Textured Materials Research Articles

Low-cost preparation of 3D-Au@SiO2 substrates for surface-enhanced Raman spectroscopy and finite difference time domain enhancement analysis

Thin films (thickness of ∼2 to 4 μm) comprised of SiO2 particles (300–400 nm) were deposited on glass slides using a screen-printing approach. After annealing, films were functionalized with polyethyleneimine (PEI) to facilitate the adsorption of 3 to 5 nm Au nanoparticles (Au NPs) on the SiO2 particle films, and the resulting Au@SiO2 substrates were used to evaluate their potential for Surface-Enhanced Raman Spectroscopy (SERS) applications. Two types of supported silica particles, monodisperse solid silica (s-SiO2) and textured silica (t-SiO2), were used to investigate the impact of the SiO2 surface properties on the formation of Au NPs hotspots. Monodisperse s-SiO2 particles were synthesized using the Stöber method, while textured surface materials were obtained by incorporating cetrimonium bromide (CTAB) into the solution at a concentration below the critical micelle concentration.SERS studies were conducted using Rhodamine 6G (R6G) as a target molecule. For Au@s-SiO2, the SERS signal results showed a reasonable spatial reproducibility with relative standard deviation values (RSD ∼5 to 16% for studies on six different samples), in agreement with literature values (RSD ∼10 %). In the case of t-SiO2, the spatial reproducibility was also good in some slides with low% RSD between 7 and 12 %, but in other substrates with values as high as 20 % to 50 % RSD. Also, a lower slide-to-slide %RSD value, 26 % vs. 34 %, was found for the s-SiO2 sample.For the Au@t-SiO2 substrates, the estimated calibration sensitivity and the calculated limit of quantification (LoQ) for R6G were 0.392 (log (peak area) vs. log ([R6G]) and 0.381 μM, respectively, close to the visual practical limit. For Au@s-SiO2, the sensitivity was lower, 0.305 vs 0.392, and the LoQ was 0.016 μM, which is lower than the visual practical limit 0.1 μM. To put these results in context, SiO2 and Au@SiO2 films were characterized using different methods, including profilometry, high resolution scanning and transmission electron microscopy (HR-SEM and TEM), UV–visible and Raman spectroscopy.In addition, finite-difference time domain (FDTD) simulations were performed to understand the relationship between substrate morphology and SERS enhancement. Image processing and 3D modelling software were used to convert the HR-SEM images of the SERS substrates into FDTD simulation-compatible models. The simulations showed that the Au@s-SiO2 substrate had a greater average plasmon resonance enhancement over the Au@t-SiO2 substrate, in good agreement with the LoQ differences between substrates, ∼0.02 μM for Au@ s-SiO2 vs. ∼0.4 μM for Au@t-SiO2.

Powder aerosol deposited calcium cobaltite as textured P-type thermoelectric material with power factors approaching single crystal values

In this work, the thermoelectric material calcium cobaltite Ca3Co4O9 (CCO), a promising p-type conducting thermoelectric oxide with anisotropic properties, was processed by the powder aerosol deposition method (PAD) to form a dense ceramic CCO film with a thickness in the µm range. The prepared films were characterized regarding their microstructure and thermoelectric properties between room temperature and 900 °C. After heat treatment at 900 °C, the CCO PAD film in-plane shows excellent properties in terms of electrical conductivity (280 S/cm at 900 °C) and Seebeck coefficient (220 µV/K at 900 °C). The calculated power factor in-plane (ab) reaches with 1125 µW/(m K2) 40 % of the single crystal value, surpassing the known-properties of CCO bulk ceramics. Examination of the microstructure shows a strong fiber texture of the film as well as a strong coarsening of the grains during the first heat treatment up to 900 °C.

3D-printed Ti6Al4V thoracic fusion cage: Biomechanical behavior and strengthening mechanism

To effectively replace diseased and damaged thoracic vertebrae, a series of three-dimensional (3D) printed titanium (Ti) alloy (Ti6Al4V) thoracic fusion cages with varying volume ratio of reinforced scaffolds are designed, and their structure-function relationships are investigated systematically. It is demonstrated that the mechanical strength of fusion cage is gradually enhanced as the scaffold volume increases, which may be attributed to its textural transformation from α phase to β phase. The compressive, shear, and fatigue of fusion cages successfully attain the International Organization for Standardization (ISO 23089), when the scaffold volume ratio exceeds 15%. Furthermore, the biomechanical analyses, including stress distributions and subsidence in flexion, extension, axial rotation, and lateral bending sections of fusion cages, further shed light on their potential clinical applications. This work deeply deciphers the intrinsic connection between biomechanical property and material texture of the thoracic fusion cages, offering valuable insights into their strengthening mechanism, which providing a guidance for the precise design and quick synthesis of other 3D-printed Ti6Al4V implants.

Machine learning enhanced analysis of EBSD data for texture representation

Generating reduced-order, synthetic grain structure datasets that accurately represent the measured grain structure of a material is important for reducing the cost and increasing the accuracy of computational crystal plasticity efforts. This study introduces a machine-learning-based approach, termed texture adaptive clustering and sampling (TACS), for generating representative Euler angle datasets that accurately mimic the crystallographic texture. The TACS approach employs K-means clustering and density-based sampling in a closed-loop iteration to create representative Euler angle datasets. Proof-of-principle experiments were performed on rolled and recrystallized low-carbon steel. Validation of the TACS approach was extended to twenty-two datasets, varying lattice structures, and complex crystallographic textures, thereby encompassing a broad range of materials and crystal structures. Kolmogorov-Smirnov (K-S) test comparisons underscore the performance of the TACS approach over traditional electron backscatter diffraction EBSD dataset reduction techniques, with average K-S test scores nearing 0.9, indicating a high-fidelity representation of the original datasets. In contrast, conventional methods display scores below 0.3, indicating less reliability of the structure representation. The independence of the TACS approach from material texture and its capability to autonomously generate datasets with predetermined data points demonstrates its unbiased potential in streamlining dataset preparation for crystallographic analysis.

Thermal conductivities and complex network properties of fractal self-assembled/self-organized texture in binary composite materials

To investigate the relationship between histological properties and thermal conductivities of binary self-assembled/self-organized fractal materials fabricated by the mixed diffusion of filler particles, the particle group distribution of the filler particles was analyzed. Unlike conventional research on particle size distribution, we performed an analysis that focuses on interactions and connectivity between particles from the perspective of the Barabasi-Albert model. In three complex network systems of β-Si3N4 (SN)/austenitic stainless steel (SUS), SN/piezoelectric polyvinylidene fluoride (PVDF), and BaTiO3 (BT)/PVDF, the size distribution of secondary particles was a power-law distribution until the particle group grew relatively large. In the SN/SUS and SN/PVDF systems, a crossover phenomenon was observed in which the order distribution exhibited a power-law in the region where the particle group area was small, and as the particle group became larger, the order distribution became exponential distribution. On the other hand, the BT/PVDF system deviated from the power law distribution as the particle group area increased but did not exhibit an exponential distribution. The characteristics of the particle group distribution of these filler particles were closely related to thermal conductivity, indicating that the connection of particle groups was important. Furthermore, the relationship between the multifractal capacitance dimension, which is strongly correlated with the distance between the particle groups, and the total number of filler particle groups suggests that the texture of these composite material systems may have both small-world and scale-free properties. We also focused on the relationship between the multifractal and complex network properties of the three particle groups. As a result, a correlation was found between the slope γ, which reflects the characteristics of the power distribution, and the thermodynamic parameter α (corresponding to internal energy change) obtained from multifractals. In particular, the smaller the change in γ relative to the change in α, the more pronounced the bonding of particles and particle groups, while the larger change in γ suggested the dispersion of particle groups.

Assessment of Hydrophilicity/Hydrophobicity in Mesoporous Silica by Combining Adsorption, Liquid Intrusion, and Solid-State NMR Spectroscopy.

We have developed a comprehensive strategy for quantitatively assessing the hydrophilicity/hydrophobicity of nanoporous materials by combining advanced adsorption studies, novel liquid intrusion techniques, and solid-state NMR spectroscopy. For this, we have chosen a well-defined system of model materials, i.e., the highly ordered mesoporous silica molecular sieve SBA-15 in its pristine state and functionalized with different amounts of trimethylsilyl (TMS) groups, allowing one to accurately tailor the surface chemistry while maintaining the well-defined pore structure. For an absolute quantification of the trimethylsilyl group density, quantitative 1H solid-state NMR spectroscopy under magic angle spinning was employed. A full textural characterization of the materials was obtained by high-resolution argon 87 K adsorption, coupled with the application of dedicated methods based on nonlocal-density functional theory (NLDFT). Based on the known texture of the model materials, we developed a novel methodology allowing one to determine the effective contact angle of water adsorbed on the pore surfaces from complete wetting to nonwetting, constituting a powerful parameter for the characterization of the surface chemistry inside porous materials. The surface chemistry was found to vary from hydrophilic to hydrophobic as the TMS functionalization content was increased. For wetting and partially wetting surfaces, pore condensation of water is observed at pressures P smaller than the bulk saturation pressure p0 (i.e., at p/p0 < 1) and the effective contact angle of water on the pore walls could be derived from the water sorption isotherms. However, for nonwetting surfaces, pore condensation occurs at pressures above the saturation pressure (i.e., at p/p0 > 1). In this case, we investigated the pore filling of water (i.e., the vapor-liquid phase transition) by the application of a novel, liquid water intrusion/extrusion methodology, allowing one to derive the effective contact angle of water on the pore walls even in the case of nonwetting. Complementary molecular simulations provide density profiles of water on pristine and TMS-grafted silica surfaces (mimicking the tailored, functionalized experimental silica surfaces), which allow for a molecular view on the water adsorbate structure. Summarizing, we present a comprehensive and reliable methodology for quantitatively assessing the hydrophilicity/hydrophobicity of siliceous nanoporous materials, which has the potential to optimize applications in heterogeneous catalysis and separation (e.g., chromatography).

Modeling hydrogen diffusion in precipitation hardened nickel-based alloy 718 by microstructural modeling

Abstract Environmentally assisted cracking can significantly affect the performance of high strength alloys and limit material selection to minimize the risk of subcritical crack growth in service. UNS N07718 is widely used in marine service applications and under a variety of conditions, such as: alternate immersion, different levels of cathodic protection, and freely corroding galvanic couples, because of its demonstrated corrosion and fracture resistance in these environments. In this work we developed a representative model of the material microstructure including the metal grains, the material texture, and the precipitates along the grain boundaries and within the grains. The microstructural model was subjected to the boundary conditions identified at the notch root of a fracture mechanics sample and the results are used as input for a simulation of hydrogen diffusion from the surface of the notch, assuming the material has been introduced to a hydrogen producing environment. The diffusion of hydrogen was modeled by Fick’s law and included both hydrostatic stress and mobile dislocation velocity as driving forces. The influence of immobile dislocations was also modeled to account for the irreversible trapping. The results show that hydrostatic stress and immobile dislocation trapping can significantly alter the highest concentration of hydrogen and its location within the microstructure towards the fracture process zone. Mobile dislocation velocity has a small influence in determining the hydrogen distribution near the fracture process zone.

DRAGen in Application-An Approach for Microstructural Fatigue Predictions of Non-Oriented Electrical Steel Sheets.

This study investigates multiple cyclic loading scenarios of non-oriented electrical steel sheets through both experimental and numerical approaches. The numerical simulations were conducted using Representative Volume Elements generated with DRAGen. DRAGen allowed for the generation of Representative Volume Elements with a non-cubic shape to cover the complete sheet thickness and enough grains to represent the material's texture. The experimental results, on the other hand, are utilized to calibrate and validate a prediction model, highlighting the significance of accumulated plastic slip as a suitable parameter correlated with fatigue life. Using the accumulated plastic slip from the simulations, a fatigue fracture locus is introduced, which describes a 3D surface dependent on the maximum stress, fatigue life, and the fatigue stress ratio. The study shows reliable results for the fatigue life prediction using the calibrated fatigue fracture locus. While substantial progress has been made in predicting the fatigue life at multiple fatigue stress ratios, notable disparities between experimental and simulation results suggest the need for further investigations regarding the influence of the surface quality. This observation motivates ongoing research efforts aimed at refining simulation methodologies to better incorporate surface roughness effects. In summary, this study presents a validated model for predicting fatigue life in non-oriented electrical steel sheets, offering valuable insights into material behavior at different loading scenarios and informing future research directions for enhanced structural performance and durability.

Morphometric and soil texture analysis of soil material from wasp nests Sceliphron destillatorium (Illiger, 1807) (Apoidea: Sphecidae)

Background. The article presents the data obtained as a result of our research on the nests of an aboriginal wasp species on the territory of Ukraine – Sceliphron destillatorium (Illiger, 1807) that belongs to the family Sphecidae. We collected 54 wasp nests in different regions: Zakarpattia (n = 4), Ivano-Frankivsk (n = 1), Rivne (n = 12) and Lviv (n = 35) Regions. The data are presented as a result of measuring the main morphometric parame­ters of nests (length, width of cells and mass of nests) which are typical of the species under study. The paper also reports the results of the soil texture analysis of the soil material of twelve wasp nests from four different places of “mass nesting” and compares the results with the control samples of the surrounding soils in the corresponding areas. The study aimed at investigating the structure of the nests of S. destillatorium wasps, determining the soil texture of the soil material of nests from different regions of Ukraine and comparing them. Material and Methods. The nests of Sceliphron destillatorium wasps were the object of the study. The morphometric parameters of nests were measured with an automatic digital caliper 0–150 mm and Axis A500 technical chemical scales. The soil texture analysis was performed by the pipette method. The potentiometric method was used to determine the pH of the soil material. In addition, the determination of the CO2 carbonates was carried out according to the volumetric method. Results. We have analysed 54 nests of S. destillatorium. 46 nests were found in “mass nesting places” (in some places several samples were found): in Lviv (3 sites) and Rivne Regions (1 site – Rivne Nature Reserve). The content of granulometric elements was determined in twelve wasp nests from these places and twelve control soil samples were taken around the places of “mass nesting” (three samples of surrounding soil from each location). In order to compare the particle size distribution of elements in all analysed samples (24), we drew cumulative curves and determined coefficients of uniformity and curvature. Conclusions. Nest weighing revealed considerable variations in the mass of the nests – from 10.06 to 222.56 g – depending on the number of cells in a nest. The size of the nests also varied. The number of cells in the nests varied from 2 to 37 (mean = 13; n = 54 nests). As a result of the soil texture analysis of the nest soil material, we determined the percentage of granulometric elements used by the wasps for the construction of their nests. It was found that fine sand was one of the predominant fractions in all twelve nests. The similar content of all five fractions of soil material of wasp nests from different areas indicates that the soil texture of the nests which were built by S. destillatorium probably does not depend on their geographical location.

39‐3: Invited Paper: Kirameki Display: Technical Approaches to Represent Real Texture with Light Fields

We have developed a “Kirameki display” that can represent a real texture of materials. (“Kirameki” means a shining/glittering sense in Japanese.) In addition, we have investigated an improvement of “texture representation” by optimization of both an optical design and a software algorithm. Lastly, we discuss the future technical fields for texture representation on displays.

Accurate distances measures and machine learning of the texture-property relation for crystallographic textures represented by one-point statistics

The crystallographic texture of metallic materials is a key microstructural feature that is responsible for the anisotropic behavior, e.g. important in forming operations. In materials science, crystallographic texture is commonly described by the orientation distribution function, which is defined as the probability density function of the orientations of the monocrystal grains conforming a polycrystalline material. For representing the orientation distribution function, there are several approaches such as using generalized spherical harmonics, orientation histograms, and pole figure images. Measuring distances between crystallographic textures is essential for any task that requires assessing texture similarities, e.g. to guide forming processes. Therefore, we introduce novel distance measures based on (i) the Earth Movers Distance that takes into account local distance information encoded in histogram-based texture representations and (ii) a distance measure based on pole figure images. For this purpose, we evaluate and compare existing distance measures for selected use-cases. The present study gives insights into advantages and drawbacks of using certain texture representations and distance measures with emphasis on applications in materials design and optimal process control.

General design of high-performance and textured layered thermoelectric materials via stacking of mechanically exfoliated crystals

General design of high-performance and textured layered thermoelectric materials via stacking of mechanically exfoliated crystals

Oxidation-induced surface stress on texture development of thin films: The (001) FePt case

Residual stress is an inevitable characteristic in all kinds of thin film materials. The incorporation of stress and physical properties may also be of importance as a stress-driven functional characteristics, particularly in the context of engineering texture and anisotropies in magnetic thin film materials. A mechanism explaining the (001) preferred orientation in the rapidly annealed FePt thin films is proposed on the basis of the experimental study of the oxidation-induced surface stress measurements. By adopting a grazing incidence anomalous x-ray diffraction based on synchrotron radiation, the depth-resolved stress distribution of the FePt films was investigated. A substantial in-plane tensile stress induced by surface oxidation was observed in the FePt thin films. The oxidation layer, with an appropriate thickness, maintains the accumulated tensile stress, thereby inducing the (001) preferred orientation in FePt. The surface stress relaxation was observed in the FePt films with the processes lacking oxygen or in a poor vacuum condition.

Porous asphalt mixture performance in cold regions: Case study of Chicago

Porous Asphalt Mixtures (PAMs) improve resilience of flexible pavements in the context of climate change. PAM application in coastal cities like Chicago is of interest; however severe winters compromise the durability of PAMs given their susceptibility to freeze-thaw. This work aimed to evaluate the to-date experience with PAMs in Chicago, exploring benefits and limitations to be considered for future projects in the Southern Lake Michigan region. Full-depth PAM cores were obtained from seven sections, constructed in different years. Tests were conducted to assess the evolution of surface texture, internal structure, and multi-scale material properties. Regarding surface texture, consistent change over time was observed, such as loss of the “channel” structure, and increase in mean profile parameters because of raveling. Also, binder content varies with time within different layer depths. An aging gradient in terms of stiffness from top to bottom within the layer does not necessarily occur. However, binder ductility shows drastic and consistent reduction throughout the layer as aging increases. Analysis of internal structure using a CT scan revealed that there is also a lack of homogeneity in the air void and particle size distributions. Finally, this study suggests that full-depth PAM viscoelastic behavior is sensitive to saturation level, and this is a relevant subject to be considered, since partial saturation may be a condition often observed in the field.

Tailoring Microstructure and Mechanical Properties of Additively Manufactured Inconel 625 by Remelting Strategy in Laser Powder Bed Fusion

This study investigates the effect of laser power applied for a remelting scan in the laser powder bed fusion process on the formation of a bimodal microstructure and its impact on the mechanical properties of Ni-based Inconel 625 superalloy. Comparison of primary and remelting scans at similar surface energy densities revealed that the melt pools obtained in the remelting scan are smaller than in the primary scan. To achieve comparable remelted melt pool sizes, the 25 pct increase in energy is required. The shape and size of the remelted melt pools significantly affect the microstructure and material texture. The lower surface energy density in laser powder bed fusion favors the formation of a bimodal microstructure with large columnar grains and fine grain bands. Application of higher energy results in the formation of large columnar grains with Goss texture along build direction and separated by a large amount of low angle grain boundaries. Remelting scan also affects reduction of porosity and increasing of the area fraction of nanometric oxide inclusions. The study revealed that the samples subjected to a remelting laser scan and tensile tested along the direction of columnar grains exhibited higher ductility, which was associated with a slight decrease in the ultimate tensile strength compared to the samples that were not remelted. It was demonstrated that the remelting scan in the laser powder bed fusion process offers the possibility of improving the reliability of additively manufactured Inconel 625 superalloy by reducing porosity and tailoring its microstructure towards single-crystal-like, and thus improving the mechanical properties.Graphical

Virtual design of woven fabrics based on parametric modeling and physically based rendering

Textures of woven fabrics are usually designed and produced according to geometric laws in the 2D plane. Physically Based Rendering (PBR) can further optimize and enrich the texture effect, but its application to the more complex 3D structures has been limited. This work reports a method that uses PBR and parametric modeling to construct woven textured materials with centimeter and millimeter level 3D structures. The method can design the structures of various woven fabrics without the need for analyzing the fabric structure details and transfer the inherently iterative work of fabric design to the digital space. The design can be directly applied to mainstream 3D modeling software for virtual presentations in different applications, hence improving the efficiency of woven fabric design and the fidelity of virtual presentation of fabric materials.

Applications of the Clifford torus to material textures

This paper introduces a new 2D representation of the orientation distribution function for an arbitrary material texture. The approach is based on the isometric square torus mapping of the Clifford torus, which allows for points on the unit quaternion hypersphere (each corresponding to a 3D orientation) to be represented in a periodic 2D square map. The combination of three such orthogonal mappings into a single RGB (red–green–blue) image provides a compact periodic representation of any set of orientations. Square torus representations of five different orientation sampling methods are compared and analyzed in terms of the Riesz s energies that quantify the uniformity of the samplings. The effect of crystallographic symmetry on the square torus map is analyzed in terms of the Rodrigues fundamental zones for the rotational symmetry groups. The paper concludes with example representations of important texture components in cubic and hexagonal materials. The new RGB representation provides a convenient and compact way of generating training data for the automated analysis of material textures by means of neural networks.

Enhancement of Surface Properties Using Ultrashort-Pulsed-Laser Texturing: A Review

Surface texturing, which has recently garnered increased attention, involves modifying the surface texture of materials to enhance their tribology. Various methods have been developed for surface texturing. Laser surface texturing (LST) has attracted considerable interest because of its excellent texturing accuracy, controllability, and flexibility. It improves surface wettability properties and increases the wear resistance of materials while reducing the coefficient of friction. Herein, we present an overview of the underlying mechanisms of interactions between short-pulsed lasers and materials. In addition, we review published studies on the effects of LST on surface properties, including surface roughness, wettability, friction, and wear resistance. We believe that this review will provide valuable insights into the recent advances in surface property enhancement through LST, which exhibits potential for various applications.

Textile aesthetics in mending

This article explores how designers in textiles and clothing can use their skills in materials and aesthetics to change perceptions of garments when they show signs of wear. Beyond prolonging clothing lifespan, garment repair can serve as a bottom-up approach to alter clothing culture through innovative creativity. With this article, I substantiate the discussion of mending as an alternative avenue that can echo another aesthetic within the realm of fashion. A growing body of research is occupied with how garment repair can create resilience in the textile and clothing industry by influencing the use phase. This has given rise to studies on garment design from a ‘repair thinking’ perspective, where mending is integrated into the design phase, prompting innovative approaches to garment construction, product types, and business models to rebalance the fashion industry. However, extending garment life through mending is complex, influenced by systemic and social factors, often overshadowed by the polished image of fashion. Within this scope, aesthetic and material expressions of mending are still to be researched. Designers possess skills in working with aesthetics, such as material qualities, visual expressions, textures, colours and patterns. This article explores how these skills illuminate the socio-material dimensions of garment mending. The research includes three encounters with mending which has resulted in a range of full-garment samples and insights into related material processes. The preliminary findings are visualized in a spectrum of mending concepts. Drawing from this overview of material expressions, the article discusses the role of designers in a world undergoing sustainable climate transformation. It presents three case examples showcasing how textile and clothing designers can employ their skills in materials and aesthetics. The article concludes by considering how future research could involve collaboration with companies to introduce mending concepts as part of a broader appreciation of material expression.

Analytical Model of Quantitative Texture Prediction Considering Heat Transfer Based on Single-Phase Material in Laser Powder Bed Fusion

Laser powder bed fusion (LPBF) is widely used in metal additive manufacturing to create geometrically complex parts, where heat transfer and its affected temperature distribution significantly influence the parts’ materials’ microstructure and the resulting materials’ properties. Among all the microstructure representations, crystallographic orientations play a paramount role in determining the mechanical properties of materials. This paper first developed a physics-based analytical model to predict the 3D temperature distribution in PBF considering heat transfer boundary conditions; heat input using point-moving heat source solutions; and heat loss due to heat conduction, convection, and radiation. The superposition principle obtained temperature distributions based on linear heat sources and linear heat loss solutions. Then, the temperature distribution was used to analytically obtain the texture grown on a substrate with random grain orientations considering columnar-to-equiaxed transition (CET). Thus, the link between process parameters and texture was established through CET models and physical rules. Ti-6Al-4V was selected to demonstrate the capability of the analytical model in a single-phase situation. By applying advanced thermal models, the accuracy of the texture prediction was evaluated based on a comparison of experimental data from the literature and past analytical model results. Hence, this work not only provides a method of the fast analytical simulation of texture prediction in the single-phase mode for metallic materials but also paves the road for subsequent studies on microstructure-affected or texture-affected materials’ properties for both academic research and industrial applications. The prediction of single-phase material texture has never been achieved before, and the scalability has been expanded.