Materials Characterization

This study systematically investigates the effect of different heat-treatment conditions on the microstructure, mechanical properties, hot corrosion behaviour, and surface topography of Inconel 718. The solution-treated alloy exhibited reduced hardness compared with aged conditions due to dissolution of γ ′ /γ ′′ precipitates, whereas dual aging significantly enhanced precipitation strengthening. Despite this, ST718 demonstrated superior corrosion resistance, indicating that hardness and corrosion performance are not directly correlated. SEM analysis revealed improved elemental homogenisation at higher solutionizing temperatures, with ST718 and PH718 retaining columnar grains, while DA718 and the untreated alloy exhibited equiaxed structures. XRD analysis confirmed the γ matrix as the dominant phase along with δ-phase and stable carbides. Modified hot-corrosion testing at 1000 and 1100 °C revealed temperaturedependent mass change behaviour, with solution-treated specimens demonstrating comparatively improved oxide-scale stability. AFM analysis indicated substantial increases in surface roughness at elevated temperature, particularly for the dual-aged condition. The results establish a direct correlation between heat-treatment-induced phase evolution and hightemperature performance.

A waveguide-based retrieval method for measuring complex permittivity and permeability tensors of metamaterials is presented. In the proposed scheme, multiple independent sets of scattering data for the material under test with different orientations are measured in the frequency range corresponding to the dominant TE 10 mode. The method is applied to various metamaterials and shows its effectiveness in the effective parameters extraction.

In this study, we have discussed the process of manufacturing natural fiber reinforced composites (NFRCs) using hand lay-up method, which is one of the most used methods due to its ease of operation, low cost and applicability in small scale industries. The process of mold preparation, fiber layering, resin application, curing, and finishing is described with focus on the ability to tailor the properties of the composite material. Comparative mechanical and thermal properties of natural fibers like jute, flax, coir, and hemp are also studied. The review also discusses the tensile strength, flexural strength, impact strength, and thermal stability of NFRCs depending on the type of fiber, fiber orientation, and fiber surface treatment. Some of the issues like poor fiber-matrix interface, porosity and voids are described and ways to overcome them like alkali treatment and vacuum assisted methods are also described. The use of NFRCs in automotive, construction, and packaging industries are discussed to show how they are lighter, stronger, and more environmentally friendly than synthetic composites. The future research areas include the development of hybrid composites, biodegradable resin systems, and manufacturing technologies to enhance the NFRCs for industrial applications. This review also highlights the possibility of NFRCs achieving sustainability and functionality in one package, which can provide practical solutions to the reduction of environmental footprint while addressing the various needs of industries.

The hand layup approach was used to fabricate epoxy-based hybrid
polymer composites reinforced with biochar made from recycled
rice husk and basalt fibers. The biochar, derived from recycled rice
husk, served as a filler material to enhance the composite properties.
E1 (0% biochar), E2 (2% biochar), E3 (5% biochar), and E4 (7%
biochar), where the four samples with varied biochar percentage
were made.The tensile strength increased from 45.2 MPa (E1) to
58.7 MPa (E3) in mechanical tests, demonstrating improved performance
with a higher biochar content. Flexural strength peaked in
E3 at 85.3 MPa, however filler agglomeration caused a minor drop
in E4. Energy Dispersive Spectroscopy (EDS) and Field Emission
Scanning Electron Microscopy was utilized to examine the surface
morphology and dispersion of biochar within the composite matrix
to assist in determining the elemental composition of the composites
and their morphological properties.The compatibility of biochar
with the polymer matrix was demonstrated by FTIR
spectroscopy, which validated chemical interactions.These results
highlight biochar’s potential as a sustainable filler material to
improve environmental and mechanical performance. Strength
and durability were balanced at the ideal biochar level of 5%,
providing a route for the creation of high-performance, environmentally
friendly composites appropriate for cutting-edge technical
applications.

Abstract
Green synthesis is now becoming and financially and economically beneficial and
have no effects on environmental effects like synthesis of NP’s from other chemical
methods green synthesis include synthesis of NP’s from plants fruits and leafs, plants
root and flowers, from fungi, starch, from honey, from algae and from bacteria.
Synthesized NP’s from green method are biocompatible and have application in
medial field and many more. We synthesized Mn metal oxide Nano-materials utilizing
lemon extract as a reducing agent. XRD, UV and FTIR Spectroscopic techniques was
used to characterize. Techniques were used to assess the Nano-forms morphology
and structure. While manganese NPs (MNPs) generated are spherical but varied in
size by 50 nm and 40-60 carometers, respectively. Manganese nanoparticles are also
have application in many fields like energy production, as catalyst, purification of DNA
and have properties like optical and magnetic properties. Future of NP’s from green
method and especially Mn NP’s is bright in many fields.

When a slowly variable magnetic field ( Hz) is applied through a yoke on a ferromagnetic material, discontinuous changes on the magnetic flow density are produced. This phenomenon, called Magnetic Barkhausen Noise (MBN), obeys the movement of magnetic domain walls and its frequency range is about [10-100] kHz. It involves sudden magnetization changes and localized variations of mechanical stresses which originate elastic waves known as Magneto Acoustic Emission (MAE) on the frequency range of 20 kHz up to 1 MHz. Both, MBN and MAE depend on the material microstructural characteristics and they may be considered as non-destructive evaluation techniques. This work is based on MBN and MAE tests carried out on 5 groups of different stainless steel specimens (AISI 409, AISI 430, AISI 439, AISI 441A and AISI 444), for two applied magnetic fields, parallel and perpendicular to the rolling direction.

Wearable and portable devices are gaining significant popularity across consumer electronics as well as in medical and industrial fields. To ensure that these devices are both comfortable and appealing to users, they need to have low battery consumption and be compact in both size and weight. The EGluco project is focused on developing a wearable device for noninvasive blood glucose monitoring. This multi-sensor device incorporates electrical bioimpedance spectroscopy as one of its measurement techniques. One of the earlier versions of the device was deemed unsuitable as a wearable due to its large size and high power consumption. To make the device more suitable for wearability, the previous hardware was assessed, and a new design was proposed that simplified the system's power supply and reduced the operating voltage. This article presents two of these designs: an improved Howland current source with a supply voltage of 3.3 V , an output current of 250 µA, and the ability to conduct bioimpedance analysis up to 1 MHz using pulsed DIBS (Discrete Interval Binary Sequence) signals, and an instrumentation amplifier with the same supply voltage as the current source, a voltage gain of four, and a slew rate of 150 V /µs. By simplifying the power supply and implementing other changes, the device's size was reduced to a single 5 × 5 cm circuit board, compared to the previous configuration of four separate boards connected by cables.

A series of six lead-bismuth tellurite glass samples were prepared by using the melt quenching technique. The Physical properties of the samples such as density and molar were studied. The measurements of density were calculated via using Archimedes' principle. XDR technique was used to confirm the amorphous nature of the samples. The optical properties of the samples such as direct and indirect bandgaps were calculated based on the Davis-Mott equation by employing Tauc's method. The disorderliness of the glass system was measured by calculating Urbach energy and steepness. Density and refractive indices results show an increasing trend with increasing PbO concentration. The non-metallic nature of the samples was investigated by using the metallization criterion. Optical basicity and basicity moderating parameters were calculated for each glass sample by using Duffy and Ingram formula. The metallization criterion results of the synthesized glasses are best for nonlinear optical devices.

Texture modification during sheet rolling appears differently in binary Mg-RE (rare-earth) or Mg-Ca alloy, compared to their ternary counterparts containing Zn. The differences in texture development and the active deformation mechanisms under tensile loading were investigated in the binary alloys. These analyses are based on in-situ synchrotron experiments and electron backscatter diffraction measurements to reveal direct experimental evidence of the texture development and the active deformation mechanisms. Higher activations of nonbasal <a> and pyramidal <c+a> dislocations were found in the Nd or Ca containing Mg alloys, compared to the Mg-Zn alloy. The texture development shows an obvious feature, which is a broadening of the basal pole intensity distribution perpendicular to the loading direction and a strengthening of the <1010> pole at the loading direction in all examined sheets. This texture development relates to the higher activation of prismatic <a> slip. The addition of Zn in the Mg-RE or Mg-Ca alloys further promotes the activation of nonbasal <a> and pyramidal <c+a> dislocations. This enhanced prismatic <a> slip in the Zn containing ternary alloys is confirmed by EBSD misorientation analysis.

Experiments were conducted for the study of the evolution of the microstructure in a nanocrystalline CoCrFeNi multi-principal element alloy during annealing. The nanocrystalline state was achieved by high-pressure torsion (HPT) which is a well-defined severe plastic deformation technique. The heat treatment of the nanocrystalline CoCrFeNi alloy was performed in a differential scanning calorimeter (DSC). It was found that the thermogram contains two exothermic peaks with maxima at about 680 and 870 K. For further analysis, a different set of the samples were annealed to temperatures below and above the two DSC peaks. It was revealed the first exothermic peak was related to the decrease of the density of lattice defects (dislocations and twin faults) while the grain size remained consistent. The comparison of the measured and the calculated released heat values suggested that during this recovery a high concentration of excess vacancies was annihilated (about 10−3). The second exother...

Dilatometry tests were performed to study the phase transformation kinetic of nuclear fuel claddings made of Zircaloy-4 upon fast heating rates (up to 2000 • C/s). These tests highlighted that from equilibrium to 500 • C/s the temperature at which the transformation starts shifts towards higher temperatures with increasing heating rates. Above 500 • C/s no impact of the heating rate was observed. The temperature at which the transformation ends remains close to 960 • C with no clear dependence on heating rate. Metallurgical analyses were carried out and were in agreement with the results obtained by dilatometry. A phase transition model was identified from equilibrium to 2000 • C/s.

In this work, the wear behavior, hardness, and microstructure of brass matrix surface composites (BMSCs) are produced by friction stir processing techniques with different traverse speeds varying between 23 to 57 mm/min. The tungsten particle (W) with a volume fraction of 9 % and rotational speed of 1000 rpm are considered as other constant process parameter. Microstructural analysis revealed no W particle clustering in the stir zone, with the lowest speed of 23 mm/min showing refined grains. The hardness decreased as traverse speed increased, reaching 165 Hv at 23 mm/min and 142 Hv at 57 mm/min, due to improved particle distribution, higher dislocation density, and refined grains at lower speeds. Similarly, wear rate decreased from 306 × 10⁻⁵ mm³/m at 57 mm/min to 239 × 10⁻⁵ mm³/m at 23 mm/min, while the coefficient of friction dropped from 0.62 to 0.36. Wear mechanisms varied with speed: adhesion and micro-cutting dominated at 57 mm/min, whereas adhesive wear was prevalent at 23 mm/min, along with smaller wear debris sizes at lower speeds.

Metallic bilayers and multi-layers have been recently utilized to achieve a wide range of mechanical, physical, and thermal properties. Among them, aluminum/stainless steel bilayer sheets have found increasing applications in the automotive and food industries due to their enhanced corrosion and wear resistance and low weight. The mechanical properties of Al1050/SS304 bilayer sheet prepared by cold rolling process were experimentally investigated in this research. The experiment was first designed considering three parameters of Al layer thickness, SS layer thickness, and their respective reduction ratio (𝑟) at three levels using Box-Benken design of experiment method. The bilayer sheet was made using the roll bonding method. The mechanical properties such as yield strength, ultimate strength, and elongation percentage were determined by the tensile test at various reduction ratios and thicknesses. Then, the response parameters were optimized individually and simultaneously. The variables were modeled by the response surface method to assess the effect of the input parameters of the process on the variation of the responses and analysis of variance, presentation of the regression equations of the output parameters, analysis of the RSM curves, effect interaction curves of the input parameters. Based on the results, in the RSM, the thickness of the Al layer had the highest impact on the yield strength and ultimate strength. Its effect was in inverse manner. The lowest influence was for the effect of the reduction ratio on the ultimate strength of the bilayer sheet. Optimizing three response parameters (yield and ultimate strengths, and elongation), these parameters reached their highest values for 𝑡 𝐴𝑙 = 2𝑚𝑚, 𝑡 𝑆𝑆 = 1.5𝑚𝑚, and r=61% which resulted in the yield strength, ultimate strength, and elongation values of 227 MPa, 534 MPa, and 26.9%, respectively.

As a part of a major study on 19th century Roman cements a laboratory optimisation study of the calcination of two marls has been conducted within the temperature range 730 to 1100 °C. Strength assessment has shown that the optimum kiln conditions lie towards lower temperatures and differ for the two marls by no more than some 50 °C. This paper discusses the clinker properties in terms of phase composition and microstructural features. The textural and mineralogical characteristics of the marl fractions significantly influence the nature and amount of phases formed during solid-state reactions under non-equilibrium conditions. At low to intermediate calcination temperatures it is mainly the fine-grained matrix of the marls which reacts, while coarse particles remain largely un-reacted. The major reactive crystalline phases identified in the optimum cements are belite in two polymorphs and free lime, while a number of other compounds remain unclear because of their non-crystalline nature.

The harmful effect of nickel ions released from conventional stainless steel implants has provided a high level of motivation for the further development of nickel-free stainless steels. In this paper, the microstructure of medical-grade nickel-free stainless steel powders, with the chemical composition of ASTM F2581, is studied during mechanical alloying and subsequent annealing. Rietveld X-ray diffraction and transmission electron microscopy evaluations reflect nanocrystallization, austenitization and amorphization of the powders due to mechanical activation. It is also realized that annealing of the as-milled powder can develop a single austenitic structure with nanometric crystallite sizes, implying a considerable inherent resistance to grain growth. This study demonstrates the merit of mechanical alloying and subsequent annealing in the development of nanostructured medical-grade stainless steels.

In the recent years, the addition of nitrogen to iron alloys by mechanical alloying has attracted considerable attention. In this paper, mechanical alloying of Fe-18Cr-8Mn powder mixture under a nitrogen atmosphere is considered from the viewpoints of nitrogen supersaturation and phase transformation. By progression of milling, austenitization and amorphization transformations are detected. The contribution of interstitial sites of the nanocrystalline phases to the nitrogen supersaturation is estimated by X-ray diffraction experiments. It is found that the contribution is progressively decreased by increasing the total nitrogen content. Typically, only about 4 percent of total incorporated nitrogen is distributed among the crystal interstitial sites of the Fe-18Cr-8Mn-2.5N alloy.

This paper investigates the effect of CaO on the structural, optical, thermal and photoluminescence properties of vanadate glasses with the composition V 2-x Ca x O 5-δ (x = 0.15, 0.20, 0.25, 0.30) for optoelectronics applications. The density, molar volume, polaron radius, and fragility index increase with increasing CaO doping into V 2 O 5. Structural characteristics studied through powder X-ray diffraction (PXRD) and Fourier transform infrared spectroscopy. The indirect and direct band gap energies are found to increase from 3.58 to 3.69 eV and from 4.12 to 4.22 eV with an increase in CaO concentration, respectively. It is observed that T g increases from 293 to 310 • C with increasing CaO content at the cost of V 2 O 5. The CIE chromaticity coordinates confirmed the greenish-blue emission in the prepared vanadate glass samples. The correlated colour temperature (CCT) is found in the range of 5305 to 18,029 K, confirming a daylight colour temperature. These findings highlight the multifunctional potential of CaO-doped vanadates for photonic, optical and emission display.

In this work, Mn-particulate Al/Cu multilayered (70Al/25Cu/5Mn) composites were fabricated by the accumulative roll bonding (ARB) process. Afterwards, the structure (after ARB and post-annealing) and failure (tensile fracture and corrosion in 3.5 wt% NaCl solution) studies were conducted on the specimens processed for different ARB cycles. Based on the results, no intermetallic compound was formed in the ARB-processed composites even to 9 cycles. Nonetheless, Al-Cu-(Mn) intermetallics were detected in the annealed samples, so that their amount was enhanced by increasing ARB cycle. Concerning the failure analyses, the resistance of the produced composites against corrosion and fracture, contrary to strength, was reduced by increasing ARB cycles.

Solution annealed and water quenched duplex and super duplex stainless steels are thermodynamically metastable systems at room temperature. These systems do not migrate spontaneously to a thermodynamically stable condition because an energy barrier separates the metastable and stable states. However, any heat input they receive, for example through isothermal treatment or through prolonged exposure to a voltaic arc in the welding process, cause them to reach a condition of stable equilibrium which, for super duplex stainless steels, means precipitation of intermetallic and carbide phases. These phases include the sigma phase, which is easily identified from its morphology, and its influence on the material's impact strength. The purpose of this work was to ascertain how 2-hour isothermal heat treatments at 920 °C and 980 °C affect the microstructure of ASTM A890/A890M GR 6A super duplex stainless steel. The sigma phase morphologies were found to be influenced by these two aging temperatures, with the material showing a predominantly lacy microstructure when heat treated at 920 °C and block-shaped when heat treated at 980 °C.

The production of massive duplex stainless steel castings weighting over 2 t, with thicknesses exceeding 5 in. represents a major challenge for the foundry industry. The difficulty in manufacturing such castings lies in the fact that thick sections experiment low cooling rates during the solidification process and during the solution annealing and water quenching heat treatment. As a result, intermetallic phases such as sigma phase (σ), Chi phase (χ), G phase, R phase, and complex carbides may precipitate, causing the material to be extremely brittle [Martins M, Casteletti LC. Effect of heat treatment on the mechanical properties of ASTM A890 grade 6A super duplex stainless steel. J ASTM Int 2005;2(1) [January]. ]. After solution annealing and water quenching, the steel is, in principle, free of intermetallic precipitates, but will contain residual stresses resulting from rapid cooling on quenching. During and after machining, these stresses may produce dimensional distortions in the casting, which can be avoided or at least reduced with stress relief heat treatments at intermediary temperatures, taking care to prevent the loss of mechanical properties, mainly impact toughness. The purpose of this study was to investigate the behavior of CD4MCu and CD4MCuN duplex stainless steels in impact tests under the conditions of solution annealing and water quenching and stress relief at 350 °C for 4 h and at 550 °C for 2 h. Compared to CD4MCu the high nitrogen content of CD4MCuN stainless steel has a more balanced microstructure with similar ferrite and austenite contents, providing it with higher energy-absorbing capacity in impact tests. CD4MCuN fracture surfaces have predominantly fibrous structures typical of high toughness materials, while the CD4MCu steel's fracture surface shows cleavage facets typical of low toughness materials. The stress relief heat treatments reduced the impact toughness of the CD4MCu alloy but did not affect the CD4MCuN alloy.

This study aims to identify the composition and crystalline structure of an unknown material later identi ed a Perovskite composition. The characterization techniques used include X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The research also discusses the critical steps involved in sample preparation, instrument operation, and optimization of experimental parameters. The comprehensive analysis will provide a better understanding of the material's properties, leading to its precise identi cation and potential classi cation within known material categories.

The microstructure and mechanical behavior during 100 • C warm rolling of the high-Zncontent Al 80 Zn 14 Li 2 Mg 2 Cu 2 alloy were investigated. The alloy plate was warm-rolled to reductions of 40%, 60%, and 80%. Hardness and tensile strength decreased continuously with increased rolling up to 60%, demonstrating work softening, followed by a slight increase at 80% reduction, indicating work hardening. Systematic characterization revealed that this non-monotonic mechanical response arises from a competition between particlestimulated nucleation (PSN)-assisted recrystallization and dislocation-driven hardening. The multi-scale intermetallic particles in this alloy play a dual role: coarse Al 5 CuLi 3 particles generate high-strain particle deformation zones (PDZs) that serve as potent PSN sites, while fine nano particles pin the recrystallized grain boundaries and restrict their growth. The unusually low PSN activation temperature is attributed to the synergistic effects of the high PDZ storage energy and the progressive subgrain rotation mechanism within the PDZ. The ability to control PSN via micro-and nano-scale intermetallics presents a viable pathway for achieving grain refinement in Al-based alloys and enhancing the machinability of high-Zn-content Al alloys.

Structural and optical properties of pure and Y-doped ZrO 2 nanopowders with different Y content sintered by co-precipitation of Zr and Y nitrates were investigated. It was observed that the increase of Y content stimulates the transformation of crystalline phase from monoclinic through tetragonal to cubic while the increase of calcinations time leads to the increase of ZrO 2 grain sizes. Generally, room temperature photo-and cathodoluminescence spectra showed several bands in blue-orange range. The increase of powder grains results in the enhancement of 2.81-eV photoluminescence caused probably by volume centers. Besides blueorange emission, additional "red" cathodoluminescence band was observed. Its intensity exceeds essentially the magnitude of other components and increases with cooling. This "red" band was found to be complex and caused by intradefect transition. The excitation mechanism of this band is discussed.

Ensuring the safe repurposing of X70 pipelines for hydrogen transport requires understanding how hydrogen interacts with deformation and local stress state. Two specimen geometries-a standard miniature tensile specimen and one with a hole at the gauge centre-are evaluated under in-situ electrochemical hydrogen charging. The effects of current density, pre-strain, and high stress triaxiality (η ≈ 0.48) are systematically examined. Increasing hydrogen flux reduces ductility sharply, whereas yield strength remains nearly unchanged. Pre-strained specimens exhibit higher embrittlement due to enhanced hydrogen trapping, and stressconcentrated specimens exhibit the most severe loss of plasticity and brittle fracture. Fractographic and crosssectional observations reveal hydrogen-assisted cracks at surface for higher hydrogen fugacity and a transition from ductile to quasi-cleavage fracture. Under similar saturated hydrogen concentration, these results demonstrate that hydrogen fugacity, plastic deformation, and local stress state act synergistically to control embrittlement severity in X70 pipeline steels exposed to hydrogen environment.

High-precision, low-noise transport measurements are essential for advancing research in spintronics and materials characterisation. To enable such progress, highly precise and accurate automation software is required. PICA (Python-based Instrument Control and Automation) is a modular open-source software suite designed to automate advanced transport measurements for electronic devices and material samples. PICA is designed as a versatile framework capable of operating on any standard laboratory workstation. It provides an extensible, unified graphical user interface (GUI)-based standalone program to coordinate high-precision instruments, specifically ultra-low current source (DC/AC) units, nanovoltmeters, high-resistance electrometers, impedance analyser, and temperature controllers. Built on the robust Python scientific ecosystem, PICA leverages community standard libraries as an alternative to licensed commercial software for instrument control. By utilising threading and multiprocessing capabilities, PICA ensures that the entire hardware ecosystem functions seamlessly and as a single cohesive unit. This allows the system to perform automated protocols, including temperature-dependent wide ranges of resistance measurement ( 10 − 8 - 10 16 Ω), current-voltage (I-V) characterisation, capacitance characterisation and pyroelectric current measurement, and orchestrate measurements under varying magnetic fields and temperatures without requiring physical reconfiguration of the measurement setups.

lo,. co°,r.o,o, o, ,,. OSTI |under contract No. W.31.109-ENG-38. |Accordingly, the U.S. Government retains a |nonexcluslve, royalty-free license to pubUsh |or reproduce the published form of this |contribution, or allow others to do so, for | U.S,Govemrnent purposes. DISCLAIMER Tb.is report was prepared as an account of work sponsored by an agency of the United States Government.

Nanostructured particles offer outstanding diversities of applications in the fields of nanotechnology, nano-engineering, nano-biotechnology, etc. Morphological structure, size distribution, electronic behavior including intrinsic characteristics of nanoparticles depend on the source and synthesis methods. Here, an eco-friendly approach using microwave irradiation for the synthesis of zinc oxide (ZnO) nanoparticles has been reported. Zinc nitrate was used as a precursor whereas starch and D-glucose were used as capping and reducing agent, respectively. The synthesized nanoparticles were characterized by different instrumental methods including Ultraviolet-Visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and field emission scanning electron microscopy (FE-SEM). The characteristic λmax at 373 nm for ZnO nanoparticles was recorded from UV-Vis absorption spectrum in aqueous system. FT-IR spectrum showed a very sharp peak at 476.62 cm⁻¹ which confirmed the presence of Zn-O bond. The prepared ZnO was highly crystalline having wurtzite structure and the crystallite size was calculated to be 24.41 nm obtained from XRD analysis. FE-SEM images showed that the synthesized ZnO nanoparticles had near- spherical morphology and particle size was found in the range of 40–90 nm. The antibacterial and anti-biofilm application of ZnO nanoparticles were studied and inhibition zones of Gram negative Salmonella typhi (S. typhi), Klebsiella spp., Escherichia coli (E. coli) and Gram positive Staphylococcus aureus (S. aureus)- 8a were found to be 11 mm, 12 mm, 11.5 mm and 13.5 mm, respectively. Besides, ZnO nanoparticles also showed excellent photocatalytic activity against methylene blue dye solution. The easy and eco-friendly fabrication method would play vital role in other nanoparticles synthesis to meet the demand in textile industry, agriculture and medical sectors.

The deformation and strengthening behavior of an ultra-fine grained (UFG) Al fabricated via powder metallurgy was investigated over a wide range of homologous temperatures (T H). Our results reveal that the presence of a high density of g-Al 2 O 3 nanoparticles, located primarily at high angle grain boundaries (HAGBs), promoted remarkable stabilization of the Al grain structure up to T H ¼ 0.94. The 0.2% strain offset yield stress (YS 0.2) of the materials annealed at 600 C for 24 h with grain sizes (d 3D) of 0.57, 1.67, 2.33 and 2.99 mm was systematically studied from room temperature (RT) to 600 C. Our study reveals that with decreasing d 3D the strain hardening ability of the materials gradually decreased, and this behavior became pronounced at elevated T, which was attributed to the onset of plastic instability. The YS 0.2 of the materials at all T followed the relation YS 0.2 ¼ a þ k d 3D À0.5. As determined on the basis of data interpolation, a positive transition from an established Hall-Petch (HP) relation at RT occurred at d 3D ¼ ~8 mm. As the parameter a was negative at RT and 300 C the documented strengthestructure relationship cannot be explained on the basis of a Hall-Petch relation. The g-Al 2 O 3 particles located at HAGBs did not contribute notably to RT strengthening, whereas GBs played a significant role in the overall strength. The materials showed a high YS 0.2 up to a T H of 0.94. The YS 0.2 was observed to be linearly correlated with the reciprocal square root of the d 3D and the coefficient k followed k ¼ 224.4 e0.376 T relation. The HP model overestimated the YS 0.2 values at elevated T namely for the materials with a smaller d 3D. It is proposed that softening occurred as a result of the g-Al 2 O 3 particles densely distributed within a 3D network, which were included in Hansen's strengthening model; particle strengthening played a role at elevated T.

We analyzed the intensity distribution resulted from the axial superposition of two Laguerre-Gauss beams. It is found that the intensity spatial distribution can be transformed from interference patterns with uniform maxima and round holes or radial petals, to one consisting of separated rings, by simply changing of the interrelations between constructive parameters. The propagation robustness of two Laguerre-Gauss beam superposition is investigated for different ranges of the constructive parameter values using experimental and simulation results. Combinations of different optical angular momentum states can be obtained, transmitted and read, with almost the same efficiency in the detection process.

A spheroidal Al 3 (Zr,Sc) precipitate with a double-shell structure, comprising a Sc-enriched core enveloped by a Zr-enriched inner shell and a Sc-enriched outer shell (~9 nm in thickness), appears in an Ale0.2Zre0.1Sc alloy cable after thermomechanical treatment. The average diameter of the spheroidal Al 3 (Zr,Sc) precipitate is approximately 80 nm. The double-shelled Al 3 (Zr,Sc) precipitate presents three different interfaces and is semi-coherent with the Al matrix. Atom probe tomography (APT) analyses further show that the outer shell of Al 3 (Zr,Sc) precipitate is Sc element enrichment. The electrical conductivity of Ale0.2Zre0.1Sc alloy cable increases by 6.5 MS/m within the aging time from 0.2 to 100 h at 350 C, with double-shelled Al 3 (Zr,Sc) precipitate.

Polycrystalline metals with fine grains are highly possible to possess superplasticity via grain boundaries sliding (GBS). However, the mechanism of stabilizing the fine grains and releasing grain boundary strain incompatibilities to maintain GBS has puzzled the researchers for several decades. Here, a classic example is represented by the Au-Sn eutectic (ζ-Au 5 Sn + δ-AuSn) alloy with micrometer-sized equiaxed grains, which achieved 2430% tensile strain at 473 K. Characterization at nanoscale reveals, unexpectedly, the universal occurrence of spinodal-like decomposition in one of the eutectic phases (δ-AuSn phase) in the Au-Sn alloy. The occurrence of the spinodal-like decomposition is energetically favorable. Therefore, the system's free energy was minimized by the spinodal-like decomposition rather than grain growth. Micrometer-sized grains were thus maintained at relatively high temperatures for maintaining GBS. In addition, the stacking faults (SFs) were generated in the spinodal-like decomposed substructures during deformation. SFs coordinated the strain incompatibilities during GBS and contributed to the plastic flow during superplasticity. In the present Au-Sn alloy, the spinodal-like decomposition is the root cause to stabilize the fine grains, eventually leading to outstanding superplasticity. This study enriches our fundamental understanding of the relation between spinodal-like decomposition and mechanical performance. It also provides new insights into the design of polycrystalline metals to achieve superplasticity.

The amount of electrode wear in micro-EDM has a direct effect on the dimensional accuracy of the machined hole. Therefore, improving the corrosion resistance of electrodes in micro-EDM is still of great interest. The effective coating of thin film for the micro tool electrodes in the case of micro-EDM can lead to minimize the electrode wear which eventually improve the productivity and machining quality. In the present study, experiments were performed on micro-EDM using carbon coated tool electrode and optimized using Taguchi-Topsis to investigate optimum levels of Depth of cut (Z) and overcut (OVC). It was concluded that optimum conditions had improved significantly using carbon coated micro tool electrode. Optimal levels of technological parameters include V = 160 V, C = 10000 pF, RPM = 600 rpm, and Zopt = 2.525 mm, OVCopt = 65.257 m. The quality of the machined surface with the coated electrode at optimal conditions is analysed and evaluated. The Topsis method is a suitable solution to this problem, and the steps to perform the calculation in this technique are simple.

The microstructure of a cobalt-base alloy (Co-Cr-Mo) obtained by the investment casting process was studied. This alloy complies with the ASTM F75 standard and is widely used in the manufacturing of orthopedic implants because of its high strength, good corrosion resistance and excellent biocompatibility properties. This work focuses on the resulting microstructures arising from samples poured under industrial environment conditions, of three different Co-Cr-Mo alloys. For this purpose, we used: 1) an alloy built up from commercial purity constituents, 2) a remelted alloy and 3) a certified alloy for comparison. The characterization of the samples was achieved by using optical microscopy (OM) with a colorant etchant to identify the present phases and scanning electron microscopy (SE-SEM) and energy dispersion spectrometry (EDS) techniques for a better identification. In general the as-cast microstructure is a Co-fcc dendritic matrix with the presence of a secondary phase, such as the M 23 C 6 carbides precipitated at grain boundaries and interdendritic zones. These precipitates are the main strengthening mechanism in this type of alloys. Other minority phases were also reported and their presence could be linked to the cooling rate and the manufacturing process variables and environment.

Li 2 TiO 3 /Ni foam composites were prepared by a solid-state reaction process. They crystallized in the monoclinic Li 2 TiO 3 structure with C2/c space group. SEM images show that the Li 2 TiO 3 particles are monodispersed crystallites of average size 49 nm, infused into porous scaffold Ni foam. As an anode in lithium battery, the composite delivered a discharge capacity of 153 mAh g À1 in an aqueous electrolyte and retained 95% of its initial capacity after 30 cycles. Moreover, the Li 2 TiO 3 /Ni foam composite as a negative electrode of pseudo-supercapacitor delivered a specific capacitance of 593 F g À1 and retained 95% of its initial capacitance after 1000 cycles. The enhanced capacity of Li 2 TiO 3 /Ni composite is due to porous scaffold Ni foam, which provides high conductivity to the Li 2 TiO 3 particles and high effective surface area for redox reactions. The performance of the Li 2 TiO 3 /Ni foam as an electrode material for both lithium-ion batteries (LIBs) and supercapacitors (SCs) shows that this composite is promising for energy storage devices.

This study provides a thorough characterization of the stone and earth-based construction materials from the Bronze Age funerary site of Bocapucheros (Almagro, Spain), emphasizing their composition, structural roles, absolute dating (14 C) and degradation processes. The load-bearing system consists exclusively of masonry walls built with locally sourced quartzitic blocks, shaped and assembled using manual techniques. Structural elements, including lintels and corbelled vaults, display different types of fracture modes caused by long-term mechanical and environmental stresses. Despite these damages, the overall stability is preserved thanks to a robust design that effectively distributes compressive loads. A multi-phase construction sequence is proposed, encompassing site preparation, foundation laying, wall assembly, and corbelled pseudo-dome roofing. The mortars are earth-based, primarily composed of aluminosilicate clays such as muscovite and kaolinite, combined with varying proportions of quartz aggregates, alongside traces of carbonates and iron oxides. Analyses performed using radiocarbon dating, X-ray diffraction, Fouriertransform infrared spectroscopy, Raman spectroscopy, X-ray fluorescence, and backscattered electron microscopy coupled with energy-dispersive X-ray spectroscopy confirm the compositional diversity and the presence of volcanic and metamorphic components consistent with the local geological context. Thermogravimetric and calorimetric data reveal dehydration and decarbonation processes aligned with the behavior of clay minerals and carbonates. This integration of mechanical resilience, material heterogeneity, and advanced corbelling techniques reflects sophisticated architectural knowledge within Bronze Age society. These findings advance the understanding of prehistoric construction technologies and support ongoing efforts in cultural heritage preservation. //
Este estudio ofrece una caracterización exhaustiva de los materiales de construcción a base de piedra y tierra procedentes del yacimiento funerario de la Edad del Bronce de Bocapucheros (Almagro, España), haciendo hincapié en su composición, funciones estructurales, datación absoluta (14 C) y procesos de degradación. El sistema portante está compuesto exclusivamente por muros de mampostería construidos con bloques de cuarcita de origen local, tallados y ensamblados mediante técnicas manuales. Los elementos estructurales, incluidos los dinteles y las bóvedas en voladizo, presentan diferentes tipos de fracturas causadas por tensiones mecánicas y ambientales a largo plazo. A pesar de estos daños, la estabilidad general se mantiene gracias a un diseño robusto que distribuye eficazmente las cargas de compresión. Se propone una secuencia de construcción en varias fases, que abarca la preparación del emplazamiento, la colocación de los cimientos, el montaje de los muros y la cubierta en voladizo en forma de pseudocúpula. Los morteros son a base de tierra, compuestos principalmente por arcillas de aluminosilicato, como moscovita y caolinita, combinadas con proporciones variables de agregados de cuarzo, junto con trazas de carbonatos y óxidos de hierro. Los análisis realizados mediante datación por radiocarbono, difracción de rayos X, espectroscopia infrarroja por transformada de Fourier, espectroscopia Raman, fluorescencia de rayos X y microscopía electrónica de retrodispersión junto con espectroscopia de rayos X de energía dispersiva confirman la diversidad composicional y la presencia de componentes volcánicos y metamórficos coherentes con el contexto geológico local. Los datos termogravimétricos y calorimétricos revelan procesos de deshidratación y descarbonatación en consonancia con el comportamiento de los minerales arcillosos y los carbonatos. Esta integración de resistencia mecánica, heterogeneidad de los materiales y técnicas avanzadas de voladizo refleja los sofisticados conocimientos arquitectónicos de la sociedad de la Edad del Bronce. Estos hallazgos contribuyen a mejorar la comprensión de las tecnologías de construcción prehistóricas y respaldan los esfuerzos actuales por preservar el patrimonio cultural.

Accurate prediction of wear behavior in polymer nanocomposites remains challenging due to the coupled influence of operating conditions and evolving surface morphology. In this study, a surface-aware triboinformatics framework is proposed to predict the dry sliding wear behavior of multi-walled carbon nanotube (MWCNT) reinforced epoxy composites by integrating operating parameters with run-wise atomic force microscopy (AFM) surface descriptors. Wear experiments were conducted using a Taguchi L16 design by varying CNT content (0-0.75 wt.%), applied load (10-40 N), sliding speed (183-458 rpm), and sliding distance (500-1250 m). AFM-derived parameters, including Ra, Rq, Z-range, and surface area difference, were extracted from the worn surface corresponding to each experimental run. Multiple regression-based machine learning models were evaluated using leave-one-out cross-validation, with ensemble-based models providing the best predictive performance (R 2 > 0.85 with low RMSE and MAE). Feature importance and partial dependence analyses identified CNT content as the dominant factor controlling wear reduction, followed by Zrange and Ra, highlighting the critical role of surface damage severity. Neat epoxy exhibited a maximum wear loss of 0.444 mg, whereas the 0.75 wt.% CNT composite showed values as low as 0.003 mg under comparable conditions, corresponding to a reduction of approximately 99%. The proposed framework enables mechanistically interpretable wear prediction and supports the design of durable polymer composites, contributing to SDG 9 (Industry, Innovation and Infrastructure) and SDG 12 (Responsible Consumption and Production).

Authors' Contributions: Each author made an equal contribution to the conception and design of the study. All authors have reviewed and approved the final version of the manuscript for publication. Transparency: The authors affirm that this manuscript presents an honest, accurate, and transparent account of the study. All essential aspects have been included, and any deviations from the original study plan have been clearly explained. The writing process strictly adhered to established ethical standards.

This review provides a comprehensive overview of recent advancements in aluminum-based conductor alloys engineered to achieve superior mechanical strength and thermal stability without sacrificing electrical conductivity. Particular emphasis is placed on the role of microalloying elements-particularly Sc and Zr-in promoting the formation of coherent nanoscale precipitates such as Al 3 Zr, Al 3 Sc, and core-shell Al 3 (Sc,Zr) with metastable L1 2 crystal structures. These precipitates contribute significantly to high-temperature performance by enabling precipitation strengthening and stabilizing grain boundaries. The review also explores the emerging role of other rare earth elements (REEs), such as erbium (Er), in accelerating precipitation kinetics and improving thermal stability by retarding coarsening. Additionally, recent advancements in thermomechanical processing strategies are examined, with a focus on scalable approaches to optimize the strength-conductivity balance. These approaches involve multi-step heat treatments and carefully controlled manufacturing sequences, particularly the combination of cold drawing and aging treatment to promote uniform and effective precipitation. This review offers valuable insights to guide the development of cost-effective, high-strength, heat-resistant aluminum alloys beyond conductor applications, particularly those strengthened through microalloying with Sc and Zr.

The effect of prior constrained groove pressing on friction stir processing (FSP) of pure copper was investigated. The results illustrate the development of high strain and strength of FSP samples along with an increased strength base metal as a result of applying for a prior constrained groove pressing (CGP) pass. The influences of further FSP passes on the microstructures, and mechanical properties were also shown. The microstructural evaluation of the specimens indicated up to 10 times grain size reduction in FSP specimens as well as equiaxed microstructural morphology. Mechanical properties of the specimens were carried out through tensile and microhardness tests. It was demonstrated that the FSP could improve the strength and ductility of the specimens simultaneously through improved mechanical properties of the base metal resulting from prior CGP. The performed calculations show that values of dislocation density of the CGPed specimens experienced significant change after appl...

In this paper, geometrical roughness numbers named RNx, RNy and RNS are formulated as a possible analytical tool for cement-based material surface characterization using coherence scanning interferometry (CSI) and STIL confocal microscopy technique (SCM). Recently, cement paste surface maps have been used to establish a link between surface statistical roughness parameters and the measuring scale (Apedo et al., 2015). The objectives of the present paper are to study how geometrical roughness numbers can be used as a tool to analyze the colonization of cement-based material surfaces by microorganisms as well as to perform other subsequent studies. Observations from a series of images acquired using both techniques (CSI and SCM) on both polished and unpolished samples are described. Using a new method named “window resizing”, the results from CSI are compared with those from SCM. It appears that the surface available for colonization (convolution) is smaller than the surface developed...

Diaper waste was calcined above 400°C after impregnated in the solution of nickel nitrate. The as-prepared diaper waste-derived materials were used as magnetic catalysts for the synthesis of glycerol carbonate (GC). Structure and catalytic ability investigations on the catalysts calcined at different temperatures indicated that calcination temperature was an important factor affecting the property of catalysts. It was found that the catalyst obtained at the calcination temperature of 700°C (named DW-Ni-700) showed the best performance. When DW-Ni-700 was used in the synthesis of GC, GC yield reached 93.2%, and the magnetic property of DW-Ni-700 facilitated the catalyst separation process. Meanwhile, DW-Ni-700 showed high reusability in the reaction. After four times reuse of DW-Ni-700, GC yield decreased less than 4%.

Eutectic alloys have a great importance both from academic as technological point of view. For technological applications such casting, welding and joining, these systems offer lower melting point than the pure elements and good fluidity. This property is the distance travelled by the liquid metal until it is stopped by solidification when is forced to flow through a channel of small cross section and is called Fluidity Length (L F ). Physical variables associated with the process are: metallostatic pressure, heat extraction rate at the metal-mold interface, overheating of the liquid metal and the physico-chemical properties of metal or alloy (latent heat of fusion, density, viscosity, surface tension and solidification mode). In general, pure metals and alloys of eutectic composition have the highest values of fluidity, whilst intermediate composition alloys with greater solidification range show lesser fluidity lengths. Taking into account that the chemical composition plays a fun...

The microstructure of a cobalt-base alloy (Co-Cr-Mo) obtained by the investment casting process was studied. This alloy complies with the ASTM F75 standard and is widely used in the manufacturing of orthopedic implants because of its high strength, good corrosion resistance and excellent biocompatibility properties. This work focuses on the resulting microstructures arising from samples poured under industrial environment conditions, of three different Co-Cr-Mo alloys. For this purpose, we used: 1) an alloy built up from commercial purity constituents, 2) a remelted alloy and 3) a certified alloy for comparison. The characterization of the samples was achieved by using optical microscopy (OM) with a colorant etchant to identify the present phases and scanning electron microscopy (SE-SEM) and energy dispersion spectrometry (EDS) techniques for a better identification. In general the as-cast microstructure is a Co-fcc dendritic matrix with the presence of a secondary phase, such as th...