and chitosan (1%) to investigate its physicochemical, thermal, pasting, and in vitro digestibility. The dual modification of APS significantly increased the degree of cross‐linked (CLD) to 84.69%, resulting in a rougher surface texture. This process led to the formation of phosphate bonds, the weakening of hydrogen bonds, and a decrease in relative crystallinity, all while preserving the starch's crystalline structure. Additionally, the modification impeded paste formation, reduced swelling power, and lowered pasting enthalpy, while increasing the content of slowly digestible starch and resistant starch. These findings provided a basis to enhance the functional properties of starch‐based materials, which could be applied to improve the texture and stability of food products such as sauces, dressings, and desserts in the food industry. [ABSTRACT FROM AUTHOR]

Tactile sensors play a critical role in robotic intelligence and human-machine interaction. In this manuscript, we propose a hybrid tactile sensor by integrating a triboelectric sensing unit and a capacitive sensing unit based on porous PDMS. The triboelectric sensing unit is sensitive to the surface material and texture of the grasped objects, while the capacitive sensing unit responds to the object's hardness. By combining signals from the two sensing units, tactile object recognition can be achieved among not only different objects but also the same object in different states. In addition, both the triboelectric layer and the capacitor dielectric layer were fabricated through the same manufacturing process. Furthermore, deep learning was employed to assist the tactile sensor in accurate object recognition. As a demonstration, the identification of 12 samples was implemented using this hybrid tactile sensor, and an recognition accuracy of 98.46% was achieved. Overall, the proposed hybrid tactile sensor has shown great potential in robotic perception and tactile intelligence. [ABSTRACT FROM AUTHOR]

With the variety of fibers and fabrics, the studies of the surface structure of the textile yarns, the weave fabric, and their surface wettability are still potential factors to improve and optimize the fog harvesting efficiency. In this work, inspired by the fog harvesting behavior of the desert beetle dorsal surface, a wavy–bumpy structure of post-weave yarn (obtained from woven fabric) was reported to improve large droplet growth (converge) efficiency. In which, this study used tetrabutyl titanate (Ti(OC4H9)4) to waterproof, increase hydrophobicity, and stabilize the surface of yarns and fabric (inspired by the feather structure and lotus leaf surface). Moreover, PDMS oil was used (lubricated) to increase hydrophobicity and droplet shedding on the yarns (inspired by the slippery surface of the pitcher plant) and at the same time, enhance the fog harvesting efficiency of the warp yarn woven fabric (Warp@fabric). In addition, a three-dimensional adjacent yarn structure was arranged by two non-parallel fabric layers. The yarns of the inner and outer layers were intersected at an angle decreasing to zero (mimicking the water transport behavior of Shorebird's beaks). This method helped large droplets quickly form and shed down easily. More than expected, the changes in fabric texture and fiber surface yielded an excellent result. The OBLWB-Warp@fabric's water harvesting rate was about 700% higher than that of the original plain weave fabric (Original@fabric). OBLWB-Warp@fabric's water harvesting rate was about 160% higher than that of Original–Warp@fabric. This shows the great practical application potential of woven fabrics with a low cost and large scale, or you can make use of textile wastes to collect fog, suitable for the current circular economy model. This study hopes to further enrich the materials used for fog harvesting. [ABSTRACT FROM AUTHOR]

In the last decade, the task of developing environmentally friendly and cost-effective methods for obtaining stable superhydrophobic coatings has become topical. In this study, we examined the effect of the concentrations of filler and polymer binder on the hydrophobic properties and surface roughness of composite coatings made from organic–aqueous compositions based on hexyl methacrylate (HMA) and glycidyl methacrylate (GMA) copolymers. Silicon dioxide nanoparticles were used as a filler. A single-stage "all-in-one" aerosol application method was used to form the coatings without additional intermediate steps for attaching the adhesive layer or texturing the substrate surface, as well as pre-modification of the surface of filler nanoparticles. As the ratio of the mass fraction of polymer binder (Wn) to filler (Wp) increases, the coatings show the lowest roll-off angles among the whole range of samples studied. Coatings with an optimal mass fraction ratio (Wn/Wp = 1.2 ÷ 1.6) of the filler to polymer binder maintained superhydrophobic properties for 24 h in contact with a drop of water in a chamber saturated with water vapor and exhibited roll-off angles of 6.1° ± 1°. [ABSTRACT FROM AUTHOR]

High-precision lunar scene 3D data are essential for lunar exploration and the construction of scientific research stations. Currently, most existing data from orbital imagery offers resolutions up to 0.5–2 m, which is inadequate for tasks requiring centimeter-level precision. To overcome this, our research focuses on using in situ stereo vision systems for finer 3D reconstructions directly from the lunar surface. However, the scarcity and homogeneity of available lunar surface stereo datasets, combined with the Moon's unique conditions—such as variable lighting from low albedo, sparse surface textures, and extensive shadow occlusions—pose significant challenges to the effectiveness of traditional stereo matching techniques. To address the dataset gap, we propose a method using Unreal Engine 4 (UE4) for high-fidelity physical simulation of lunar surface scenes, generating high-resolution images under realistic and challenging conditions. Additionally, we propose an optimized cost calculation method based on Census transform and color intensity fusion, along with a multi-level super-pixel disparity optimization, to improve matching accuracy under harsh lunar conditions. Experimental results demonstrate that the proposed method exhibits exceptional robustness and accuracy in our soon-to-be-released multi-scene lunar dataset, effectively addressing issues related to special lighting conditions, weak textures, and shadow occlusion, ultimately enhancing disparity estimation accuracy. [ABSTRACT FROM AUTHOR]

To address the inaccurate classification of coarse aggregate particle size due to insufficient height information in single‐view, a multi‐view and graph convolutional network (GCN) based method for coarse aggregate particle size classification was proposed in this study. First, the viewpoint selection and projection strategies were designed to build the aggregate multi‐view datasets. Then, the surface texture of the aggregate was reconstructed by using 3D point cloud information. Finally, self‐attention mechanism and three‐layer GCN were introduced to aggregate global shape feature descriptors. The experimental results show that the proposed interleaved self‐attention and view GCN model achieves a coarse aggregate particle size classification accuracy of 94.11%, outperforming other multi‐view classification algorithms. This method provides a new possibility for the accurate detection of aggregate particle size and provides significant support for the production and automatic detection of aggregate raw materials. [ABSTRACT FROM AUTHOR]

This study explored cefuroxime sodium (CXM) adsorption on sepiolite-rich dolomite, assessing the impact of various conditions like pH, contact time, temperature, and initial CXM concentration. The research utilized data mining, kinetic and isotherm models, and analytical techniques such as FTIR, SEM, and EDX to understand the adsorption mechanism and behavior. Findings indicated that pH significantly influenced CXM adsorption, with the highest efficiency at pH 5. Additionally, the adsorption kinetics were consistent with a pseudo-first-order model, showing that adsorption was rapid and cooperative and reached equilibrium within 60 minutes, while the Freundlich isotherm model best described the adsorption isotherm. The adsorption mechanism was mainly governed by the electrostatic attraction, ion exchange, and pore-filling processes, influenced by the adsorbent's surface heterogeneity and texture characteristics, the adsorbate functional groups, and the bulk solution. Thermodynamic parameters revealed the adsorption to be spontaneous, exothermic, and entropy-driven, suggesting a predominantly physical process. While the presence of negative ΔG values showed that adsorption preferred low temperatures, the presence of a positive ΔS value showed increased randomness at the solid-liquid interface during adsorption. SEM and FTIR results confirmed the changes in the sepiolite-rich dolomite's surface properties and functional groups after CXM adsorption. EDX analysis revealed that CXM's adsorption involved the replacement of Ca2+ ions by CXM's functional groups. The study proved that sepiolite-rich dolomite can be a very effective and environmentally friendly adsorbent to remove CXM and treat bacterial infections from domestic waste or wastewater. [ABSTRACT FROM AUTHOR]

An important aspect to consider in the evaluation of parts and assemblies by X-ray computed tomography (XCT) is the attenuation coefficient of the different materials involved, which are directly related to their density; depending on this coefficient, the X-ray penetration varies and, therefore, varies the contrast between different materials and with the background. This becomes more critical in those assemblies in which materials are characterized by a high difference in density, where the lighter material could be difficult to be characterised. In this paper, the effect of the presence of metals in the dimensional evaluation of polymeric geometries (having lower density than the metal parts) is studied, to evaluate the errors caused in dimensional measurements of different geometries and surface texture characterization. Based on a common geometry, four scenarios have been experimentally tested with variations of metal amount, in which macro geometries (precision spheres made by different polymers) and micro geometries (inclined ramps manufactured by fused deposition modelling (FDM)) have been characterised. Results show errors in the surface determination of the polymeric features directly related to the presence of metal: a high amount of steel makes significantly difficult to accurately determine the interface between background and material due to the noise and artifacts created, while aluminium has less influence on the irregularities of the features extracted. This effect is more evident for polymers with lower density due to the higher difference. Numerically, most affected parameters are those sensible to variations in surface determination, such as spheres' form error and ramps' maximum surface texture (Sz), while more solid features as spheres' diameters, distances and ramps' average surface texture (Sa and Sq) remain more stable. In conclusion and to sum up, it has been found that the quantity of metal present in assemblies made of polymeric and metallic materials is correlated with distortions in the dimensional evaluation of polymeric features by XCT. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to study the correlation between the thicknesses of the C–Ni films that have been prepared by RF-magnetron sputtering on quartz substrates and their three-dimensional (3D) micro morphology. In this work by AFM images, this paper studied stereo metric analysis of these films. Design/methodology/approach: The C–Ni films have been prepared by RF-magnetron sputtering on quartz substrates using a mosaic target consisting of pure graphite and strips of pure nickel approximately 2 cm2 attached to the graphite race track. The field emission scanning electronic microscopy (FESEM) images were used for the morphological characterization. Findings: The histogram peaks are zero for all samples and the histograms are almost symmetric around zero. Temperature did not have much effect on the degree of isolation, so all four diagrams have similar results. The qualitative observations through statistical parameters of the 3D surface texture revealed that the smoothest surface has been obtained for C-Ni films annealed at 500 °C (Sa, Sq, Sz and Sv have the lower values), while the most irregular topography has been found for C-Ni films annealed at 300 °C (the fractal dimension D = 2.01 ± 0.131). Originality/value: As shown in FESEM images, the size of the particles was increased for films deposited from 300 ºC to 800ºC; however, at 1000ºC, it decreased significantly. The histogram peaks are zero for all samples and the histograms were almost symmetric around zero. Also, the largest and lowest root mean heights (Sq) belong to films at 300 °C and 500 °C. Furthermore, the more irregular surface was found at 300 °C, and the more regular surface was found at 500 °C. As the temperature was increased to 800 °C, the values of the IAPSD function increased systematically, and then the values of the IAPSD function was decreased in the fourth sample. The surface skewness of samples annealed at 1000 °C was positive which confirms the lack of dominance of cavities on their surface with the highest amount of C-Ni films at 800 °C. [ABSTRACT FROM AUTHOR]

Introduction: This study explores potential application of silver nanoparticles (AgNPs) to treat periodontal infection using Azadirachta indica leaf extract. The eco-friendly green synthesis process uses Azadirachta indica as a natural stabilizer and reducer, allowing AgNPs to be formed. Methods: Experimental AgNPs were characterized through transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), Zeta potential, ultraviolet-visible spectroscopy (UV-Vis) etc. The antimicrobial, antioxidant potential of AgNPs was tested to identify its efficacy against periodontal infections. Results and discussion: AgNPs were found spherical, nanosized (86 nm), with negative surface charge (−26.9 mV). TEM study depicted clear formation of discrete nanosize particles with smooth surface texture. Results showed strong antibacterial and anti-oxidant action of experimental AgNPs, preventing biofilm growth and bacterial viability. A higher binding affinity was observed between Quercetin and the selected protein, which is implicated in bacterial growth and biofilm formation on teeth. The study suggests that Azadirachta indica derived AgNPs could be a safe, efficacious, and eco-friendly alternative in place of conventional therapies to treat periodontal infection. Future in vivo studies are however warranted. [ABSTRACT FROM AUTHOR]

Tactile sensors have garnered considerable interest for their capacity to detect and quantify tactile information. The incorporation of microstructural designs into flexible tactile sensors has emerged as a potent strategy to augment their sensitivity to pressure variations, thereby enhancing their linearity, response spectrum, and mechanical robustness. This review underscores the imperative for progress in microstructured flexible tactile sensors. Subsequently, the discourse transitions to the prevalent materials employed in the fabrication of sensor electrodes, encapsulation layers, and active sensing mediums, elucidating their merits and limitations. In‐depth discussions are devoted to tactile sensors adorned with microstructures, including but not limited to, micropyramids, microhemispheres, micropillars, microporous configurations, microcracks, topological interconnections, multilevel constructs, random roughness, biomimetic microstructures inspired by flora and fauna, accompanied by exemplar studies from each category. Moreover, the utility of flexible tactile sensors within the realm of intelligent environments is explicated, highlighting their application in the monitoring of physiological signals, the detection of sliding motions, and the discernment of surface textures. The review culminates in a critical examination of the paramount challenges and predicaments that must be surmounted to further the development and enhance the functional performance of tactile sensors, paving the way for their integration into advanced sensory systems. [ABSTRACT FROM AUTHOR]

The water as a welding environment may generate serious technological and metallurgical problems but in certain cases, the physicochemical properties of water can be used effectively, e.g., to impart the specific properties of welded materials. The purpose of the work was verification of effectiveness of the water cooling of aluminium alloy AA5754 for various sets of technological parameters of underwater friction stir welding (UFSW). For the joints performed with the range of parameters of rotational speed: 475–925 rpm and welding speed: 47.5–95 mm/min, the following examinations were carried out: visual tests, radiographic tests, static tensile test, fractography (SEM, scanning electron microscope) analysis, and surface texture analysis performed with 3D measurement system. All of the joints were characterized with some amount of flash. Besides, depending on the values of selected parameters, the defects arising from inadequate stirring were found—tunnel defects and melting. The best appearance of the joint was obtained for the set of parameters of 925 rpm and 47.5 mm/min. The samples of the same joint were found to be of the highest mechanical properties—ultimate tensile strength (UTS) of 194 MPa and elongation (A) of 9.2%. The results were confirmed by the fractography analysis, which in this case indicated the ductile fracture mode. Dynamic plastic behaviour strongly depends on the process parameter values, which was reflected in the results of surface texture analysis. The parameter selection resulted in significant changes in the roughness results (from 8 to 14.2 µm depending on the sample) as well as the flow ring distance of the weld (from 20 to 50 µm depending on the sample). [ABSTRACT FROM AUTHOR]

As a sooner or later risk, antimicrobial resistance due to the overuse of antibiotics is considered a nightmare facing humankind. The visible-light mineralization of antibiotic waste over nanoceramic photocatalysts is an innovative expectant method. Concerning this, nanostructured yttrium orthovanadate (YVO 4) is grown via an adapted sol-gel process tracked by loading of 1.0–4.0 wt% of silver oxide (Ag 2 O) to form heterojunction nanocomposite of Ag 2 O/YVO 4. The as-prepared heterostructures were applied for visible-light photoelimination of ciprofloxacin (CF) in water. The presence of Ag 2 O has enhanced both light absorbance and photogenerated carrier separation of YVO 4. The 3.0 to 4.0 wt% loading of Ag 2 O designated the thinnest bandgap of 2.4 eV regardless of the minor decrease in their specific surface areas from 220 in bare YVO 4 to 168 m2 g−1 for 3.0 % Ag 2 O/YVO 4. The complete mineralization of CF over 3.0 % Ag 2 O/YVO 4 was achieved after 60 min of light illumination at an optimized dose of 1.6 mg mL−1 and a reaction rate constant of 5.41 × 10−2 min−1. This improved photocatalyst has also a recyclable ability of ∼95 % of its initial photoactivity after the fifth experimental run. Therefore, the augmented light harvesting, surface texture, as well as superb carrier separation represent a key role in the performance of Ag 2 O/YVO 4. [ABSTRACT FROM AUTHOR]

Flexible robotic systems (FRSs) and wearable user interfaces (WUIs) have been widely used in medical fields, offering lower infection risk and shorter recovery, and supporting amiable human–machine interactions (HMIs). Recently, soft electric, thermal, magnetic, and fluidic actuators with enhanced safety and compliance have innovatively boosted the use of FRSs and WUIs across many sectors. Among them, soft hydraulic actuators offer great speed, low noise, and high force density. However, they currently require bulky electric motors/pumps, pistons, valves, rigid accessories, and complex controllers, which inherently result in high cost, low adaptation, and complex setups. This paper introduces a novel soft fibrous syringe architecture (SFSA) consisting of two or more hydraulically connected soft artificial muscles that enable electricity‐free actuation, motorless control, and built‐in sensing ability for use in FRSs and WUIs. Its capabilities are experimentally demonstrated with various robotic applications including teleoperated flexible catheters, cable‐driven continuum robotic arms, and WUIs. In addition, its sensing abilities to detect passive and active touch, surface texture, and object stiffness are also proven. These excellent results demonstrate a high feasibility of using a current‐free and motor‐less control approach for the FRSs and WUIs, enabling new methods of sensing and actuation across the robotic field. [ABSTRACT FROM AUTHOR]

The cavitation phenomenon presents a significant challenge in pump operation since the losses incurred by cavitation adversely impact pump performance. The many constraints of conventional anti-cavitation techniques have compelled researchers to explore biological processes for innovative alternatives. Consequently, the use of bionanotechnology for anti-cavitation pumping has emerged as a prominent study domain. Despite the extensive publication of publications on biomimetic technology, research concerning the use of anti-cavitation in pumps remains scarce. This review comprehensively summarizes, for the first time, the advancements and applications of bionic structures, bionic surface texture design, and bionic materials in pump anti-cavitation, addressing critical aspects such as blade leading-edge bionic structures, bionic worm shells, microscopic bionic textures, and innovative bionic coatings. Bionic technology may significantly reduce cavitation erosion and improve pump performance by emulating natural biological structures. This research elucidates the creative contributions of biomimetic designs and their anti-cavitation effects, hence boosting the anti-cavitation performance of pumps. This work integrates practical requirements and anticipates future applications of bionic technology in pump anti-cavitation, offering a significant research direction and reference for scholars in this domain. [ABSTRACT FROM AUTHOR]

Measurements of areal (3D) surface texture using optical methods are very popular because of the short measurement time compared to the stylus tip technique. However, they are very sensitive to measurement errors. In some cases, optical measurements are not recommended. The stylus measurement method is well known and can be the reference technique for surface texture measurement. The main disadvantage is the long measuring time. This time can be shortened using higher speeds of measurement. The effect of the speed of the measurement of stylus profilometer on changes in surface texture parameters was studied. Fifty surface topographies were measured using the stylus profilometer at speeds 0.5, 1, 2, 3, 4, and 5 mm/s in the same places. Surfaces after lapping, polishing, grinding, milling, laser texturing, and two-process random surfaces were measured and analyzed. Changes in parameters caused by the increase in the traverse speed depend on the characteristics and parameters of the surfaces. The random surfaces changed more than the deterministic ones. The increase in the traverse speed from 0.5 to 1 mm/s caused small changes in the parameters. [ABSTRACT FROM AUTHOR]

Magnesium and its alloys, valued for their lightweight and durable characteristics, have garnered increasing attention for biomedical applications due to their exceptional biocompatibility and biodegradability. This work introduces a comparison of advanced and basic methods—laser texturing and sandblasting—on magnesium surfaces to enhance bioactivity for biomedical applications. Employing a comprehensive analysis spanning surface morphology, hardness, wettability, tribological performance, and corrosion behavior, this study elucidates the intricate relationship between varied surface treatments and magnesium's performance. Findings reveal that both laser texturing and sandblasting induce grain refinement. Notably, sandblasting, particularly with a duration of 2 s, demonstrates superior wear resistance and reduced corrosion rates compared to untreated magnesium, thereby emerging as a promising approach for enhancing magnesium bioactivity in biomedical contexts. This investigation contributes to a deeper understanding of the nuanced interactions between diverse surface treatments and their implications for magnesium implants in chloride-rich environments, offering valuable insights for prospective biomedical applications. [ABSTRACT FROM AUTHOR]

To make supercapacitors a viable commercial product, it is necessary to increase the mass loading (ML) of the electrodes. However, current research on high ML MXene electrodes mainly focuses on internal structure optimization, often neglecting the importance of surface texture in the electrodes, which plays a crucial role in mediating interactions between the internal structure and the electrolyte. This study reports on a simple ion‐intercalation process that can reduce charge transfer resistance and improve cycling stability. Through the integration of 3D visualization models and wide‐angle X‐ray scattering techniques, a comprehensive investigation of the electrode's surface structure and MXene flake arrangement is conducted. The results showed that pre‐oriented aggregates induced by ion‐intercalation create a sophisticated surface structure with rich hills and valleys, promoting electrolyte permeation and ion exchange. This work highlights the significance of surface texture in films and electrodes, guiding the design of high‐performance materials. [ABSTRACT FROM AUTHOR]

Biodegradable metals have become a new generation of materials for orthopedic and cardiovascular implantable devices due to their good degradability and biocompatibility. Precise bioadaptability principle requires the degradation behavior to be accurately adapted to the tissue repair in both time and space dimensions. However, most approaches deal with degradation control from a global perspective for a whole implant and neglect local precision control and directional control of degradation. In this paper, ultrafast pulsed laser surface modification method was used to tailor the degradation behavior of biodegradable zinc metal. Different micro/nanostructures including undulating grooves, streak and columns were obtained after nanosecond laser and femtosecond laser texturing. The former exhibited higher roughness values than the latter, and all laser texturing surfaces presented better hydrophobicity compared with the polished one. Electrochemical and immersion tests showed that the corrosion rate of zinc metal after laser modification was significantly elevated due to the synergistic effects of surface roughness and oxidation. Based on the above, the pure zinc metal rod with different laser surface texturing regions along the axial direction was designed, and its degradation was driven toward specific direction in SBF solution as expected. Results of this research can provide a new approach to tailor the degradation of biodegradable metals precisely. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Three-dimensional (3D) printed temporal bone model draws great attention as a promising alternative for conventional cadaveric model in education of otologic surgery. However, its high price and requirement for specialized tools hinder widespread use. We devised a simple educational model based on lattice structure to overcome these problems and compared it with a commercial model. METHODS: We converted high-resolution temporal bone computed tomography images into stereolithography format, and printed it using the G005 3D printing system from CUBICON©. In this process, the part to be drilled out was made of lattice structure. We evaluated the model by a questionnaire prepared in advance, and compared the results with those of a commercial model. RESULTS: We created an educational 3D printed temporal bone lattice model one-tenth the cost of commercial temporal bone. Our model reproduced the important structures of the temporal bone, produced less dust, and had similar strength and grinding sensation compared to the commercial model. The surface texture and reproducibility were comparable to the commercial model. Although most of structures were remodeled more elaborately in the commercial model than our model, our model demonstrated significant potential as a cost-effective educational tool for medical students and residents. CONCLUSION: 3D printed temporal bone lattice model has potential for widespread use due to low cost and easy accessibility. Further improvements in the fine structures of the temporal bone are necessary to enhance its utility as an educational model. [ABSTRACT FROM AUTHOR]

This study presents a pioneering methodology for the synthesis of aluminum matrix composites (AMCs) fortified with biochar, sourced from renewable biomass feedstocks. Employing a systematic approach, various biochar weight percentages were meticulously investigated to discern their impact on the mechanical and tribological properties of the resulting composites. Through a comprehensive battery of tests, encompassing evaluations of compressive strength and hardness, the study elucidated significant enhancements in mechanical robustness consequent to biochar integration. Notably, the mixture formulation with 7.5 wt. % biochar emerged as the optimal configuration, showcasing an impressive 8.83% augmentation in compressive strength and a notable 15% elevation in the hardness relative to the pristine aluminum pure matrix. The research extends beyond traditional analyses, introducing an exploration of tribological performance. The incorporation of biochar is anticipated to impart solid lubricating properties, influencing wear and friction characteristics. Future research directions may delve into the nuanced interplay between biochar content and tribological enhancements, offering insights into the tailored manipulation of mechanical and tribological properties in AMC through biochar reinforcement. The examination of wear and friction exhibited that the friction coefficient decreased by 6.4% when 10 wt. % of biochar was added. Furthermore, the wear resistance improved proportionally with the biochar weight percentage, regardless of the normal loads applied. The finite element model further demonstrated an enhancement in load-carrying capacity due to biochar incorporation. Finally, analysis of the texture of the rubbed surface presented that the inclusion of biochar in an AL matrix changed the way wear occurs and decreased the amount of weight lost during friction. The resulting materials not only exhibit improved mechanical strength but also hold promise for applications in industries that demand robust, environmentally conscious solutions with enhanced tribological performance. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to enhance lubrication performance of the pitcher plant–like textured surface with various parameters. Design/methodology/approach: A pitcher plant–like structure surface is fabricated on the copper alloy, and the lubrication performance of the pitcher plant–like structure with various parameters is evaluated. In addition, the pressure distribution and oil film load capacity of the pitcher plant–like surface are simulated based on Navier–Stokes equations. Findings: When the direction of motion aligns with the pitcher plant–like structure, the friction coefficient remains lower than that of the nontextured surface, and it exhibits a decreasing trend with the increasing of the texture width and spacing distance; the lowest friction coefficient (0.04) is achieved with B = 0.3 mm, L = 1.0 mm and θ = 45°, marking a 75% reduction compared to the nontextured surface. Simulation results demonstrate that with the increase in texture width and spacing distance, the oil film load-bearing capacity demonstrates an increasing trend. Originality/value: Bionic pitcher plants are prepared on the copper alloy to improve the lubrication performance and wear resistance. Peer review: The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2024-0119/ [ABSTRACT FROM AUTHOR]

Purpose: This study aims to evaluate the interactions of fluoride-containing gels and varnishes on the optical properties and surface texture of composite resins, compomers, and bulk-fill composite resins. Thus, it seeks to address the current gap in the literature regarding the effect of fluoride agents on bulk-fill restorative materials. Methods: Using Teflon moulds, 50 specimens of 6 mm diameter and 2 mm thickness were produced for each of the G-ænial Posterior, Filtek™ One Bulk-Fill and Dyract-XP materials. Baseline color and surface roughnesss measurements of the specimens were performed. The specimens were subjected to the following applications: Study groups (Topex NaF gel, Topex APF gel, ProShield varnish, and MI varnish with RECALDENTTM) and Control group (distilled water). Color and surface roughness measurements were repeated after the application period. The surface microhardness of the specimens (study groups and control group) was measured using Vickers microhardness tester. Statistical analyses, including two-way analyses of variance (comparison of color, whiteness and microhardness parameters) and three-way analyses of variance (comparison of surface roughness parameter), and Pearson's correlation test (the relationship between surface roughness and color change and surface roughness), were applied. Results: The restorative material significantly (p-value<0.001) influenced the color changes (ΔE00), with the Filtek™ One Bulk-Fill/Topex APF gel interaction yielding the highest ΔE00 average value (2.1±1.15). Materials and fluoride agents exerted significant effects on the Whiteness Index (ΔWID) for Dentistry (pvalue< 0.001). Dyract-XP displayed lower initial surface roughness (1.05±1.38), with all materials exhibiting comparable values after fluoride treatment. Microhardness varied among the materials, with Filtek™ One Bulk-Fill having the highest total value (65.39±2.67) and G-ænial Posterior having the lowest total (42.97±3.32) value. When considering the interaction of restorative materials, fluoride treatment, Topex APF gel-treated G-ænial Posterior showed the lowest (40.56±1.78) microhardness, whereas Filtek™ One Bulk-Fill showed the highest (65.06±1.88) values. Conclusions: Topical fluoride agents induce alterations in the color, roughness, and hardness of restorative materials, depending on the material type, fluoride agent, and duration of application. [ABSTRACT FROM AUTHOR]

This paper investigates the significant factors influencing the measurement uncertainty of 3D laser scanners, an essential tool in industrial contexts for swiftly and accurately analysing complex geometric objects. Through a designed experimental study, parameters such as object size, surface texture, scanner resolution, and ambient light intensity were systematically varied to assess their impact. The results demonstrate that nominal shaft diameter, ambient light intensity, surface finish of the shaft, scan resolution, and the interaction between surface finish and resolution significantly affect repeatability. An empirical model was developed to predict repeatability in shaft diameter measurements. Additionally, the exploration of developer coating revealed its pivotal role in minimising errors stemming from reflective surfaces, underscoring its importance in ensuring measurement reliability. The main contribution of the paper belongs to the knowledge and practice of 3D laser scanning by offering practical recommendations and guidelines. [ABSTRACT FROM AUTHOR]

The increasing demand for accurate and detailed 3D modeling in fields such as cultural heritage preservation, industrial inspection, and scientific research necessitates advanced techniques to enhance model quality. This paper addresses this necessity by incorporating spectral imaging data to improve the surface detail and reflectivity of 3D models. The methodology integrates spectral imaging with traditional 3D modeling processes, offering a novel approach to capturing fine textures and subtle surface variations. The experimental results of this paper underscore the advantages of incorporating spectral imaging data in the creation of 3D models, particularly in terms of enhancing surface detail and reflectivity. The achieved experimental results demonstrate that 3D models generated with spectral imaging data exhibit significant improvements in surface detail and accuracy, particularly for objects with intricate surface patterns. These findings highlight the potential of spectral imaging in enhancing 3D model quality. This approach offers significant advancements in 3D modeling, contributing to more precise and reliable representations of complex surfaces. [ABSTRACT FROM AUTHOR]

Defect detection on steel surfaces with complex textures is a critical and challenging task in the industry. The limited number of defect samples and the complexity of the annotation process pose significant challenges. Moreover, performing defect segmentation based on accurate identification further increases the task's difficulty. To address this issue, we propose VQGNet, an unsupervised algorithm that can precisely recognize and segment defects simultaneously. A feature fusion method based on aggregated attention and a classification-aided module is proposed to segment defects by integrating different features in the original images and the anomaly maps, which direct the attention to the anomalous information instead of the irregular complex texture. The anomaly maps are generated more confidently using strategies for multi-scale feature fusion and neighbor feature aggregation. Moreover, an anomaly generation method suitable for grayscale images is introduced to facilitate the model's learning on the anomalous samples. The refined anomaly maps and fused features are both input into the classification-aided module for the final classification and segmentation. VQGNet achieves state-of-the-art (SOTA) performance on the industrial steel dataset, with an I-AUROC of 99.6%, I-F1 of 98.8%, P-AUROC of 97.0%, and P-F1 of 80.3%. Additionally, ViT-Query demonstrates robust generalization capabilities in generating anomaly maps based on the Kolektor Surface-Defect Dataset 2. [ABSTRACT FROM AUTHOR]

This article explores the properties of composite materials employed in dental fillings. A traditional nano-hybrid composite containing nanofiller particles exceeding 82% by weight served as a benchmark. The remaining samples were fabricated from ormocer resin, maintaining an identical nanofiller content of 84%. In all specimens, the nanoparticles were dispersed randomly within the matrix. This study presents findings from investigations into surface geometry, hardness, wettability, and tribological behavior. The microscopic observations revealed that ormocer-based samples exhibited greater surface roughness than those composed of the traditional composite. Hardness testing indicated that both ceramic addition and sample preparation significantly influenced mechanical properties. Ceramic-enhanced samples demonstrated superior hardness, surpassing the reference composite by 30% and 43%, respectively. Contact angle measurements revealed hydrophilic characteristics in the classic composite, contrasting with the hydrophobic nature of ceramic-containing samples. Tribological evaluations revealed the superiority of the classic composite in terms of friction coefficients and volumetric wear compared to ormocer-based materials. [ABSTRACT FROM AUTHOR]

LSPwC is an important development of Laser shock peening (LSP) technology, and surface texturing is an effective method to improve tribological properties. The combination of these is expected to innovate a new surface texturing technology with a strengthing effect, but no one has attempted it. In this paper, a new LSPTwC technology combining them is innovatively proposed and validated on AISI 9310 steel, which is commonly used in helicopter transmission components for surface texturing. The LSPTwC surface was studied using an optical microscope, electron microscope, energy dispersive spectrometer, and so on. The results proved that LSPTwC is an effective texturing method of AISI 9310 steel, which modulates the texture and improves the properties, such as the microhardness increased by more than 10%. A model for calculating the texture and process parameters is also constructed on a statistical basis, and a modeling method for textured surfaces is proposed. It is verified that the calculation results and the constructed model are highly consistent with the test, with a diameter deviation <3% and depth deviation <4%. The above results can provide the experimental basis, process design method, and calculation model for single-point LSPwC texturing of AISI 9310 steel parts for helicopters, which have application value. [ABSTRACT FROM AUTHOR]

The colonization of microbes and the resulting formation of biofilms on dental implants are significant contributors to peri-implantitis and the failure of these implants. The aim of the research was to analyze the impact of density and depth of laser texturing of the Ti-6Al-7Nb alloy surface on the colonization of selected microorganisms and biofilm formation. Standard strains of Gram-negative and Gram-positive bacteria and yeasts from the American Type Culture Collection—ATCC—were used to demonstrate the ability to form single-species biofilms in vitro. The study evaluated three types of titanium samples with different texture density and depth. The colonization and biofilm formation abilities of the tested microorganisms were assessed. The obtained results were subjected to statistical analysis. Among the analyzed strains, L. rhamnosus showed the highest colonization of the tested surfaces. It was found that there is no relationship between the texture parameters and the number of colony-forming units (CFU/mL) for C. albicans, S. mutans, and L. rhamnosus. For the F. nucleatum strain, it was shown that the number of colony-forming bacteria is related to the texture density. [ABSTRACT FROM AUTHOR]

As sand moves across Earth's landscapes, the shapes of individual grains evolve, and microscopic textures accumulate on their surfaces. Because transport processes vary between environments, the shape and suite of microtextures etched on sand grains provide insights into their transport histories. For example, previous efforts to link microtextures to transport environments have demonstrated that they can provide important information about the depositional environments of rocks with few other indicators. However, such analyses rely on 1) subjective human description of microtextures, which can yield biased, error-prone results; 2) nonstandard lists of microtextures; and 3) relatively large sample sizes (>20 grains) to obtain reliable results, the manual documentation of which is extremely labor intensive. These drawbacks have hindered broad adoption of the technique. We address these limitations by developing a deep neural network model, SandAI, that classifies scanning electron microscope images of modern sand grains by transport environment with high accuracy. The SandAI model was developed using images of sand grains from modern environments around the globe. Training data encompass the four most common terrestrial environments: fluvial, eolian, glacial, and beach. We validate the model on quartz grains from modern sites unknown to it, and Jurassic-Pliocene sandstones of known depositional environments. Next, the model is applied to two samples of the Cryogenian Bråvika Member (of contested origin), yielding insights into periglacial systems associated with Snowball Earth. Our results demonstrate the robustness and versatility of the model in quickly and automatically constraining the transport histories recorded in individual grains of quartz sand. [ABSTRACT FROM AUTHOR]

CoCrMo alloys are often used in the manufacture of artificial joints in the medical field, and their special working environment will lead to corrosion and abrasion of the surface materials, thus reducing the service life of the joints. Surface texturing technology can improve the friction performance of joints by reducing the friction area, storing abrasive particles and lubricants, etc. Its application in the field of CoCrMo alloy joint surface strengthening is of great significance. This paper analyses the characteristics of surface fabrication processing technology and the friction reduction mechanism of surface fabrication under fluid lubrication and dry friction conditions, summarizes the influence of various fabrication parameters (fabrication depth, size, density, shape, etc.) on the friction performance of the alloy, introduces other surface technologies of CoCrMo alloy as well as common medical materials, summarizes the existing problems in the research of CoCrMo alloy surface reinforcement technology at this stage and makes a study on the development direction of the surface reinforcement technology of CoCrMo alloy in the field of artificial joints. The development direction of CoCrMo alloy in the field of artificial joints is also prospected. [ABSTRACT FROM AUTHOR]

In this study, the fruit and seed morphology of all the Periplocoideae (Periploca gracilis and P. graeca) and the majority of Asclepiadoideae (Araujia sericifera, Cionura erecta, Cynanchum acutum and Gomphocarpus fruticosus) taxa in Türkiye was evaluated from a taxonomic point of view using, for the first time, both light and scanning electron microscopy. Macro- and micro-morphological investigations were carried out on herbarium samples. An identification key for the examined Periplocoideae and Asclepiadoideae taxa, and expanded fruit and seed descriptions for each taxon were prepared. Numerical analysis showed that shape and size of follicle, size, shape and surface texture of seed were found to be effective in delimiting the studied Periplocoideae and Asclepiadoideae taxa at subfamilial and generic levels. [ABSTRACT FROM AUTHOR]

Polymers are versatile materials widely used in various industries, with significant applications in biomedicine where biofouling on polymer surfaces presents major health and economic challenges. Biofouling, initiated by bacterial adhesion, can be mitigated by modifying surface properties through laser micro- and nano-texturing, an approach that offers advantages over chemical treatments. This study introduces an economical mass production process for textured polymeric components using injection molding to replicate hierarchical textures. Testing revealed that all textured samples significantly reduced bacterial adhesion compared to untextured surfaces across different designs and bacteria types after 24 h of culture. The study examined factors like wettability, nanoscale roughness, and pattern dimensions to explain these outcomes, comparing them with existing studies. Despite all textured samples showing decreased wettability and roughness, these factors alone did not ensure reduced bacterial adhesion. The most effective anti-adhesive performance was observed in surfaces with parallel ridge patterns, which segmented the surface into isolated areas that limited bacterial interaction and hindered micro-colony formation, highlighting the importance of specific surface patterning in combating biofouling. [ABSTRACT FROM AUTHOR]

This research paper presents an innovative approach to fabricating enhanced-quality hierarchical surface micro-textures on Ti6Al4V alloy by synergistically employing in situ electrical discharge machining (EDM) and electrochemical machining (ECM) processes. The hierarchical structure encompasses three levels: a primary level at a few hundred micrometers, a secondary level at a few tens of micrometers, and a ternary level at sub-micrometer scales. Despite the precision achieved in generating the primary-level texture through EDM using a chemically patterned tool, inherent thermal damages and surface defects, such as micro-craters and irregularities, pose challenges. Unlike usual ex situ chemical or electrochemical post-processing methods, this study introduces in situ ECM post-processing (ECM) with the same patterned tool. This approach enhances the quality of EDMed surfaces without compromising geometrical accuracy, offering anisotropic dissolution along the feature depth. To ensure geometrical accuracy, an experimentally validated finite element method-based transient numerical simulation model is developed. This model accurately predicts the evolution of the feature profile during the ECM operation. Furthermore, ECM with a fluoride ion–containing electrolyte introduces additional secondary and ternary levels of hierarchical textures. Fluoride ions play a pivotal role in augmenting material removal during ECM, particularly in areas around micro-crevices and pores, shaping the secondary-level texture. [ABSTRACT FROM AUTHOR]

This paper presents a numerical study on the investigation of microscopic mechanism governing the interaction of woven geotextile and angular sand employing the 3D discrete element method (DEM). The surface texture and tensile properties of the geotextile were simulated using overlapping spherical particles, and the angular sand was simulated using rigid blocks. The DEM models were fully calibrated based on previous experimental data. The shear and dilation zones of sand near the interface were quantitatively determined based on particle displacement gradients. Analysis of contact forces was conducted to explain the microscopic mechanism behind the macroscopic strength evolution. The influence of geotextile surface roughness on the shear strength of the geotextile-sand interface is also discussed. The results show that the failure mode of the woven geotextile-sand interface is a combination of particle sliding failure along the geotextile surface and shear failure of the sand within the shear zone above the interface. There is a rapid redistribution of contact forces prior to reaching peak shear resistance, and the average normal contact force within the shear zone remains relatively constant after the peak shear stress is achieved. A completely developed shear zone stabilizes soil deformation, typically after achieving the peak shear resistance. • The thickness of the stabilized shear zone decreases as the normal stresses increase. • The shear zone is completely developed after the peak shear resistance is reached. • Contact forces are rapidly redistributed prior to reaching peak shear resistance. • The evolution of shear strength is caused by interparticle sliding in the shear zone. [ABSTRACT FROM AUTHOR]

The amount of attention paid to in-situ monitoring in Additive Manufacturing (AM) has significantly increased over the last few years, paving the way to a paradigm shift for quality monitoring and control via big data analysis of signals, images, and videos. In-situ quality monitoring represents an opportunity for waste reduction and first-time-right production via inline detection of process flaws, which allows early identification of scraps and the possibility of correcting actions for first-time-right production. This article presents a solution for in-situ monitoring of images taken layerwise in material extrusion AM. Compared with the existing solutions, mainly focusing on monitoring the shape deviation observed at each layer with respect to the nominal shape, this article focuses on monitoring the internal surface texture with the aim of detecting over- and under-extrusion flaws. Inspired by an approach reported in the literature that was developed for textile image monitoring, we propose a solution for in-situ monitoring of textured surfaces which is based on combining Random Forests with clustering to automatically identify defective locations layerwise. A real case study based on Fused Filament Fabrication is used to compare the performance of the novel proposed solution with the original one and identify an appropriate direction for future research. [ABSTRACT FROM AUTHOR]

Utilizing recycled concrete aggregate (RCA) is a countermeasure to address the scarcity of landfills and the depletion of natural aggregates. Surface modification techniques have been proposed and implemented to improve the properties of RCA; however, to our best knowledge, few investigations on improving RCA under various pozzolanic slurry concentrations and extended soaking durations have been done. This study comprehensively assessed the properties and microstructure of low-strength RCA treated with cement–fly ash slurry with different concentrations and soaking durations. The purposes of this study were not only to provide the optimal slurry concentration and treatment duration but also to explore the enhancement mechanism of RCA under various treatment conditions. The RCA from concrete with a low-strength grade of 20 MPa was soaked in cement–fly ash slurry at low and high concentrations (i.e., 30% and 70% by mass of RCA, respectively) for 24 and 72 h. The physical and mechanical properties of RCA before and after treatment were evaluated through water absorption and crushing value measurements, respectively. Additionally, the pore structure, Ca(OH)2 contents, surface morphology, and phase compositions of RCAs were evaluated through a mercury intrusion porosimetry test, thermal gravimetric differential thermal analysis (TG-DTA), scanning electron microscopy, and X-ray diffraction (XRD) analyses, respectively. The water absorption of treated RCA reduced by 9.2%–37.9%, whereas the crushing value decreased by 8.6%–26.9% compared with the untreated RCA. The TG-DTA results indicated a 22.3%–43.8% increase in the Ca(OH)2 content of treated RCA. The XRD analysis depicted a higher ettringite (AFt) peak in all treated RCA samples compared with the untreated sample. For both concentrations, with a 24 h treatment, the slurry infiltration effect was clearly observable, whereas the 72 h treatment resulted in the formation of a pozzolanic coating layer on the RCA surface. In conclusion, the optimal slurry concentration and soaking duration were 70% and 72 h, respectively. [ABSTRACT FROM AUTHOR]

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In order to improve the tribological properties of the 7075-T6 aluminum alloy used on the rotor surface, a combined method of cryogenic treatment and laser surface texture treatment was applied. Various tests, including metallographic microscopy, scanning electron microscopy, elemental analysis, microhardness measurements, were conducted to examine the wear morphology and modification mechanism of the treated 7075-T6 aluminum alloy surface. A numerical simulation model of surface texture was established using computational fluid dynamics to analyze the lubrication characteristics of V-shaped texture. The research finding that the 7075-T6 aluminum alloy experienced grain refinement during the cryogenic treatment process, enhancing the wear resistance of the V-shaped textures. This improvement delayed the progression of fatigue wear, abrasive wear, and oxidative wear, thereby reducing friction losses. The designed V-shaped texture contributes to reducing contact area, facilitating the capture and retention of abrasives, and enhancing oil film load-bearing capacity, thereby improving tribological performance. The synergistic effect of cryogenic treatment reduced the friction coefficient by 24.8% and the wear loss by 66.4%. Thus, the combination of surface texture and cryogenic treatment significantly improved the tribological properties of the 7075-T6 aluminum alloy. [ABSTRACT FROM AUTHOR]

Surface grinding is a widely employed finishing process in industrial sectors dedicated to achieve desired Surface characteristics of components. This study experimentally investigates the impact of the grinding parameters pertaining to the surface characteristics of Inconel 800, which is a nickel-iron-chromium alloy extensively used in high-temperature applications. Various commercially available grinding wheels were employed to grind Inconel800 under different grinding conditions. The ground surfaces were comprehensively analyzed using surface roughness measurements, Three-dimensional profilometry, optical microscopy, findings from XRD and SEM reveal that grinding parameters and wheel characteristics significantly impact the surface texture, topographical features, residual stress, and surface morphology of the machined nickel alloy.. The insights from this investigation contribute to the understanding of the grinding behavior of nickel-based superalloys and provide a basis for optimizing the grinding process for enhanced surface integrity. The findings are valuable for industries dealing with the machining of high-performance nickel alloy components. [ABSTRACT FROM AUTHOR]