Characterization Of Materials Research Articles

The Potential for Material Property Characterization Using Physics-Informed Neural Networks and Ultrasonic Wave Data

ABSTRACT There is a need for reliable nondestructive test methods that can collect data from structural members and analyze the results in a rapid and efficient manner. Large amounts of test data are needed to achieve such characterization, which provides additional challenges because of their heterogeneity and complexity. Advances in machine learning, in particular physics-informed neural networks (PINN), offer potential to address these problems. PINN is a particular form of artificial neural networks (ANN) and portends notable advantages over traditional measurand analysis or purely data-driven approaches. Here, we explore the potential of heterogeneous material property characterization using PINN and ultrasonic wave data. First, several types of 1-D ultrasonic wave data are numerically simulated for a spatially heterogeneous material, and then PINN is applied to predict wave velocity, defect location, and energy dissipation. Then, three different types of defects are simulated and all defects are detected using the corresponding 2-D ultrasonic wave data and PINN. The presented results demonstrate the promise of PINN to assist with heterogeneous material characterization methods.

Recycling of mineral wool waste as supplementary cementitious material through thermochemical treatment.

Mineral wool is commonly used in construction as thermal insulation material. After the product's lifetime, it is classified as hazardous waste if no trademark of the European Certification Board for Mineral Wool Products (EUCEB) or the German Institute for Quality Assurance and Labelling (RAL) exists. Mineral Wool Waste (MWW) is typically landfilled in Europe, which is challenging due to its low bulk density and dimensional stability. This circumstance highlights the need for alternative recycling methods that increase the recycling rate of construction and demolition (C&D) waste. This article outlines the recycling opportunities of MWW and focuses on the use of thermochemical treatment of different mixtures of input materials to produce a supplementary cementitious material (SCM). The material characterisation results and investigations on the binder suitability demonstrate that the slag fractions after the thermochemical treatment are well-qualified to be used as reactive binder components. Additionally, a material flow analysis was conducted to estimate the substitution potential of MWW as SCM in the Austrian cement industry.

Systematic evaluation of methods for iron-impregnation of biochar and effects on arsenic in flooded soils.

There is a need for innovative strategies to decrease the mobility of metal(loids) including arsenic (As) and cadmium (Cd) in agricultural soils, including rice paddies, so as to minimize dietary exposure to these toxic elements. Iron (Fe)-modified biochars (FBCs) are used to immobilize As and Cd in soil-water systems, but there is a lack of clarity on optimal methods for preparing FBCs because there are only limited studies that directly compare BCs impregnated with Fe under different conditions. There is also a lack of information on the long-term performance of FBCs in flooded soil environments, where reductive dissolution of Fe (oxy)hydroxide phases loaded onto biochar surfaces may decrease the effectiveness of FBCs. This study uses material characterization methods including FTIR, SEM-EDX, BET, and adsorption isotherm experiments to investigate the effects of Fe-impregnation methods (pH, pyrolysis sequence, and sonication) on the morphology and mineralogy of Fe loaded onto the biochar surface, and to FBC adsorbent properties for arsenate (As(V)), arsenite (As(III)), and Cd. Acidic impregnation conditions favored the adsorption of As(III) onto amorphous Fe phases that were evenly distributed on the biochar surface, including within the biochar pore structure. The combination of sonication with acidic Fe-impregnation conditions led to the best adsorption capacities for As(V) and As(III) (4830 and 11,166 μg As g-1 biochar, respectively). Alkaline Fe-impregnation conditions led to the highest Cd adsorption capacity of 3054 μg Cd g-1 biochar, but had poor effectiveness as an As adsorbent. Amending soil with 5% (w/w) of an acid-impregnated and sonicated FBC was more effective than an alkaline-impregnated FBC or ferrihydrite in decreasing porewater As concentrations. The acid-impregnated FBC also had greater longevity, decreasing As by 54% and 56% in two flooded phases, probably due to the greater stability of Fe(III) within the biochar pore structure that may have a direct chemical bond to the biochar surface. This study demonstrates that FBCs can be designed with selectivity towards different As species or Cd and that they can maintain their effectiveness under anaerobic soil conditions. This is the first study to systematically test how impregnation conditions affect the stability of FBCs in soils under multiple drying-rewetting cycles.

Dynamic behavior of twisted UHMWPE yarns

Twisting is an effective method to reduce defects during fabric weaving and improve the impact resistance of the armor material. This study examined the dynamic behavior of twisted ultra-high molecular weight polyethylene (UHMWPE) yarns. Material characterization was conducted using three-dimensional X-ray tomography and scanning electron microscopy (SEM). Dynamic mechanical experiments were carried out on the twisted yarns using a Kolsky bar, with the yarn's failure process captured in real time through high-speed imaging. Additionally, the digital imaging correlation (DIC) technique was used to calibrate the strain measured by the Kolsky bar. Post-fracture analysis was performed using SEM. The effects of twisting extent, strain rate, and gauge length on the dynamic behavior of twisted yarns were studied. It was observed that all twisted yarns underwent elongation, shrinkage, fiber breakage, untwisting, and yarn rupture. Furthermore, as the twisting degree and strain rate increased, and the gauge length decreased, the fracture area became more concentrated. The tensile strength peaked at a twisting degree of 250 t/m and decreased thereafter. Moreover, twisting was found to alter the sensitivity of the yarns' stress–strain curves and tensile properties to the strain rate and gauge length.

Machine Learning for Analyses and Automation of Structural Characterization of Polymer Materials

Machine Learning for Analyses and Automation of Structural Characterization of Polymer Materials

Performance of sulfided NiMo catalyst supported on pillared bentonite Al and Ti under hydrodeoxygenation reaction of guaiacol

Bio-crude oil is known to be sustainable, eco-environmentally, and an alternative energy source produced by biomass pyrolysis. However, its quality remains relatively low due to a higher oxygen concentration compared to liquid fuels from fossils. Therefore, an upgrading process is necessary through the catalytic hydrodeoxygenation (HDO) process. This work synthesized pillared bentonite using Al and Ti metals as the pillaring agent to produce Al-PILC and Ti-PILC as catalyst support for sulfided NiMo. Their catalytic activity in HDO reaction using guaiacol as a model compound of bio-crude oil were also evaluated. Characterization of the bentonite-pillared materials, including Al-PILC, Mo/Al-PILC, NiMo/Al-PILC, Ti-PILC, Mo/Ti-PILC, and NiMo/Ti-PILC, was performed using Surface Area Analyzer, X-ray Diffractometer (XRD), Temperature-Programmed Desorption of ammonia (NH3-TPD), X-Ray Fluorescence (XRF), and Scanning Electron Microscope (SEM) techniques. The characterization results confirm the pillarization process of bentonite using Al and Ti metals as the pillaring agent, and the preparation of the NiMo catalyst using the stepwise impregnation method was successfully prepared. The NiMo/Ti-PILC catalyst performs a superior conversion value on the HDO guaiacol reaction than other catalysts. A well dispersion of Mo and Ni metals on the surface support (NiMo/Ti-PILC), thus creating numerous active sites of the catalyst after the sulfidation. Variations in time and temperature during the HDO guaiacol reaction significantly affected the conversion.

Study on physico‑mechanical characterization of rock-like material with bedding planes under coupled static and dynamic cyclic loadings

Study on physico‑mechanical characterization of rock-like material with bedding planes under coupled static and dynamic cyclic loadings

Preparation and characterization of cellulose fluorescent material: Experiment and simulation

Preparation and characterization of cellulose fluorescent material: Experiment and simulation

Structure and morphology of chars and activated carbons obtained from thermal treatment of coal and biomass origin materials, including their wastes: Results from the ICCP Microscopy of Carbon Materials Working Group

This paper describes the evaluation of petrographic textures in char and activated carbon derived from coal, coal by-products and biomass, formed during carbonization and activation processes. This work represents the results of interlaboratory exercises from 2016 to 2022 of the Microscopy of Carbon Materials Working Group in Commission III of the International Committee for Coal and Organic Petrology. The interlaboratory exercises were run on photomicrograph samples. For textural characterization of carbon materials, the existing American Society for Testing and Materials (ASTM) classification system for metallurgical coke was applied. Morphological differences were evaluated in 29 carbon material types, including 22 char samples, and 7 activated carbon (AC) samples obtained experimentally using conventional direct/indirect and microwave heating technologies. This approach gives an extended view on the identification of microporous carbons, and how a certain heat treatment develops a certain optical texture and structure in a raw material. The requested evaluation of carbon materials was related to their porosity, origin, extent, and characteristics, which are particular to each carbon material type. Because carbon matrices can form a wide range of optical textures during heat treatment it is important to demonstrate which carbon occurrences will have a crucial role in industrial applications dominated by adsorption phenomena.The interlaboratory exercises included 17 participants from 14 laboratories. Four sets of digital black and white and colour photomicrographs were distributed, which in total comprised 184 fields of different types of carbon material. The results were evaluated based on four levels: (i) optical texture (isotropic/anisotropic), (ii) optical type and size (punctiform, mosaic, fiber, ribbon, domain), iii) morphology (porous, non-porous/massive), and (iv) particle origin (precursor type).The statistical method applied to evaluate the results was based on “raw agreement indices”. Comparative analyses of the average values of the level of overall agreement showed homogeneity in the results, the mean value was 89%, with a minimum value of 87% and a maximum value of 91% for those who participated in at least three out of four exercises.

Comprehensive characterization of modern industrial Argentinian paints for improved chronological painting attribution

Throughout the twentieth century, the paint industry developed a multitude of new binding media, pigments and additives that improved the appearance, ease of application, and performance of modern industrial paints. Depending on when and where they were first manufactured, and when they were introduced into paint formulations, some of these new paint components could conceivably be chronological markers useful in assigning attribution to specific artists or in the study of forgeries. The aim of this study was to develop a systematic methodology for characterizing organic and inorganic materials in modern paints, and search for potential chronological markers. Colored reference paints manufactured by local companies in Argentina from the 1940s and 1950s were studied with a multi-analytical approach that included Fourier-transform infrared spectroscopy, gas chromatography coupled with mass spectrometry, Raman spectroscopy, X-ray diffraction, X-ray fluorescence and scanning electron microscopy with energy dispersive X-ray analysis. A wide range of compounds was identified due to the complementarity use of the analytical techniques. Historical references, patents, books, and scientific publications about the materials used in that time period provided invaluable information in establishing tentative timelines for modern paint components. This investigation was part of a broader interdisciplinary investigation of Concrete Art, an international art movement of the beginning of the twentieth century, which took place in Argentina and other nearby countries during the 1940s and 1950s. To prove the concept, a micro-sample from “Obra N° 171” by Raúl Lozza was analyzed. Organic and inorganic fractions were studied and the information collected was correlated with developed timelines to support the authentication process. Ultimately, the information from this study may also have a direct impact on the key areas of material characterization, aging behavior, and conservation of works of art made from these products.

Formation mechanism and improved remedy of thermal property of cold shut surface defects in Vortex Flow Meters: Numerical simulation and experimental verification in investment casting of 316 L stainless steel

The purpose of this study aims to investigate the leading causes of CS (Cold Shut) defects in VFM (Vortex Flow Meters) of intricate geometric configuration and propose improvement strategies to leverage the thermal property in the vicinity of thin-walled regions, such as insulation-enhanced uniformly distributed temperature via ceramic core embedment. First, penetrant testing reveals whether the defect is a penetrating-type defect. Second, several extensive material characterization techniques such as optical microscopy (OM), energy-dispersive X-ray spectroscopy (EDS) analysis, and charge-coupled device (CCD) were employed to provide deeper insights into the formation and morphology of defects. Third, numerical simulations and experimental verifications were utilized to further analyze the causes of CS defects in vortex flowmeters. Fourth, effective preventive measures were designed after identifying the causes of defects, which involved using ceramic cores to replace the shell at deep and thin-walled locations. A virtual thermo-dynamic sensor (VTDS) was used to analyze the temperature distribution in the area before and after the installation of ceramic cores. The results indicate that the temperature in the defect area increased by >40 degrees during the filling period from 2.5 s to 5 s. Additionally, adequate thermal uniformity was achieved through the high thermal conductivity of the ceramic material, thereby reducing the cooling rate and the coefficient of kinematic viscosity in that area, leading to improved fluidity of the molten iron. Ultimately, the occurrence rate of CS defects decreased from 42.6 % to 0 %.

XPS Study on the determination of binding energies in high-purity TiO2 nanoparticles

This study focuses on the precise determination of the binding energies of high-purity TiO2 nano-particles, using X-ray photoelectron spectroscopy (XPS). TiO2, an essential ceramic in high-tech sectors such as electronics, aerospace and photocatalysis, was analyzed in its pure state (99.5%) directly as received from the supplier, without previous alterations. XPS spectra revealed typical bond energy peaks for Ti at 458.42 eV and 464.13 eV, corresponding to Ti2p3/2 and Ti2p1/2 levels respectively, with a difference of 5.71 eV, validating the expected electron structure for Ti in TiO2. Additionally, peaks were identified at 457.36 eV and 463.36 eV, attributable to Ti3+, present in a Ti3O5 phase, as confirmed by X-ray diffraction (XRD) analysis. The mid-height width (FWHM) of the main Ti4+ peaks, ranging from 1.08 to 1.87 eV, and 0.96 eV for the Ti3+ peaks, highlights the homogeneity and exceptional purity of the sample. These findings not only corroborate the high quality of TiO2, but also provide a crucial benchmark for the scientific community, facilitating de-tailed comparisons with other samples and encouraging the development of innovative processes and materials. This study underscores the value of the XPS technique in the characterization of advanced ceramic materials and sets a standard for future research.

A review of Microstructural Characterization and Liquid Transport in Porous Materials Through Image Processing Techniques

A review of Microstructural Characterization and Liquid Transport in Porous Materials Through Image Processing Techniques

Nanoscale Three-Dimensional Imaging of Integrated Circuits Using a Scanning Electron Microscope and Transition-Edge Sensor Spectrometer

X-ray nanotomography is a powerful tool for the characterization of nanoscale materials and structures, but it is difficult to implement due to the competing requirements of X-ray flux and spot size. Due to this constraint, state-of-the-art nanotomography is predominantly performed at large synchrotron facilities. We present a laboratory-scale nanotomography instrument that achieves nanoscale spatial resolution while addressing the limitations of conventional tomography tools. The instrument combines the electron beam of a scanning electron microscope (SEM) with the precise, broadband X-ray detection of a superconducting transition-edge sensor (TES) microcalorimeter. The electron beam generates a highly focused X-ray spot on a metal target held micrometers away from the sample of interest, while the TES spectrometer isolates target photons with a high signal-to-noise ratio. This combination of a focused X-ray spot, energy-resolved X-ray detection, and unique system geometry enables nanoscale, element-specific X-ray imaging in a compact footprint. The proof of concept for this approach to X-ray nanotomography is demonstrated by imaging 160 nm features in three dimensions in six layers of a Cu-SiO2 integrated circuit, and a path toward finer resolution and enhanced imaging capabilities is discussed.

Determination of binding energies in high purity 2H graphite using XPS

This study focuses on the detailed characterization of graphite, employing techniques such as X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS). Graphite, a crucial material for engineering applications and advanced technologies, was analyzed in its pure state as provided by the manufacturer, without any pretreatment. XPS analysis revealed a spectrum dominated by carbon, with binding energies confirming the expected electronic structure and the presence of surface functional groups, including oxygen, silicon, and phosphorus. Although these impurities were identified, they do not appear to have affected the binding energies of the primary carbon, suggesting that their influence is confined to the surface properties and does not extend to the internal electronic structure of the graphite. XRD corroborated the high structural purity and detected a secondary SiP2O7 phase in minimal quantities. These findings validate the high quality of the graphite and provide critical information for the scientific community, establishing a benchmark for comparisons in future studies and developments of materials. This work underscores the value of combining XPS, XRD, and SEM-EDS for the thorough characterization of carbon-based materials.

Technology Selection for Inline Topography Measurement with Rover-Borne Laser Spectrometers

This work studies enhancing the capabilities of compact laser spectroscopes integrated into space-exploration rovers by adding 3D topography measurement techniques. Laser spectroscopy enables the in situ analysis of sample composition, aiding in the understanding of the geological history of extraterrestrial bodies. To complement spectroscopic data, the inclusion of 3D imaging is proposed to provide unprecedented contextual information. The morphological information aids material characterization and hence the constraining of rock and mineral histories. Assigning height information to lateral pixels creates topographies, which offer a more complete spatial dataset than contextual 2D imaging. To aid the integration of 3D measurement into future proposals for rover-based laser spectrometers, the relevant scientific, rover, and sample constraints are outlined. The candidate 3D technologies are discussed, and estimates of performance, weight, and power consumptions guide the down-selection process in three application examples. Technology choice is discussed from different perspectives. Inline microscopic fringe-projection profilometry, incoherent digital holography, and multiwavelength digital holography are found to be promising candidates for further development.

Aluminum scandium nitride on 8-inch Si wafers: material characterization and photonic device demonstration

The anisotropic optical properties of aluminum scandium nitride (Al1−xSc x N) thin films for both ordinary and extraordinary light are investigated. A quantitative analysis of the band structures of the wurtzite Al1−xSc x N is carried out. In addition, Al1−xSc x N photonic waveguides and bends are fabricated on 8-inch Si substrates. With x = 0.087 and 0.181, the light propagation losses are 5.98 ± 0.11 dB/cm and 8.23 ± 0.39 dB/cm, and the 90° bending losses are 0.05 dB/turn and 0.08 dB/turn at 1550 nm wavelength, respectively.

Mesoscale numerical modeling of unreinforced masonry wall response to underground dynamic loads: A comparative study utilizing FEM and DEM

This study investigates the response of unreinforced masonry walls to dynamic loading induced by underground explosions. A mesoscale numerical modeling approach is employed to capture the nonlinear behavior of the masonry wall. The Menetrey-Willam yield criterion is utilized to represent the wall's nonlinear behavior at the mesoscale level, while the cohesive zone model (CZM) is employed to simulate the behavior of mortar, thereby overcoming the limitations of linear elasticity. The soil is characterized using the modified Mohr-Coulomb model. After calibration against material characterization tests, a numerical model is developed to obtain results that closely match experimental data. Given the disturbed nature of the crater soil, both finite element and discrete element methods are utilized for soil modeling. Comparison between these methods reveals that the discrete element method yields more realistic results in terms of displacement and strain. The study's findings enhance our understanding of the response of unreinforced masonry walls to dynamic loading and offer valuable insights for future structural designs and safety assessments.

Mechanochemical Cyclotrimerization: A Versatile Tool to Covalent Organic Frameworks with Tunable Stacking Mode.

We introduce the first mechanochemical cyclotrimerization of nitriles, a facile strategy for synthesizing triazine-containing molecules and materials, overcoming challenges related to carbonization and solubility. Conducting this solid-state approach in a mixer ball mill with 4-Methylbenzonitrile, we synthesize Tris(4-methylphenyl)-1,3,5-triazine quantitatively in as little as 90 minutes. Just as fast, this mechanochemical method facilitates the synthesis of the covalent triazine framework CTF-1 using 1,4 Dicyanobenzene. Material characterization confirms its porous (650m²g-1) and crystalline nature. Adjusting the induced mechanical energy allows control over the obtained stacking conformation of the resulting CTFs - from a staggered AB arrangement to an eclipsed AA stacking conformation. Finally, a substrate scope demonstrates the versatility of this approach, successfully yielding various CTFs.

Mechanochemical Cyclotrimerization: A Versatile Tool to Covalent Organic Frameworks with Tunable Stacking Mode

We introduce the first mechanochemical cyclotrimerization of nitriles, a facile strategy for synthesizing triazine‐containing molecules and materials, overcoming challenges related to carbonization and solubility. Conducting this solid‐state approach in a mixer ball mill with 4‐Methylbenzonitrile, we synthesize Tris(4‐methylphenyl)‐1,3,5‐triazine quantitatively in as little as 90 minutes. Just as fast, this mechanochemical method facilitates the synthesis of the covalent triazine framework CTF‐1 using 1,4 Dicyanobenzene. Material characterization confirms its porous (650m²g‐1) and crystalline nature. Adjusting the induced mechanical energy allows control over the obtained stacking conformation of the resulting CTFs ‐ from a staggered AB arrangement to an eclipsed AA stacking conformation. Finally, a substrate scope demonstrates the versatility of this approach, successfully yielding various CTFs.