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The experimental study of the angle-resolved hemispherical light scattering by V 4 O 7 film within a broad temperature range across metal–insulator transition reveals complex structural reorganization of the film deposited on the c-cut sapphire crystal. The bidirectional scattering distribution function and the surface autocorrelation function were obtained from scattering data to visualize statistics of the spatially resolved contributions of optical inhomogeneities in normal and lateral directions to the surface. The measurements reveal an anisotropic surface roughness distribution due to the twinned domain structure, with significant anisotropy changes across the phase transition. The V 4 O 7 film deposited on sapphire leads to a polydomain structure, minimizing elastic strain energy with distinct multiscale distributions of surface domains. Near T c , the material shows the lowest roughness but the highest lateral disorder of the surface. [ABSTRACT FROM AUTHOR]

Hafnium diboride (HfB2) is a promising candidate as a seed layer for GaN growth on Si substrates due to its excellent lattice and thermal coefficients matching with both materials. This work investigates the epitaxial growth of AlB2-type non-stoichiometric HfB2 (HfB2+δ with −0.1 < δ < 0.6) thin films on Si(111) using magnetron co-sputtering. We demonstrated that the process temperature significantly affected the surface roughness (RRMS ∼ 0.5–4 nm), film composition, and the nucleation of secondary impurity phases. Films deposited between 700 and 900 °C exhibit epitaxial growth on the Si substrate with a well-defined relationship of (0001) HfB 2 ‖ (111) Si and [ 11 2 ¯ 0 ] HfB 2 ‖ [ 1 1 ¯ 0 ] Si . Detailed x-ray diffraction and scanning transmission electron microscopy analyses reveal that impurity phases detected at high temperatures are primarily carbon-rich phases, identified as HfCx or HfCxBy. Interestingly, this secondary phase's crystal orientation follows the orientation of its surroundings. The different findings in terms of contamination (C and O) and deposition temperature offer valuable insights for further growth optimizing of high-quality epitaxial HfB2 thin films on Si(111) for future GaN-on-Si integration. [ABSTRACT FROM AUTHOR]

Purpose: To compare the color dimensions, color discrepancies (E00), and surface roughness of milled materials before and after application of a bleaching agent. Materials and Methods: A total of 10 extracted molars were obtained. Each tooth was cut in transverse sections to create disks (3-mm thick, 10-mm diameter; control group). Disk specimens of eight materials (n = 10 per group) were fabricated: polymethyl methacrylate (PMMA) interim material (PMMA-Telio group), two resin nanoceramics (RNC-Ultimate group and RNC-Cerasmart group), two hybrid ceramics (HC-Shofu group and HC-Enamic group), lithium disilicate (LD-Emax group), zirconia-reinforced glass ceramic (ZGC-Suprinity group), and zirconia (Zr-InCeram group). Color measurements were obtained using a spectrophotometer before and after applying 35% hydrogen peroxide-based bleaching agent. Pre- and postbleaching surface roughness (Sa) analyses were completed using a profilometer. Results: Significant L*, a*, b*, and E00 value differences were found (P < .05). Color discrepancies (E00) ranged from 0.30 ± 0.14 to 4.82 ± 0.10. The highest color discrepancies were measured on the PMMA-Telio group, while the lowest color discrepancies were computed for ZGC-Suprinity, RNCUltimate, and RNC-Cerasmart. Significant surface roughness differences were found (P < .05). The largest increase of surface roughness values between the pre- and postbleaching measurements was obtained in the PMMA-Telio group with a mean Sa value of 4.73 ± 3.02, while the largest decrease of surface roughness values between the pre- and postbleaching measurements was obtained in the Zr-InCeram group with a mean Sa value of -1.58 ± 0.10. Conclusions: The milled materials showed significant pre- and postbleaching color and surface roughness discrepancies. [ABSTRACT FROM AUTHOR]

Nonpolar (100), polar (002), semipolar (101), and nonpolar (110) preferred oriented ZnO films were synthesized by regulated growth using the chemical bath deposition method. The crystallinity, surface morphology, and optical properties of ZnO films with different preferred orientations after annealing in different atmospheres were systematically investigated. The experimental results show an increase in crystallinity and a decrease in surface roughness of the films after annealing; in particular, the optical transmittance of semipolar (101) preferred oriented ZnO films was significantly higher than that of the other samples. XPS and PL spectra confirmed that annealing in argon effectively increased donor defects, whereas annealing in oxygen and ozone reduced donor defects in the films, and that ozone annealing was best suited to enhance acceptor defects in nonpolar (110) preferred oriented ZnO films. Argon annealing is the best for the enhancement of donor defects in polar (002) preferred oriented ZnO films. This work achieves modulation of optical properties and defects of ZnO films by annealing in different atmospheres, which provides new ideas for the application of ZnO materials. [ABSTRACT FROM AUTHOR]

Recently, deep-ultraviolet (DUV) light-emitting devices have attracted attention for various applications. GaN/AlN superlattices have emerged as a promising alternative for achieving high-efficiency DUV emission. To fabricate superlattices with high crystal quality and abrupt interfaces, we have utilized face-to-face-annealed sputter-deposited AlN template substrates characterized by a flat surface and low dislocation density. Furthermore, radio-frequency plasma-assisted molecular beam epitaxy with in situ reflection high-energy electron diffraction monitoring was employed for the growth process. The growth of the superlattices follows a specific sequence. Step 1: AlN growth, Step 2: conversion of Al droplets to AlN, Step 3: GaN growth, and Step 4: evaporation of Ga droplets. This study explored the impact of GaN thickness on the GaN/AlN superlattice. The GaN thickness was linearly controlled by changing the duration of Step 3. This approach allowed for the growth of a flat GaN layer up to 1 monolayer (ML) and achieved superlattices with abrupt interfaces. Single-peak cathodoluminescence (CL) emission at 240–245 nm was observed from the superlattices, with the peak shift toward longer wavelengths as the GaN thickness increased. In contrast, quantum dot-like GaN islands were generated with a thickness of over 1 ML, induced by compressive strain. Superlattices with thicker GaN exhibited broad CL emission with multiple peaks. However, the AlN barrier layer reduced the surface roughness and maintained abrupt interfaces within the superlattices. Therefore, to obtain sharp single-peak UV emission from GaN/AlN superlattices, the growth sequence should be controlled to obtain flat GaN layers without dots. [ABSTRACT FROM AUTHOR]

Achieving high material perfection in aluminum (Al) films and their associated Al/AlOx heterostructures is essential for enhancing the coherence time in superconducting quantum circuits. We grew Al films with thicknesses ranging from 3 to 30 nanometers (nm) epitaxially on sapphire substrates using molecular beam epitaxy (MBE). An integral aspect of our work involved electron-beam (e-beam) evaporation to directly deposit aluminum oxide (Al2O3) films on the freshly grown ultrathin epitaxial Al films in an ultra-high-vacuum (UHV) environment. This in situ oxide deposition is critical for preventing the oxidation of parts of the Al films, avoiding the formation of undesired native oxides, and thereby preserving the nm-thick Al films in their pristine conditions. The thicknesses of our Al films in the study were accurately determined; for example, coherence lengths of 3.0 and 20.2 nm were measured in the nominal 3.0 and 20 nm thick Al films, respectively. These Al films were epitaxially grown on sapphire substrates, showing an orientational relationship, denoted as Al (111) ⟨ 2 1 ¯ 1 ¯ ⟩ ∥ sapphire (0001) [ 2 1 ¯ 1 ¯ 0 ]. The Al/sapphire interface was atomically ordered without any interfacial layers, as confirmed by in situ reflection high-energy electron diffraction (RHEED) and cross-sectional scanning transmission electron microscopy (STEM). All sample surfaces exhibited smoothness with a roughness in the range of 0.1–0.2 nm. The Al films are superconducting with critical temperatures ranging from 1.23 to around 2 K, depending on the film thickness. [ABSTRACT FROM AUTHOR]

In additive manufacturing processes such as laser powder bed fusion, the build orientation and packing of components affect the required support structures, the number of parts in each build, and the surface roughness of the printed parts, among other factors. Maximising the packing density while minimising the build height can increase effective machine utilisation and decrease per-part cost. Yet, the build layout optimisation problem is highly nonlinear and difficult to solve using human intuition, so a systematic algorithm approach is required. Here, we present and demonstrate a voxel-based analysis method with Bayesian optimisation for determining component build orientation in additive manufacturing. We introduce selected case studies incorporating exemplary process attributes of laser powder bed fusion, including the determination of orientation and packing configurations based on support removal and tool-accessibility constraints. [ABSTRACT FROM AUTHOR]

Surface pattern formation of Smart Cut™ silicon-on-insulator (SOI) substrates is investigated using a new process derived from this technology. The local control of SOI surface roughness is achieved by using hetero-temperature surface activated bonding to introduce locally bespoke shear stresses into bonded silicon wafers. The finite element method is used to back up experimental measurements of these large deformations to determine the amount of shear stresses introduced into the structure, and to determine its impact on the fracture mechanism. [ABSTRACT FROM AUTHOR]

Investigating the phonon-surface scattering mechanism is essential for the evaluation of thermal transport in nanostructures. The theoretical description to quantify this mechanism remains to be developed at the atomic scale. This work presents a phonon wave packet method to study the phonon-surface scattering behavior at rough surfaces. We obtain the specularity distribution dependent on phonon polarization, wavelength, and surface roughness. The reflection of the diffuse wave packet is primarily attributed to the surface shadowing effect at a higher incident angle, surface disorder, and surface-induced localized modes. Taking the wavevector-dependent specularity data as input, the thermal conductivity of silicon nanowires is calculated based on the Boltzmann Transport Equation. Our specularity model provides an accurate evaluation for predicting thermal conductivity. This work offers an atomic-level analysis for phonon-surface interaction, which is helpful for the understanding of thermal transport in nanostructures. [ABSTRACT FROM AUTHOR]

This study investigates the interface between ice and organic solvents using atomic force microscopy (AFM). Atomically flat ice surfaces were prepared and observed by AFM in 1-octanol, 1-hexanol, and 1-butanol. The results show differences in surface roughness influenced by the interaction of ice and alcohols. Young's modulus of ice was analyzed by force curve measurements, providing valuable insights into the properties of ice in liquid environments. The results showed the characteristics of the ice surface in different solvents, suggesting potential applications in understanding surface and interface phenomena associated with ice under realistic conditions. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the influence of finishing, polishing, and glazing on the roughness, flexural strength, and microstructure of lithium disilicate glass-ceramics. Materials and Methods: LD CAD/CAM blocks were cut into 96 discs (1.2 x 12 mm). After crystallization, a layer of glaze was applied to the discs' surfaces. The specimens were randomly divided into eight groupsn = 12) for different surface treatments (glaze [G], diamond abrasion [D], find diamond abrasion [F], and polishing [P]): G(glaze, control), GD, GDG, GDP, GF GFG, GFP, and GDFP. Mean roughness (Ra), mean square height (Rq), and maximum roughness (Rz) were measured. The biaxial flexural strength test was performed in a universal testing machine at 0.5 mm/minute. Microstructural analysis was performed using x-ray diffraction patterns (XRD). Differences on the roughness obtained in distinct groups was analyzed with Kruskal-Wallis and Bonferroni tests (α = .05). The flexural strength tests were compared with one-way ANOVA. Results: Glazed groups (G, GDG, and GFG) presented the lowest surface roughness, lower crystallinity, and higher flexural strength than the other groups. Although polishing and glaze presented similar surface roughness, polishing protocol decreased the flexural strength compared to the control group G. Conclusions: Clinically adjusted LD glass-ceramic restorations should be reglazed whenever possible to improve strength. [ABSTRACT FROM AUTHOR]

Purpose: To propose and evaluate standardized polishing protocols for in vitro experiments using a custommade apparatus under controlled force to create consistent surface roughness on titanium and zirconia discs. Materials and Methods: A total of 160 discs were manufactured with a diameter of 10 mm, 80 titanium (Ti) and 80 zirconium oxide (Zr). Specimens were categorized into two groups: controlled force (CF) and without controlled force (WCF). Specimens in the CF group were polished with a custom apparatus incorporating a tension gauge on the Ti and Zr disc surfaces to achieve consistent roughness. The WCF group was polished without the use of a tension gauge. Each group had four subgroups (n = 10): control/machined with no polishing (C), rough (R), smooth (S), and very smooth (VS). The subgroups were processed using a sequence of diamond-impregnated polishing burs and polishing paste. Results: The CF group showed consistent surface roughness and a gradual decrease in surface roughness. Control in Ti (Ra = 6.5 ± 0.03 µm) and in Zr (Ra = 5.4 ± 0.04 µm); R in Ti (Ra = 3.5 ± 0.06 µm) and in Zr (Ra = 3.2 ± 0.07 µm); S in Ti (Ra = 1.5 ± 0.04 µm) and in Zr (Ra = 1.1 ± 0.06 µm); and VS in Ti (Ra = 0.05 ± 0.002 µm) and in Zr (Ra = 0.02 ± 0.005 µm). There were significant differences for R, S, and SV under CF and WCF in Ti and Zr surfaces. Conclusions: The specimens polished under control force produced significantly more uniform surface roughness than those polished without controlled force and were produced with a higher degree of consistency. [ABSTRACT FROM AUTHOR]

We present diamond-like carbon (DLC) conversion surfaces to detect particles with energy below 2 keV. Conversion surfaces have been widely applied in measurements of low-energy particles by instruments onboard planetary and heliophysics missions. Their effectiveness is characterized by the efficiency in changing the charge state of the incident particles while maintaining a narrow angular distribution for the reflected particles. DLC as a conversion surface coating material has high conversion efficiency. We developed a conversion surface production process that provides ultra-smooth and ultra-thin DLC conversion surfaces. The process includes substrate preparation through precision cleaning, plasma immersion ion deposition of the DLC film, and diagnostics of the film parameters. The latter includes the measurement of the coating thickness, surface roughness, and the conversion efficiency for ion beams with energy below 2 keV. The process we developed provides the DLC conversion surface coating of repeatable parameters with a mean surface roughness of 3.4 ± 0.2 Å and a mean film thickness of 46.7 ± 0.8 nm uniform across the sample area. Ion beam measurements showed a negative ion yield of 1%–2% for hydrogen atoms and 8%–15% for oxygen atoms with an angular scatter distribution of 10°–20° at full width of half maximum. These results agree with those of other conversion surface coatings in the literature. The DLC conversion surfaces presented here are implemented in the conversion surface subsystem of the Interstellar Mapping and Acceleration Probe (IMAP)-Lo instrument of the IMAP mission scheduled for launch in 2025. [ABSTRACT FROM AUTHOR]

Coarse-grained (CG) molecular models greatly reduce the computational cost of simulations allowing for longer and larger simulations, but come with an artificially increased acceleration of the dynamics when compared to the parent atomistic (AA) simulation. This impedes their use for the quantitative study of dynamical properties. During coarse-graining, grouping several atoms into one CG bead not only reduces the number of degrees of freedom but also reduces the roughness on the molecular surfaces, leading to the acceleration of dynamics. The RoughMob approach [M. K. Meinel and F. Müller-Plathe, J. Phys. Chem. B 126(20), 3737–3747 (2022)] quantifies this change in geometry and correlates it to the acceleration by making use of four so-called roughness volumes. This method was developed using simple one-bead CG models of a set of hydrocarbon liquids. Potentials for pure components are derived by the structure-based iterative Boltzmann inversion. In this paper, we find that, for binary mixtures of simple hydrocarbons, it is sufficient to use simple averaging rules to calculate the roughness volumes in mixtures from the roughness volumes of pure components and add a correction term quadratic in the concentration without the need to perform any calculation on AA or CG trajectories of the mixtures themselves. The acceleration factors of binary diffusion coefficients and both self-diffusion coefficients show a large dependence on the overall acceleration of the system and can be predicted a priori without the need for any AA simulations within a percentage error margin, which is comparable to routine measurement accuracies. Only if a qualitatively accurate description of the concentration dependence of the binary diffusion coefficient is desired, very few additional simulations of the pure components and the equimolar mixture are required. [ABSTRACT FROM AUTHOR]

Purpose: To analyze the effect of disinfectants on the roughness and mechanical properties of CAD/CAM polymethylmethacrylate (PMMA) dentures. Materials and Methods: Two groups of denture base resins were tested--heat-polymerized and milled blocks. For each resin, 120 specimens were produced for flexural strength (FS) and flexural modulus (FM) analyses (total: 240 specimens), and 40 were produced for microhardness and surface roughness evaluations (total: 80 specimens). They were categorized into the following groups based on immersion: control (deionized water); H1 (1% sodium hypochlorite); H05 (0.5% sodium hypochlorite); and C2 (2% chlorhexidine) groups. The immersion periods were 0 (T0), 130 (T1), and 260 (T2) cycles. Statistical analyses were performed for flexural properties using threeway ANOVA. Microhardness (KHN) and surface roughness (Ra) were analyzed using repeated-measures ANOVA. A significance level of 5% was set. Results: CAD/CAM PMMA showed higher FS (P = .001) and FM (P < .001) than conventional PMMA. The KHN value was superior to the conventional PMMA (P < .001). The chemical solution affected the surface roughness of both resins (P = .007). The CAD/CAM PMMA block showed increased Ra values when H1 was used. Cycling separately increased the FS of conventional PMMA (T1 vs baseline; P < .05). However, the FM of CAD/CAM PMMA was higher (T1 and T2 vs baseline; P < .05). The time factor increased the microhardness of both resins (T2 vs baseline; P < .05). Conclusions: The CAD/CAM resin showed higher values compared to conventional PMMA in all tests, regardless of the chemical solution used; however, the values obtained for both resins were clinically acceptable. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of different finishing protocols on the wear behavior of lithium disilicate glass-ceramics (LD). Materials and Methods: Specimens were produced from LD prefabricated CAD/CAM blocks and divided into three groups according to the surface treatment (n = 8): control, polishing, and glaze. Ceramic specimens were subjected to wear testing using a dual-axis chewing simulator. A 49-N load was applied in the axial direction combined with a lateral movement (1-mm path) using an LD spherical piston for a total of 106 cycles. Qualitative analysis of the wear surface was performed using an optical microscope. Quantitative analysis of surface roughness and volume loss was performed using a confocal microscope and a 3D-image editing software, respectively. Surface roughness and volume loss data were analyzed using Friedman's nonparametric statistical test for repeated measures and the Student-Newman-Keuls test (a = .050). Results: There were statistical differences for surface roughness and volume loss of LD specimens in the different experimental conditions (P < .001). The control and polishing groups showed similar surface roughness and volume loss values for all testing times. The glaze group had greater wear volume after 103, 104, and 105 cycles. After 106 cycles, surface roughness and volume loss were similar in all groups. For the piston, surface roughness was similar over time and among groups. Conclusions: A distinct wear behavior was found for glazed glass-ceramic specimens compared to control and polished specimens. At the end of the simulation, the surface roughness and volume loss was similar for the groups. [ABSTRACT FROM AUTHOR]

Copper (Cu) interconnections have been widely used in advanced electronic packaging due to their outstanding thermal and electric properties. Preparing a smooth and uniform Cu seed thin layer is one of the critical processes to obtain high-reliability Cu interconnections. The barrier layer between Cu and silicon (Si) devices is necessary to prevent the inter-diffusion between Cu and Si. However, little work has been done on the surface roughness analysis of the Cu seed layer deposited on the diffusion barrier layer. In this paper, the influences of deposition thickness, incident energy, barrier layer temperature, and surface morphology on the surface roughness of the Cu seed layer deposited on α-titanium (α-Ti) barrier layer were studied in detail by the molecular dynamics (MD). The simulation results indicated that appropriate parameters have a beneficial effect on reducing the surface roughness, and the surface morphology of the Cu seed layer strongly connects with that of the barrier layer. These results provided a foundation for optimizing the quality of the Cu seed layer. [ABSTRACT FROM AUTHOR]

We have measured the absolute doubly differential angular sputtering yield for 20 keV Kr+ impacting a polycrystalline Cu slab at an incidence angle of θi = 45° relative to the surface normal. Sputtered Cu atoms were captured using collectors mounted on a half dome above the sample, and the sputtering distribution was measured as a function of the sputtering polar, θs, and azimuthal, ϕs, angles. Absolute results of the sputtering yield were determined from the mass gain of each collector, the ion dose, and the solid angle subtended, after irradiation to a total fluence of ∼1 × 1018 ions/cm2. Our approach overcomes shortcomings of commonly used methods that only provide relative yields as a function of θs in the incidence plane (defined by the ion velocity and the surface normal). Our experimental results display an azimuthal variation that increases with increasing θs and is clearly discrepant with simulations using binary collision theory. We attribute the observed azimuthal anisotropy to ion-induced formation of micro- and nano-scale surface features that suppress the sputtering yield through shadowing and redeposition effects, neither of which are accounted for in the simulations. Our experimental results demonstrate the importance of doubly differential angular sputtering studies to probe ion sputtering processes at a fundamental level and to explore the effect of ion-beam-generated surface roughness. [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]

Epitaxial Mn-doped indium tin oxide (ITO) films were deposited on single-crystal yttria stabilized zirconia (YSZ) substrates with (111), (110), and (100) crystal plane orientations using RF magnetron sputtering. The epitaxial relationship between the Mn-doped ITO films and the YSZ substrates was studied using x-ray diffraction (XRD) patterns in the ω–2θ scan mode and XRD pole figures. The Mn-doped ITO films on the YSZ(111) and YSZ(110) substrates exhibited a higher degree of crystallinity than the film on the YSZ(100) substrate as per the x-ray rocking curves. Fluctuations in the crystalline alignment were found to significantly influence the electrical properties of Mn-doped ITO films. Ferromagnetic hysteresis loops were observed at room temperature for all the epitaxial Mn-doped ITO films, irrespective of their crystallographic orientation. The magnetic properties of the epitaxial Mn-doped ITO films suggest that a combination of delocalized charge carrier-mediated interaction and bound magnetic polaron-driven interaction is required to explain the origin of ferromagnetism in these films. The Mn-doped ITO film on the YSZ(111) substrate exhibited the most desirable characteristics in terms of crystallinity, surface smoothness, electrical conductivity, and magnetic properties. [ABSTRACT FROM AUTHOR]

Cerium oxide (CeO 2) is a primary abrasive frequently used in quartz glass polishing slurry for facilitating glass surface planarisation. However, due to its exorbitant synthesis costs and extremely corrosive as well as toxic reagents in the system, the chemical modification of CeO 2 abrasives have limited practical applications. In this work, a novel chemical mechanical polishing slurry for quartz glass incorporating potassium oleate (KOL), deionised water (DIW), cerium dioxide and molybdenum disulphide (MoS 2) was developed in this paper to enhance the chemical mechanical polishing (CMP) performance of CeO 2 -based polishing slurry. KOL creates an alkaline environment for the system, further develops silicate insoluble substances on the quartz glass surface and boosts the material removal rate (MRR) in CMP. MoS 2 exhibits a two-dimensional layered nanosheet structure between the abrasive and quartz glass, and then acts as a solid lubricant to prevent excessive mechanical damage, thus increasing the abrasive's wettability. This characteristic helps avoid scratches and other defects on the quartz glass surface. Notably, when the content of KOL and MoS 2 in the system is 0.2 wt% and 0.3 wt%, respectively, the surface roughness of the quartz glass surface is 0.48 nm under the scanning area of 15 × 15 μm2 and the MRR is 24.03 μm/h following CMP. The synergistic interaction between CeO 2 and MoS 2 significantly enhances the abrasive performance on the glass substrate, offering a novel approach for developing polishing fluids that leverage the collaborative effects between abrasives and two-dimensional materials. [ABSTRACT FROM AUTHOR]

In this study, Fe 80 Ce 20 films were deposited on Si(100) and glass substrates using sputtering in a high-vacuum environment and subsequently heat-treated in a vacuum annealing furnace. The films, with thicknesses ranging from 10 nm to 50 nm, were annealed at temperatures of 100 °C, 200 °C, and 300 °C. The objective was to investigate the effects of film thickness and annealing temperature on the structural, surface energy, and magnetic properties of the material. X-ray diffraction (XRD) analysis confirmed the crystalline nature of both Si(100)/Fe 80 Ce 20 and Glass/Fe 80 Ce 20 films. Atomic force microscopy (AFM) revealed a smooth film surface that became rougher after annealing. Contact angle measurements indicated hydrophilic properties, with the highest surface energy observed in the as-deposited films due to a higher density of defects and grain boundaries. The hysteresis loop demonstrated exceptional soft magnetic properties and a high saturation magnetization (Ms) of approximately 2000 emu/cm³. Annealing at 100 °C altered the magnetic domain structure from a striped labyrinthine configuration to an aligned pattern. At higher annealing temperatures, the films exhibited grain growth, increased surface roughness, and new grain formation. Following annealing, the grains in the Fe 80 Ce 20 films became larger, surface roughness increased, and the water contact angle increased, rendering the films more hydrophobic. The as-deposited films displayed the highest surface energy due to the high density of defects and grain boundaries. Increased surface roughness led to more grain boundary defects and irregularities, which served as pinning points for magnetic domain walls, thus increasing coercivity (Hc). Rough surfaces induced local stress fields, increased magnetic anisotropy, and decreased saturation magnetization. Thermal perturbations from higher annealing temperatures further disrupted the alignment of the magnetic moments, leading to a reduction in saturation magnetization. [ABSTRACT FROM AUTHOR]

The influence of barium oxide on glazes in the SiO 2 -Al 2 O 3 -CaO-MgO-K 2 O system was investigated. Samples were prepared with 0, 2.5, 5 and 7.5 wt% of barium oxide added to this system. The glazes were fired at 1240 °C and the structure and surface properties were determined. Qualitative and quantitative analyses of phase composition, surface properties, structural mid-infrared analysis, and microstructure were performed. Diopside was detected in all glazes as the MgO content was higher than 2.5 wt%. Hyalophane crystals were observed when the BaO content increased to 5 wt%. Mid-infrared studies showed that the appearance of crystalline phases ordered the structure of the glazes; on the other hand, the amorphous phase increased its disorder related to the higher amount of modifying barium cations. The addition of barium oxide did not significantly affect the color of the surface but caused an increase in roughness due to surface crystallization. The microhardness increased with an increased amount of barium in the amorphous phase. [ABSTRACT FROM AUTHOR]

Epoxy-nanomaterials offer a promising solution to combat corrosion threatening civil infrastructure. To examine the impact of nano silica on corrosion resistance, varying amounts of nano silica, ranging from 0.0 to 3 wt%, were introduced into the epoxy matrix. Mechanical properties were studied through studying the dog-bone tensile strength and tribological aspects were assessed through mass loss abrasion tests. Corrosion resistance performance was studied using electrochemical impedance spectroscopy (EIS) and salt spray tests. Nano structure of the coated specimens was studied after salt spray tests using SEM-EDX analysis. Micro Chromatography (M-Ct) technique was employed to investigate the pore formation in the epoxy matrix. Besides, atomic force microscopy (AFM) was introduced to study surface roughness. The test results displayed a notable improvement (5–10 %) in tensile strength upon the introduction of nano silica. Taber tester results showed a reduction in mass loss with the addition of nano silica. Electrochemical impedance spectroscopy (EIS) studies further established a significant increase in corrosion resistance, having an impedance of 12 GOhm.cm2 for epoxy matrix samples containing 2.5 % nano silica after a 768-h salt spray test. SEM-EDX analysis revealed the absence of iron content in the epoxy matrix reinforced with uniformly distributed nano silica. Surface roughness assessments illustrated that nanolaminates contributed to an increase in overall roughness, minimizing surface irregularities in the epoxy matrix. Micro-CT scanning results proposed a decrease in epoxy matrix porosity upon the addition of nano silica. AI based prediction model helped to understand the relationship between surface roughness and corrosion. In summary, the experimental findings suggest valuable insights for future advancements in the development of protective coatings for worldwide civil infrastructures. [ABSTRACT FROM AUTHOR]

SiCp/Al composites are widely used in the aerospace field due to their excellent properties. However, the huge difference in the properties of silicon carbide and aluminum matrix materials can easily lead to machining defects. Ultrasonic vibration-assisted machining is an effective method to deal with difficult-to-machine materials. In this study, ultrasonic elliptical vibration is applied to the helical milling of SiCp/Al composites. Firstly, the ultrasonic elliptical vibration-assisted helical milling (UEVHM) cutting-edge trajectory is modeled, and the equation of the UEVHM tool-chip separation condition is established, which lays a foundation for the analysis of the cutting mechanism. Then, the influence of ultrasonic elliptical vibration on the removal mechanism of SiCp/Al composites was investigated by finite element simulation. It was found that UEVHM can reduce the tearing of aluminum matrix and reduce the hole damage by changing the direction of the cutting velocity and the relative position of the cutting edge and particles. Finally, the single-factor experiment was carried out, and the surface morphology and roughness of HM and UEVHM were compared. The influence of process parameters on the surface roughness of UEVHM was analyzed. The experimental results show that compared with HM, UEVHM can reduce surface defects and exit damage, to obtain better surface roughness and exit edge quality. The increase in cutting speed can reduce the roughness, and the increase in pitch and revolution speed will increase the surface roughness. [ABSTRACT FROM AUTHOR]

Continuous research in the field of metal additive manufacturing has led to the need for constant improvement of manufacturing parameters especially in the case of FDM (Fused Deposition Modeling) manufacturing. In recent years, the main directions outlined for productivity and quality improvement were related to higher printing speed and the use of ironing-type processes. This article aims to study the manufacturing parameters of the dimensional accuracy and surface quality of FDM-manufactured 316L stainless steel. The degree of novelty is given by the application of the ironing process for the green part. A full factorial 33 experimental design was designed for this study, in which the factors studied were ironing angle, ironing speed, and layer spacing during ironing. The dimensional accuracy and surface roughness were analyzed by means of deviation measurement from CAD to the green part and final part after the sintering process. Using the design of experiments offers the possibility of applying the analysis of variance (ANOVA) which provides information about the degree of influence of each of the studied factors. The results obtained for the dimensional accuracy showed that the ironing direction had the biggest influence on the Z-axis shrinkage. Overall, approximately 6% shrinkage in the Z and Y directions was obtained while in the X directions, the shrinkage percentage was around 20%. Surface roughness showed an improvement with higher ironing speeds for the green part while for the sintered part the most significant factor was ironing spacing. [ABSTRACT FROM AUTHOR]

At present, wire sawing technology is the primary slicing method used for certain brittle materials, including monocrystalline silicon, sapphire, and silicon carbide. The surface quality of the sawn wafers significantly impacts subsequent machining processes, such as grinding and polishing. A theoretical model was developed to predict the amount of material removed per unit length of wire during the slicing of circular workpieces by a wire saw with reciprocating and rocking functions. Experiments were conducted during this study in which crystal ingots were sliced using a multi-wire saw, and the amount of material removed per unit length of wire was determined at different cutting positions on the workpiece cross-section. The surface roughness of each crystal wafer was measured systematically. The experimental results revealed that the surface roughness values measured at different points at the same y-coordinate position on a single wafer were approximately equal. However, the surface roughness was greatest on both the initial and final cutting edges and gradually decreased toward the wafer center. The surface roughness was also greatest for the wafer cut nearest to the new wire side, though it gradually decreased for wafers cut nearer to the center of the workpiece and remained relatively consistent from the middle wafer to the wafer cut nearest to the used wire side. The results also indicated that both the material removed per unit length of wire and the surface roughness of the wafer decreased with increases in the wire speed. The relationship between the material removed per unit length of wire and the surface roughness was approximately linear. When the material removed per unit length of wire was set to 0.00333 mm3/m, the average wafer surface roughness was 0.45 μm. [ABSTRACT FROM AUTHOR]

Molten calcium-magnesium-alumina-silicate (CMAS) corrosion has become a major constraint for the application of YSZ thermal barrier coatings (TBCs). In this paper, Al 2 O 3 and YSZ-Al 2 O 3 protective layers with a thickness of 50 μm were prepared on the surface of 8YSZ TBCs using air plasma spraying technology, and the progressive damage modes of the different TBCs under CMAS exposure were investigated, and the effects of the composition and microstructure of the protective layers on the infiltration and wetting behaviour of CMAS were compared. When the exposure time was shorter, the dense YSZ-Al 2 O 3 had a better impermeability barrier effect. As the interaction time between CMAS and the coating was prolonged, the structure and phase stability of YSZ-Al 2 O 3 were damaged, the thickness was thinned, and Al 2 O 3 had better stability and showed better protective effect. CMAS wettability was mainly related to the roughness of the coating surface, and the wettability was poorer on rough surfaces. [ABSTRACT FROM AUTHOR]

Magnesium-doped zinc oxide thin films were dip-coated onto porous ceramic and glass substrates under identical conditions (50 layers, same doping ratio). Structural, morphological, and photocatalytic properties were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), UV–visible spectrophotometry, and confocal microscopy. XRD analysis indicated a shift in peak positions towards higher angles, increased grain size, and lattice distortion on both substrates. Unique flower-shaped crystalline granulates were observed exclusively on the ceramic substrate (DD3Z). The energy gap decreased on the ceramic and increased on the glass substrate. The photocatalytic activity was evaluated using an aqueous orange II solution, showing significantly higher decomposition (80 ± 0.53 % after 6 h) on the ceramic compared to the glass substrate (30 %). The enhanced performance on ceramic substrates, particularly with DD3+ZrO 2 , was attributed to increased microporosity, surface roughness, and active material incorporation, facilitating greater photocatalytic efficiency. The findings suggest promising applications of these materials for efficient and cost-effective photocatalysis, with potential for reuse after thermal treatment at 500 °C. [ABSTRACT FROM AUTHOR]

The petal effect is a well-known natural phenomenon in surface science and has served as inspiration for the creation of several materials with superhydrophobic qualities and high adhesion. As surface roughness has a crucial role in these properties, being able to modulate it could help us design materials at will. Capillary penetration frustrates diffusion and promotes large contact angles as well as high adhesion. Polystyrene surfaces were created using the spin-coating technique. By varying the polymer concentration, the surface roughness was modified. To determine the roughness parameters, atomic force microscopy was used. We recorded advancing and receding contact angles using water and glycerol as test liquids to study contact angle hysteresis, the work of adhesion and the apparent surface energy, which was determined with the Chibowski and Perea–Carpio method. For the purpose of elucidating the wetting states, captive bubble experiments were conducted. Using an easy method, we create polystyrene surfaces with both superhydrophobicity and strong adhesion, where the roughness area factor regulates wetting transitions from Cassie–Baxter to Wenzel. The receding contact angle suggests capillary penetration, which we demonstrate by captive bubble experiments. In addition, a link was found between the surface roughness and apparent surface energy. [ABSTRACT FROM AUTHOR]

Surface roughness control of end products is increasingly becoming significant, especially with the miniaturization trends in the semiconductor industry. Ultra-thin amorphous carbon (a-C) films offer a prime solution to optimize surface roughness due to their outstanding characteristics. In this study, hydrogenated a-C films are deposited on two-dimensional quartz plates and three-dimensional quartz molds to evaluate the growth mechanisms and changes in the surface roughness, which is supported by molecular dynamics simulations. Results reveal that surface roughness encounters multiple variations until it reaches stable values. These fluctuations are categorized into four different stages which provide a concrete understanding of various growing mechanisms at each stage. Different behavior of the atoms in the top layers is recorded in the cases of normal and grazing incidents of carbon atoms. Lower surface roughness values are obtained at low-angle deposition. Interestingly, surface smoothing is attained on the sidewalls of the nanotrench mold where the deposition occurs with high incident ion angles. [ABSTRACT FROM AUTHOR]

A new hybrid finishing process, namely, double-disc chemical-assisted magnetorheological finishing (DDCAMRF) process has been developed for the polishing of monocrystalline silicon wafers combining the benefits of the two processes namely, chemical–mechanical polishing (CMP) and magneto-rheological finishing (MRF). In the present work, the bonding between the Si atoms gets weakened by the chemical action which further softens the work surface while the rotation of MR fluid provides the desired mechanical force which assists in the removal of material from the work surface. An experimental setup for the hybrid finishing has been designed and fabricated for achieving the nanometric finishing of silicon substrates. Also, the process was further established by carrying out the experimental study which involves analyzing the influence of different process factors viz., polishing speed, % CIP concentration, slurry flow rate, and working gap, on the surface roughness (Ra) of a monocrystalline silicon wafer. An improvement of over 88.96% was observed in the surface roughness of a silicon wafer and a nearly mirror-like finish was observed while carrying out the polishing with the developed DDCAMRF process. The developed process resulted in enhancing the process performance ensuring better surface finish (i.e., with minimal defects) and reduced polishing time compared to different polishing techniques available. [ABSTRACT FROM AUTHOR]

The effect of surface roughness and temperature on wettability of polyethylene terephthalate (PET) melt on steel substrates is assessed. A plot of contact angle, Φ, Vs. time, τ, revealed the significant effect of temperature on wetting compared to surface roughness. The surface free energy of the steel substrate decreased by about 22% with increase in surface roughness from 0.21 to 3.8 μm. The measured surface tension of the polymer melt was 31.36 mN m−1 at 260°C. The variation in the cooling rate of the solidifying molten PET resulted in varying degree of polymer opacity. The opacity variations were quantified as a function of pixel intensity. The opacity of the solidified PET melt drops sharply declines at lower cooling rates before stabilizing at higher rates. No significant difference in the mean pixel intensity is observed between PET melts solidified at different substrate temperatures. Three distinct regimes in PET melt solidification are identified: (i) increased crystallization propensity at lower cooling rates (<8°C min−1), (ii) dominance of amorphous characteristics at higher rates (>199°C min−1), and (iii) a transitional regime at intermediate cooling rates. [ABSTRACT FROM AUTHOR]

Fused-silica-based microlens array (MLA) has excellent stability in the harsh environment. However, it is still a challenge to efficiently prepare superhydrophobic quasi-periodic MLA and keep the optical performance of the microlens. In this paper, we proposed spatial modulated picosecond laser parallel processing method to prepare a superhydrophobic quasi-periodic MLA on fused silica. By using a spatial light modulator, the picosecond laser was shaped to multi-focal spots and line-shape beam, respectively, which improved the fabrication efficiency. The line-shape beam was the key to induce micro-nanostructures on the smooth MLA and keep the optical performance of the microlens. The results showed that the surface roughness of the microlens region was less than 100 nm. Combing with shaping picosecond laser processing and chemical treatment, the superhydrophobic MLAs showed the excellent anti-fogging and self-cleaning properties. The average contact angle of the superhydrophobic MLAs was 162.3°. The superhydrophobic MLA showed low adhesion to water droplet (<10 μN) and low contact angle hysteresis (2.1° ± 0.7°). We believe shaping picosecond laser parallel processing method is a flexible and low-cost approach to prepare superhydrophobic micro-optical elements on fused silica. [ABSTRACT FROM AUTHOR]

The non-destructive testing for subsurface damage of processed silicon nitride ceramics is significant to the improvement of processing technology and evaluation of product performance. A novel method for the measurement of subsurface damage based on dispersion of laser-excited surface acoustics wave is proposed in this paper. The subsurface damage distribution is quantified as the damage density and depth of the damage layer. The forward model of surface acoustics wave propagation in damage layer is derived by the stiffness matrix method. Bayesian inversion is applied to estimate model parameters and uncertainties of subsurface damage from the experimental dispersion data. Laser ultrasonic experiments are carried out on four samples with different substrate material parameters and surface qualities to demonstrate the feasibility of the method for detecting varying degrees of subsurface damage. The results prove that with reasonable use of prior information about damage depth predicted by surface roughness, subsurface damage with a depth ∼10 times smaller than the minimum wavelength of surface acoustics wave is accurately characterized. The reliability of the results is further verified by Vickers microhardness tester. [ABSTRACT FROM AUTHOR]

Because oil and gas pipelines reside in high-temperature, high-pressure and highly acidic environments for a long time, it is very common for such pipes to experience corrosion thinning. To solve the long-term online monitoring problem of piezoelectric ultrasonic dry coupling of monitored objects with different surface roughnesses, the effects of different thicknesses of silver plates, different surface roughnesses and different coaxial loads on piezoelectric ultrasonic dry coupling were studied here. To improve the low SNR of the acquired signal, a Batworth high-pass filter and zero-phase digital filter are proposed for online ultrasonic monitoring. The effects of three kinds of roughness and axial load on the piezoelectric ultrasonic dry coupling signal are studied, and the relationship between the roughness, thickness of the silver plate and axial load is obtained. The results show that under different roughness conditions, the SNR of the ultrasonic signal increases with increasing axial load. When the axial load reaches a certain magnitude, the SNR of the ultrasonic signal tends to be stable. When the surface roughness is Ra = 1.6 µm and the thickness of the silver plate is 0.05 mm, the SNR of the ultrasonic signal reaches the best value, and the required axial load is minimal. [ABSTRACT FROM AUTHOR]

N-polar GaN film was obtained by using a high-temperature AlN buffer layer. It was found that the polarity could be inverted by a thin low-temperature AlN interlayer with the same V/III ratio as that of the high-temperature AlN layer. Continuing to increase the V/III ratio of the low-temperature AlN interlayer, the Ga-polarity of GaN film was inverted to N-polarity again but the crystal quality and surface roughness of GaN film greatly deteriorated. Finally, we analyzed the chemical environment of the AlN layer by x-ray photoelectron spectroscopy (XPS), which provides a new direction for the control of GaN polarity. [ABSTRACT FROM AUTHOR]

This article aims to evaluate and compare two types of organic surface-modified-nanoclay of octadecylamine-modified-bentonite-nanoclay (ODA-BNC) and aminopropyltrimethoxysilane-octadecylamine-modified-nanomontmorillonite (APS-ODA-MMT). Each type of nanoclay is combined with silica as a bi-filler for natural rubber (NR)/ethylene propylene diene monomer rubber (EPDM) in a 50/50 blend ratio for possible vulcanized rubber nanocomposite application. The total filler content is 50 phr while nanoclay filler content ranges from 0 to 20 phr, keeping the other ingredients ratio fixed. The prepared composites are characterized by the Fourier transform infrared spectrophotometer (FTIR) and their mechanical and thermal properties are thoroughly investigated. The data reveal that the fillers added to the rubber can improve its surface properties according to their type and amount as confirmed by the Atomic force microscope (AFM), and Scanning electron microscope (SEM) investigation. The surface of rubber containing APS-ODA-MMT displayed higher height (251) and roughness surface (94.11), than those (69.8) and (45.62) respectively, containing ODA-BNC. Moreover, the acid resistance of the prepared composites is verified and indicated that increasing the nanoclay ratio (20%) enhances the acid resistance by reducing the surface distortion while keeping the surface morphology. The mechanical properties and Thermogravimetric Analysis (TGA) measurements showed that the rubber containing ODA-BNC has higher values of stress (2.2), elongation (975), and thermal stability (470, 505, 520°C) than those (1.75), (650), and (440, 460, 470°C) respectively, containing the APS-ODA-MMT. Moreover, the durability investigation of the vulcanized rubber via the AFM found the modified composites can be used in harsh environments as a covering layer in petrochemical networks or chemical factories. [ABSTRACT FROM AUTHOR]

The papermaking, packaging, and printing industry are actively seeking sustainable material alternatives to address growing concerns about environmental consciousness and finite resources. Synthetic latex, a frequently utilized binder in paper coating formulations, present difficulties due to their dependence on fossil fuel resources and their reduced recyclability in comparison to eco‐friendly sustainable products. In this study, synthetic latex was replaced with a starch‐based nanoparticle (starch NP) binder at a 1:1 ratio in a coating formulation. Printing trials to assess colorimetric characteristics was made using electrophotography (EP) printing, given the current upward trajectory and expansion of EP technology into the label, packaging, and folding carton sectors. The in‐depth investigations reveal that incorporating starch NP binder result in improved optical, color, and dot characteristics. Moreover, it maintains consistent and comparable coefficients of friction. Partial replacement of synthetic latex with the starch NP binder yields significant enhancements in surface roughness and text quality. Importantly, the starch NP binder not only improves the dielectric relaxation properties of the paper and enhances toner transfer but also accelerates the distribution of the electrical field compared to synthetic latex, optimizing toner transfer and thereby enhancing color gamut volume. The study demonstrates that employing the starch NP binder leads to substantial improvements in colorimetric performance without any drawbacks in EP printing, making it highly advantageous to replace 50% of the synthetic binder. [ABSTRACT FROM AUTHOR]

Public transport via trams has become increasingly important in daily life to meet the growing demand for economic and environmental considerations. In order to ensure the safety of the railway system and reduce service costs, it is necessary to understand the tribological behavior of the system. There are various types of damage such as fatigue, wear, and cracking that can harm the wheels and rails. To determine the wear mechanisms and identify the situations in which wear movements occur, it is crucial to monitor factors such as temperature, surface roughness, and contact micro-hardness between the wheel and the rail. The objective of this study is to analyze the tribological behavior and the impact of climatic conditions on the wheel–rail contact system in the desert area of the Ouargla tramway in Algeria. To achieve this, an intelligent sensor programmed by a microcontroller was utilized to measure the temperature of the wheel–rail contact. Additionally, a hardness tester was used to measure the micro-hardness of the rail, and a roughness tester was utilized to monitor the surface condition of the rail. The measured temperature values during the passage of the tramway varied between ambient temperature and a temperature of 450∘C. The micro-hardness values ranged from 270 Hv to 440 Hv, and the roughness values varied between 0.4 μ m and 2.7 μ m. [ABSTRACT FROM AUTHOR]

Superalloys go through cyclic oxidation which refers to the progression of reputed exposure of materials to alternating oxidizing and non-oxidizing environments at high temperatures. The oxidation behavior of cobalt-based superalloy coatings depends on several variables, including the environment, surface roughness, manufacturing conditions, & coating composition. Because of their higher temperatures and protective oxide layer, coatings with a greater cobalt concentration are more oxidation-resistant. The behavior of oxidation is influenced by surface roughness, where rough surfaces offer greater surface area to oxidation while smooth surfaces decrease interaction with the environment. The microstructure and porosity of the coating are further impacted by processing variables used in thermal spraying, including temperature, particles velocity, and spray distance. Adding reactive components to the coating composition, such as silicon and aluminum, and applying post-treatments like nitriding or sealing are two ways to increase oxidation resistance. A greater temperature and particle speed can lead to a denser with less porous covering, improving the oxidation process resistance. The two typically used heat spraying techniques are high-velocity oxy-fuel (HVOF) and plasma spraying. To increase the resistance to oxidation of thermal spray cobalt-based superalloy coating, some strategies have been devised, such as inclusion of reactive materials, such as aluminum and silicon, which is the coating composition. These elements may establish an oxide layer protecting the coating's appearance, preventing further oxidation. [ABSTRACT FROM AUTHOR]

This research explores the intricate dynamics of machining nickel-based single crystal superalloys, with a focused examination of the principal parameters influencing grinding forces and surface roughness. It marries micro-scale grinding simulations with sophisticated Support Vector Machine (SVM) modeling in Matlab, conducting an in-depth analysis of how variables such as grinding depth, abrasive grain size, spindle speed, and feed rate affect the surface integrity of these premium materials. The introduction of the SVM model represents a novel contribution to the field, undergoing extensive validation against traditional predictive methods and demonstrating superior predictive accuracy. Detailed investigation into grinding parameters uncovers a significant link between process variables and the microstructural alterations on the alloy's surface, leading to the determination of grinding conditions that substantially enhance surface quality. The accuracy of the SVM model in predicting surface roughness, evidenced by a Mean Squared Error (MSE) of 9.9662e-05 and an R-squared value of 99.9992%, positions it as a pivotal tool for process optimization. This, in turn, offers substantial advantages for precision engineering in aerospace component manufacturing. The findings underscore the transformative impact of SVM-based modeling in realizing exceptional performance in the machining of complex materials. [ABSTRACT FROM AUTHOR]

In order to improve the quality and efficiency of the sheet grinding and reduce the problems of distortion, local overwear, and ununiformity induced by grinding, an experimental study on the grinding of the sheet was carried out based on electromagnetic drive—the magnetic abrasive tool (MAT). Based on nonlinear fitting between the surface roughness Ra values and the variables, the microcomputer controls the current to form a transmission magnetic field-driven—the MAT—on the surface of the sheet to analyze the force and explore the force of the MAT and the characteristics of the movement, and find the core structure of the electromagnet and the coil layout of the better parameters. The MAT grinding method based on the electromagnetic drive was carried out for machining the SUS304 sheet workpiece, and the effect of current, machining gap, and magnetic field conversion frequency was analyzed. Based on the experimental study, the mathematical model was built, and the optimized combination of process parameters was validated and verified. The response surface methodology (RSM) was used for experiment design; the optimized combination of process parameters was derived as follows: current 0.72A, machining gap 0.93 mm, and magnetic field conversion frequency 149 ms. The MAT grinding with the electromagnetic drive the surface of the sheet, there is no local overwear phenomenon, the grinding surface is smooth and even, the micro-morphology and uniformity are well, and the mill efficiency is improved, which is a more significant advantage compared with the traditional grinding method. [ABSTRACT FROM AUTHOR]

Environmental awareness has driven a crucial search for biodegradable materials. Over the past few decades, the machining of these materials, particularly through drilling, has garnered significant research interest. This study presents an evaluation of the drilling performance of a hybrid composite (jute/glass), considering factors such as the concentration of chemical treatment with sodium bicarbonate, the type of glass fiber (random or woven), the degree of hybridization between the jute and glass fibers, and cutting parameters like rotation speed, feed rate, and drill diameter. Drilling operations were conducted to determine the maximum temperature in the cutting zone, the surface roughness of the drilled holes, and the maximum delamination factor. A Sobol sensitivity analysis was performed to identify the input parameters influencing these responses studied. Predictive modeling of the results based on the input factors was then conducted using the deep neural network (DNN) and Adaptive Neuro-Fuzzy Inference System (ANFIS) approaches. The results show that the type of glass fiber significantly affects surface roughness, while rotation speed primarily influences cutting temperature. Similarly, the drill diameter directly impacts the maximum delamination factor. Finally, the predictive modeling demonstrates that the ANN-IGWO models provide the best predictions of drilling parameters compared to the ANN-GA and ANFIS models, with mean absolute errors ranging from 1.22 to 12%. [ABSTRACT FROM AUTHOR]

This paper focuses on the difficulties in high-quality and high-efficiency micro-milling nickel-based superalloy micro thin-walled parts. The second-generation Non-dominated Sorting Genetic Algorithm (NSGA-II) is improved. A central composite experiment is designed, and a surface roughness prediction model is developed for micro-milling thin-walled parts. A prediction model for surface residual stress on thin-walled parts is developed using an L9(34) orthogonal simulation experiment. Using the NSGA-II algorithm, the four cutting parameters (spindle speed, feed per tooth, axial cutting depth, and radial cutting depth) are optimized to achieve low surface roughness and high material removal rate, while stable cutting and surface compressive residual stress are considered constraints. Finally, the high-quality and high-efficiency micro-milling of the Inconel 718 cross-shaped thin-walled parts is realized. [ABSTRACT FROM AUTHOR]