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In this study, Cu–10W and 2 wt%Y 2 O 3 /Cu–10W composites were successfully prepared via mechanical ball milling and spark plasma sintering. Hot compression experiments on the two materials were carried out in the temperature range of 300°C-600 °C and in the strain rate range of 0.01 s−1–10 s−1. The hot deformation activation energy of the two materials was calculated and a constitutive equation was established. The optimum hot deformation process parameters were obtained according to a hot processing map. The effects of Y 2 O 3 on the thermal deformation behavior of the Cu–10W composites and their microstructures were investigated, and the results showed that Y 2 O 3 could enhance the stability of Cu–10W at high temperatures. The activation energies of thermal deformation of Cu–10W and 2 wt%Y 2 O 3 /Cu–10W were 159.56 kJ/mol and 129.85 kJ/mol, respectively. Moreover, Y 2 O 3 improved the interfacial bonding strength of Cu and W in the Cu–10W material, effectively preventing the generation of microcracks and pores during the high-temperature compression process; Y 2 O 3 provides more nucleation sites in the recrystallization process, which is favorable for the excitation of recrystallization. A low strain rate at high temperatures favors the occurrence of recrystallization, and the 2 wt%Y 2 O 3 /Cu–10W composites tend to exhibit discontinuous dynamic recrystallization (DDRX) under high-Z-value conditions and continuous dynamic recrystallization (CDRX) under low-Z-value conditions. [ABSTRACT FROM AUTHOR]

Sphalerite (ZnS) is a sulfide found in a large variety of ore deposits and is frequently hosted in metamorphic terranes that have undergone deformation and related recrystallization. However, the deformation mechanisms of sphalerite are still poorly understood because recrystallization evidence is barely visible under an optical microscope and may reflect complex and frequently multistage mechanisms. Furthermore, sphalerite may host up to a few thousands of parts per million of critical metals such as gallium (Ga), germanium (Ge), and indium (In). Metamorphic conditions and dynamic recrystallization may have induced local or total redistribution of these elements. Modern techniques such as electron backscattered diffraction analyses (EBSD) and laser-induced breakdown spectroscopy (LIBS) applied on sphalerite allow for the examination of grain boundaries, crystal-plastic deformation, and internal chemical diffusion, which classically reflect active deformation mechanisms. In this study, a microstructural and in situ chemical comparison between four sphalerite types (types 1, 2, 3, and 4) has been made for the first time. The four sphalerite types present different deformation imprints, although they are hosted in a similar geological setting: the Pyrenean Axial Zone and the Montagne Noire Variscan massifs (France). Based on EBSD and LIBS mapping, we describe two regional sphalerite growth stages composed of dark red crystals with polygonal shape (type 1, Bentaillou-Liat deposit) and light- to dark-brown euhedral crystals (type 3, Saint Salvy deposit). New investigation at microscale on sphalerite grains from the Saint-Salvy deposit shows late Cu-Ge-Ga enrichment not only in specific sector zonings but also along grain boundaries, growing crystal edges, and in low-angle misorientations or twin boundaries. Following a deformation event that probably occurred during the Pyrenean-Alpine orogeny, these two sphalerite mineralizations have both endured plastic deformation in a dislocation creep regime and dynamically recovered by subgrain rotation (SGR) mechanism. Two mechanisms of Cu-Ga-Ge spatial redistribution are observed and are key processes for the crystallization of Cu-Ga-Ge-rich minerals in sphalerite veins. The first mechanism involved the in situ redistribution of Cu-Ga-Ge contents from a pre-existing concentration in the sphalerite lattice (type 3, Arre deposit), creating Ge-sulfides (briartite), probably during Pyrenean-Alpine orogeny. Formation of this type of Ge-mineral may be related to solid-state diffusion processes. The second mechanism is associated with the circulation of a Cu-Ga-Ge-rich fluid in surrounding rocks. In the pre-existing polygonal sphalerite from Late-Variscan veins (type 2, Pale Bidau deposit), millimeter-size bands of small (<50 μm), recrystallized sphalerite grains are locally observed. Those domains contain inclusions of Cu (chalcopyrite) and Ga and Ge minerals (brunogeierite, carboirite). Fluid-induced diffusion in the polygonal sphalerite aggregates may occur with superimposed dynamic recrystallization, such as the Late-Variscan veins (type 2, Pale Bidau-type). During post-Variscan time, this fluid enriched in Cu-Ga-Ge largely circulated in the upper-crust of this Variscan terrane. This study highlights the key importance of coupled textural (EBSD) and in situ chemical analyses (LIBS) of diverse sphalerite types at a regional scale to indirectly unravel the origin of vein mineralization, and their related critical metal distribution. [ABSTRACT FROM AUTHOR]

Cobalt (Co) and nickel (Ni) are critical metals for modern renewable energy technologies as well as essential micronutrients for terrestrial plant health and marine primary production. Both metals are commonly surface-adsorbed onto and/or structurally-incorporated into iron (oxyhydr)oxide minerals, such as goethite (α-FeOOH), that are ubiquitously present in soils and sediments at the Earth's surface. In sub- and anoxic environments, aqueous ferrous iron (Fe(II)) generated from dissimilatory Fe(III) reduction can induce the recrystallization of goethite and subsequently influences the speciation and mobilization of associated metals, e.g., Co(III) being reduced to Co(II). While it is generally considered that divalent Co and Ni behave similarly at goethite-water interfaces, there lacks a direct comparison of their cycling through goethite in response to Fe(II)-catalyzed recrystallization. Here, under circumneutral anoxic conditions with and without addition of aqueous Fe(II), we performed batch reaction experiments on Co(II)-substituted goethite and Co(II) and Ni(II) sorption experiments on pure goethite. The redox state and coordination environment of Co associated with goethite were determined using high energy resolution fluorescence detected X-ray absorption spectroscopy at the Co K-edge, and the distribution of solid-bound Co and Ni in goethite following sorption was revealed by sequential dissolution. Our results show that substitution of Co(II) for Fe(III) in goethite has less negative feedback on Fe(II)-catalyzed recrystallization than Ni(II), which may be related to their differing structural distortions as evidenced by EXAFS. In the absence of Fe(II), aqueous Co(II) is more favourably adsorbed onto and incorporated deeper into goethite than Ni(II), suggesting that Co(II) is more structurally compatible with goethite. The presence of Fe(II) markedly enhances the structural incorporation of both Co(II) and Ni(II) as a result of goethite recrystallization, which in turn can be inhibited by the accumulation of metals at the mineral surface. Furthermore, structurally-incorporated Co(II) is more difficult to be released back into solution (i.e. sum of aqueous and extract fractions) than Ni(II) during Fe(II)-catalyzed goethite recrystallization. Overall, our work highlights the significant differences between Co(II) and Ni(II) in their cycling at goethite-water interfaces and intricate interplay with Fe(II)-catalyzed recrystallization. This improves our understanding of their mobilization and distribution in anoxic goethite-rich systems and can provide useful insights for their enrichment and extraction from natural and artificial laterites generated from the enhanced weathering of ultramafic mine tailings. [ABSTRACT FROM AUTHOR]

As the key material of aero-engine turbine blades, nickel-based single-crystal superalloys are in long-term service under high temperature, high pressure, and high rotational speed and are prone to fatigue failure. DD6 superalloy is a nickel-based single-crystal superalloy widely used in advanced aero-engines in China. In this work, the recrystallization study of laser shock peened nickel-based single-crystal superalloy was carried out; the finite element model of laser shock peened nickel-based single-crystal superalloy was established, and the influence law of laser shock peening overlap rate and laser shock peening times on the residual stress field was obtained. Secondly, the effects of different laser shock peening temperatures on the material properties of the nickel-based single-crystal superalloy after heat treatment were investigated. It was concluded that heating up to 300 °C during laser shock peening of the nickel-based single-crystal superalloy can effectively suppress the recrystallization. [ABSTRACT FROM AUTHOR]

The prominent chemical bath deposition (CBD) method leverages tin dioxide (SnO2) as an electron transport layer (ETL) in perovskite solar cells (PSCs), achieving exceptional efficiency. The deposition of SnO2, however, can lead to the formation of oxygen vacancies and surface defects, which subsequently contribute to performance challenges such as hysteresis and instability under light‐soaking conditions. To alleviate these issues, it is crucial to address heterointerface defects and ensure the uniform coverage of SnO2 on fluorine‐doped tin oxide substrates. Herein, the efficacy of tin(IV) chloride (SnCl4) post‐treatment in enhancing the properties of the SnO2‐ETL and the performances of PSCs are presented. The treatment with SnCl4 not only removes undesired agglomerated SnO2 nanoparticles from the surface of CBD SnO2 but also improves its crystallinity through a recrystallization process. This leads to an optimized interface between the SnO2‐ETL and perovskite, effectively minimizing defects while promoting efficient electron transport. The resultant PSCs demonstrate improved performance, achieving an efficiency of 25.56% (certified with 24.92%), while retaining 95.84% of the initial PCE under ambient storage conditions. Additionally, PSCs treated with SnCl4 endure prolonged light‐soaking tests, particularly when subjected to quasi‐steady‐state‐IV measurements. This highlights the potential of SnCl4 treatment as a promising strategy for advancing PSC technology. [ABSTRACT FROM AUTHOR]

In this work, 2195 Al–Li alloys with various precipitation microstructures were obtained by homogenization treatment followed by air-cooling (AC), discontinuous cooling (DC), and furnace-cooling (FC), and then tested by hot compression at different temperatures. The results show that the flow stresses of all specimens decrease with temperature and the peak stresses of AC, DC and FC specimens decrease in order at the same temperature. For FC samples, coarse pre-precipitates diminish the deformation resistance due to the reduction of solid solution strengthening and precipitation strengthening. Dynamic softening at low temperatures is significantly greater than that at high temperatures, except for the anomalous softening of the FC specimen at 520 °C due to stress release by cracks. At 370–420 ​°C, the dynamic softening of the AC specimen is more significant than the other samples, resulting from dynamic precipitation and precipitate coarsening. Furthermore, there is considerable dynamic recrystallization (DRX) in FC samples and not in AC and DC samples, although their precipitates coarsen to similar levels at low temperatures. This suggests that DRX is associated with the particle-stimulated nucleation mechanism by regularly arranged precipitates. The banded or regularly arranged precipitates divide the Al matrix into multiple confined units, hindering dislocations and (sub)grain boundary movement, and thus promoting the development of sub-grains and DRX. [ABSTRACT FROM AUTHOR]

The recrystallization behavior of ferrite single phase in ultrahigh‐strength low‐alloy (UHSLA) steels, with different titanium concentrations (1000, 1500, and 2000 ppm) is presented. Utilizing detailed dilatometer tests, we identified disparities between the observed austenite onset temperatures and those predicted using the JMatPro 13 program and ThermoCalc. This study accentuates the combined effects of titanium, niobium, and reduced manganese levels on the initiation of the ferrite‐to‐austenite transformation. The Hall–Petch relationship was used to draw a correlation between titanium concentration, yield strength, and grain size. Moreover, we explored the recrystallization kinetics of these steels using the Johnson–Mehl–Avrami–Kolmogorov (JMAK) model, pinpointing titanium's crucial role in modulating the recrystallization dynamics. These findings have significant implications for advancements in steel manufacturing, enhancing the quality and performance of UHSLA steels in industrial applications. [ABSTRACT FROM AUTHOR]

The present work aims to elucidate the mechanism of microstructural evolution in different regions of nano-SiC particles reinforced aluminum matrix composites prepared by friction stir processing (FSP) on its electrochemical behavior. Electron backscatter diffraction technique (EBSD) and transmission electron microscopy (TEM) were employed to characterize the microstructure evolution of stir zone (SZ), advancing side thermomechanically affected zone (AS-TMAZ), retreating side thermomechanically affected zone (RS-TMAZ) and base metal (BM). The electrochemical behaviors of the above zones were investigated using electrochemical tests. A homogeneous and fine microstructure is formed in SZ, not only the nano-SiC is homogeneously distributed within the grains with an average grain size of 3.5 μm, but also the recrystallized grains account for the highest percentage of 85 %. The potentiodynamic polarization curve indicates that the corrosion current densities of the BM, RS-TMAZ, AS-TMAZ and SZ are 0.89, 0.39, 0.85 and 0.36 μA/cm2, respectively, while the polarization impedances are 33.40, 51.42, 48.72 and 73.79 kΩ cm2, respectively. Combining the Nyquist and Bode plots analysis, the optimal electrochemical corrosion resistance is in SZ. The fine and homogeneous recrystallized grains in SZ significantly improve its electrochemical corrosion resistance. This is mainly ascribed to the increase in crystal defects as a result of the increase in grain boundaries, elevating the electron scattering. Simultaneously, the increase in high-energy state grain boundaries is beneficial to the rapid formation of a thicker passivation film. [ABSTRACT FROM AUTHOR]

In order to obtain the sharp cube texture, a new process, the intermediate annealing rolling technique, has been introduced to prepare the Ni7W substrate. In this paper, a cubic texture content up to 98.5% within 10° of the standard cubic orientation is obtained in the final substrate and the influence of this improved rolling technique on the cube texture formation has been discussed. The results show that the increased cube texture in the Ni7W substrate is caused by the optimized deformation texture and the increased nucleated fraction of the cube grains. [ABSTRACT FROM AUTHOR]

The effects of cold rolling reduction on the microstructure, recrystallization behavior, and magnetic properties of 3.0%Si-0.8%Al-0.3%Mn steel were studied by X-ray diffraction (XRD) and electron backscatter diffraction (EBSD). With the reduction rates of 78%, 85% and 87% in the cold rolled sheet, the width of the deformation band becomes narrower, the number of intragranular shear bands decreases, and the proportion of grain boundaries increases. The intensity of the α and γ fibers texture in the cold rolled sheet is enhanced, and the annealed sheet is dominated by the γ fibers texture and the content increases from 26.0% to 34.5%. During the recrystallization process, the Goss and γ-grains nucleate first. The λ-grains nucleate mainly at the grain boundaries of the deformed α-grains, and the α-grains ultimately recrystallize. With the increase in the cold rolling reduction rate, the γ-grains develop into the main texture due to a large amount of nucleation at the deformation band and grain boundary. The λ-grains with a high mobility do not have a numerical advantage, and the increase in the texture content is very small. The content of the unfavorable γ fiber texture in the annealed sheet increases, the magnetic induction intensity B50 decreases, Pe and Pt decrease significantly, and the critical grain size with the lowest iron loss decreases from 136.2 to 109.4 μm. [ABSTRACT FROM AUTHOR]

The isothermal crystallization process of felodipine has been investigated using the time-domain Nuclear Magnetic Resonance (NMR) method for amorphous bulk and ground samples. The obtained induction and crystallization times were then used to construct the time–temperature-transformation (TTT) diagram, both above and below the glass transition temperature (Tg). The Nose temperature was found equal to 363 K. Furthermore, the dynamics of crystalline and amorphous felodipine were compared across varying temperatures. Molecular dynamics simulations were also employed to explore the hydrogen-bond interactions and dynamic properties of both systems. [ABSTRACT FROM AUTHOR]

In the present study, considering the features and advantages of solid-state welding methods as compared with fusion welding methods such as arc welding, laser welding induction welding, and solid-state welding, they are used to connect CK45 steel to AISIS 304L steel to achieve the desired mechanical and metallurgical properties through experimental and practical tests, by trial and error, suitable parameters of distance, depth, and advance are obtained for welding, and finally a healthy and desirable weld is obtained. The purpose of the present study is to evaluate the weldability of CK45 steel to AISIS 304L steel by friction stir welding method. The distance, advance, and penetration depth parameters were experimentally determined as 950 rpm, 24 mm/min, and 0.35 mm, respectively, to obtain a healthy weld in terms of appearance. Then, through mechanical and metallurgical tests, the effect of the input parameters on the friction stir welding process was determined. The mechanical and metallurgical properties were also evaluated. The results show that the structure of the onion rings in the welding area is caused by the friction stir welding process, which is caused by the massive plastic deformation and the heat generated during the process. The scanning electron microscope image of the welded section of the steel sample shows the formation of a pearlite structure. Considering the severe plastic deformation and dynamic recrystallization in the friction stir welding process, the results obtained from the welding of dissimilar CK5 and AISI304 L show better mechanical properties and acceptable strength. [ABSTRACT FROM AUTHOR]

Basalt-hosted monocentric agates from Bou Hamza (Morocco) were examined to unravel a discrete relationship between moganite content, water content, and the abundance of various types of chalcedony/quartz microtextures, so that the agate-forming process is refined. Herein, moganite content is noticeably low in length-slow chalcedony (quartzine, up to 18 wt.%), as compared with the co-occurring length-fast (LF) chalcedony (up to 31 wt.%). Such a type of disparity reflects a stabilization of the crystallization front during the formation of chalcedonic bands. Recrystallization-related quartz types (i.e. feathery and mosaic/jigsaw puzzle) show low and high moganite content (0 and up to 34 wt.%, respectively) since they have likely originated from different silica precursors (i.e. opaline and chalcedonic, respectively). Meanwhile, the initial formation of mosaic quartz can be exclusively witnessed in the so-called zebraic variety of length-fast chalcedony (i.e. with twisted fibres) that should be hence regarded as a ,,metastable" variety of silica though. The range of total water content remains quite stable across chalcedonic bands (0.5–0.6 wt%) and reaches the highest values (0.7 wt%) in feathery quartz. However, there is rather a general negative relationship between the content of molecular water and silanol-group water. This can stem from the recycling of water species following the condensation reaction of silanols within the agate geodes. The agates originated from Fe-Ti-bearing solutions that co-precipitated goethite, hematite, and rutile, but also contain minor low-grade carbonaceous material. [ABSTRACT FROM AUTHOR]

In this work the effect of 2% calcium on the structure, deformability and physicomechanical properties of Al-3%Mg‑0.8%Mn alloy is investigated. A hot rolling temperature of 400 °C for the alloy with calcium without prior homogenization appeared to be low, resulting in cold rolled sheets containing multiple defects, in contrast to a refrence alloy without calcium. During homogenization annealing at 550 °C aluminum-calcium eutectic is highly fragmented, which facilitates rolling. Evaluation of alloy with calcium resistance to recrystallization shows that hot-rolled sheets begin to lose strength after 250 °C, while for cold-rolled sheets this temperature is limited to 200 °C. Cold-rolled sheets of Al-3%Mg‑0.8%Mn alloy also have a temperature for the start of recrystallization of 250 °C, which is associated with liberation during hot rolling of nanosized dispersoids of Al6(Mn, Fe) phase, which as a result of heterogenization at 550 °C have micron sizes. At the same time, cold-rolled sheets with added calcium have higher hardness and yield strength after one-hour annealing at 400 °C (71/61 HV and 124/107 MPa). Relative elongation is also better for alloy with added calcium. It is also shown that calcium addition increases corrosion current density from 0.71·105 to 0.92·105 A/m2, while its value remains at the level for AMg5 alloy or grade 5182 alloy. [ABSTRACT FROM AUTHOR]

The textures of the β- and α-phases of the metastable β-titanium alloy Ti5321 after hot deformation were investigated by neutron diffraction. A hot-rolled bar was solutionized in the β-phase field and then hot compressed above and below the β-transus temperature. The initial texture after full recrystallization and grain growth in the β-phase field exhibits a weak cube component {001}<100> and minor {112}<110> and {111}<110> components. After hot compression, a <100> fiber texture is observed, increasing in intensity with compression temperature. Below the β-transus temperature, dynamic recrystallization of the β-phase and dynamic spheroidization of the α-phase interact strongly. The texture of the α-phase is a <11–20> fiber texture, increasing in intensity with decreasing compression temperature. The mechanisms of texture formation during hot compression are discussed. [ABSTRACT FROM AUTHOR]

The incorporation of leucine (Leu), a hydrophobic amino acid, into pharmaceutically relevant particles via spray-drying can improve the physicochemical and particulate properties, stability, and ultimately bioavailability of the final product. More specifically, Leu has been proposed to form a shell on the surface of spray-dried (SD) particles. The aim of this study was to explore the potential of Leu in the SD protein/trehalose (Tre) formulation to control the water uptake and moisture-induced recrystallization of amorphous Tre, using lysozyme (LZM) as a model protein. LZM/Tre (1:1, w/w) was dissolved in water with varied amounts of Leu (0 - 40%, w/w) and processed by spray-drying. The solid form, residual moisture content (RMC), hygroscopicity, and morphology of SD LZM/Tre/Leu powders were evaluated, before and after storage under 22°C/55% RH conditions for 90 and 180 days. The X-ray powder diffraction results showed that Leu was in crystalline form when the amount of Leu in the formulation was at least 20% (w/w). Thermo-gravimetric analysis and scanning electron microscopy results showed that 0%, 5%, and 10% (w/w) Leu formulations led to comparable RMC and raisin-like round particles. In contrast, higher Leu contents resulted in a lower RMC and increased surface corrugation of the SD particles. Dynamic vapor sorption analysis showed that partial recrystallization of amorphous Tre to crystalline Tre·dihydrate occurred in the 0% Leu formulation. However, adding as little as 5% (w/w) Leu inhibited this recrystallization during the water sorption/desorption cycle. In addition, after storage, the formulations with higher Leu contents showed reduced water uptake. Instead of observing recrystallization of amorphous Tre in 0%, 5%, and 10% (w/w) Leu formulations, recrystallization of amorphous Leu was noted in the 5% and 10% (w/w) Leu formulations after storage. In summary, our study demonstrated that the addition of Leu has the potential to reduce water uptake and inhibit moisture-induced recrystallization of amorphous Tre in the SD protein/Tre powder system. [Display omitted] • Leu was in crystalline form when the amount of Leu in the SD LZM/Tre formulation was not less than 20 % (w/w). • The addition of as little as 5 % Leu could inhibit the recrystallization of amorphous Tre during the water sorption/desorption cycle. • Higher Leu contents resulted in a lower RMC and an increased surface corrugation of the SD particles. • Higher Leu contents led to less water uptake after storage. • Rather than recrystallization of amorphous Tre, recrystallization of amorphous Leu was observed in both 5% and 10% Leu formulations after storage. [ABSTRACT FROM AUTHOR]

Herein, the effect of nonmetallic inclusions (NMIs) on the microstructure and dynamic recrystallization (DRX) of Fe–23Mn–6Al–0.7C low‐density steel is studied. The specimens are separately added sulfur (S) and nitrogen (N) to change the characteristics of NMIs. As a result, the addition of S significantly increases the number of MnS inclusions and AlN–MnS complex inclusions in low‐density steel. The addition of N results in a significant increase in the size of NMIs. In the results, NMIs act as the heterogeneous nucleation sites for austenite and refine the as‐cast grains in low‐density steel. In addition, the treated specimens are subjected to a thermal compression simulation experiment. During the thermal compression process, discontinuous DRX is considered to be the main recrystallization method in the experimental low‐density steels. Meanwhile, the typical NMIs significantly accelerate the DRX within grains in low‐density steel through the mechanism of particle‐stimulated nucleation and continuous DRX. [ABSTRACT FROM AUTHOR]

To improve the ignition and combustion performance of boron (B), the B@ potassium perchlorate (KP) composite micro‐units are successfully prepared by recrystallization of solvent evaporation. The morphology and structural composition show that B@KP composite micro‐units are formed by the gentle recrystallization of KP at the heterogeneous interface between B particles and solvents. It is shown by thermal analysis that the initial thermal decomposition temperature of KP is reduced by 49 °C due to the reduction of particle size. In addition, the heat of 420 J/g released by the thermal decomposition of KP is beneficial to the evaporation of the oxide boron (B2O3) film on the surface of B, which reduces the initial oxidation temperature of B by 185 °C and improves the ignition performance of B. Interestingly, the oxygen (O2) released by the thermal decomposition of KP quickly reacts with B to release heat of 3608 J/g, which improves the combustion performance of B. The optimal mass ratio of B to KP is 1: 5, which results in the ignition delay time of 641 ms, a reduction of 19 ms compared to the physical mixed sample. The ignition delay times of other samples are 724 ms, 680 ms and 650 ms respectively, and B could not be ignited successfully. In the combustion process, all samples emit a bright green flame of B combustion, and even a fierce combustion flame like a mushroom cloud appears. In a word, the B@KP composite micro‐units have great potential for application in solid propellants. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum Naturalium Universitatis Pekinensis is the property of Editorial Office of Acta Scientiarum Naturalium Universitatis Pekinensis and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Equal Channel Angular Pressing (ECAP) is one of the severe plastic deformation methods that is applied to metals, alloys and composite materials in order to convert the normal grain structure into ultra-fine grain structure, so as to increase the strength of the metal and its ductility. The uniqueness of ECAP is that the severe plastic deformation apply large strains on the material without affecting the original dimensions of material. ECAP process was chosen among the other severe plastic deformation methods, because of its cost-effectiveness and simplicity. Die angle, corner angle, ECAP routes, number of passes and heat treatments have great impact on the micro-structure and mechanical properties of various materials. The grain refinement enhances the yield strength, tensile strength, hardness, ductility and corrosion resistance on ECAPed materials, which are commonly used for engineering and bio-medical applications. Many researchers have contributed greatly to this method. This article mainly focuses on the effect of ECAP die orientations and on novel ECAP methods that exclusively combines ECAP with heat treatment or hot working on aluminium, magnesium, titanium and other materials. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ti–10Cr alloy is a beta titanium alloy that exhibits variable Young's modulus, which can be beneficial for spinal implants. This study investigates the effects of cold deformation and heat treatment on the mechanical and biocompatibility properties of Ti–10Cr alloy. The ingot was homogenized, hot rolled, and annealed at various temperatures. Cold rolling was performed with different thickness reductions to examine the Young's modulus variation. Cell culture was employed to evaluate the biocompatibility. The microstructure and tensile test results of the heat-treated samples showed that recrystallization occurred during annealing, and 900 °C was the optimal heat treatment temperature. The Young's modulus exhibited the highest variation when the thickness was reduced by 10%. Moreover, the biocompatibility tests revealed that Ti–10Cr had higher biocompatibility than Ti–6Al–4V alloy. [ABSTRACT FROM AUTHOR]

In this study, we focused on the effects of various deformation amounts and subsequent heat treatment on σ-phase precipitation in CoCrFeMnNi high entropy alloy, known as Cantor alloy. Homogenized specimens with an initial FCC single-phase structure were deformed to various shear strains (1.1-25.8) using high-pressure torsion (HPT). This process resulted in a variety of deformation microstructures, with low to medium shear strains leading to the formation of twin-matrix lamellae intersected by shear bands, while high shear strains resulted in nanocrystalline structures. After deformation, the specimens were heat-treated at 700°C for up to 5 h, which led to recrystallization of the FCC matrix accompanied by precipitation of σ phase. The kinetics of recrystallization and precipitation and their interactions during the heat treatment were greatly different among the specimens with different degrees of pre-deformation. Notably, the precipitation of σ phase was accelerated in the specimens subjected to higher shear strains, particularly in those with nanocrystalline structures. The increased rate of precipitation was beneficial for grain refinement since the presence of numerous precipitates within the recrystallized microstructures inhibited their grain growth. Tensile testing of the heat-treated specimens displayed various combinations of strength and ductility, with specimens subjected to higher predeformation exhibiting enhanced strength due to finer recrystallized grain sizes and larger fractions of precipitates. Our findings offer valuable insights into fabrication processing of HEAs, aiming to optimize microstructure and mechanical properties for potential engineering applications. [ABSTRACT FROM AUTHOR]

In this study, 48 hot-rolling processing conditions were designed to investigate the influences of thermomechanical processing parameters on the recrystallization behavior and texture development. The hot-rolling experiments were conducted using the thermomechanical simulator Gleeble 3800 at temperatures of 275, 300, and 350 °C with strain rates of 5 and 90 s − 1 up to 60 and 85% reduction. The microstructure and texture analysis were measured by using the EBSD technique on a large area. Experimental results show that the Cube component maintains a volume fraction between 10% and 20%, below the 40% recrystallization fraction, but the volume fraction of Cube significantly increases between 20% and 50% above the 40% recrystallization fraction. However, the fractions of Rotated Cube (RC) and Goss components remain below 10%. [ABSTRACT FROM AUTHOR]

Abstract The synthesis of nano-sized bimetallic Cobalt/Nickel oxides (Ni1.5Co1.5O4) with a 1:1 Co/Ni atomic ratio has been achieved using a surfactant-free co-precipitation/hydrothermal process. The growth mechanism of Cobalt/Nickel oxides Ni1.5Co1.5O4 is elucidated by tuning the synthesis process parameters, including co-precipitation pH and hydrothermal time. The formation of Cobalt/Nickel oxides Ni1.5Co1.5O4 oxide began with the nucleation of cobalt nickel hydroxide nanoplates through the co-precipitation process, followed by dissolution-recrystallization, stacked hexagonal nano-flakes, and a flower-like microstructure. The electrochemical performances of the oxides were evaluated, with the largest surface area observed at pH 9 being the main factor for the best super-capacitive performance. As hydrothermal time increased, the structural directing growth forward, resulted in the formation of a nano-flower structure with a larger surface area. The as-prepared cobalt nickel oxide exhibited a maximum specific capacitance value of 525.5 F g-1 at a current density of 1 A g-1 and energy and power densities of 88.2 WhKg-1 and 606 WKg-1, respectively.

The occurrence of recrystallization will greatly decrease the service life of superalloy blades. The dynamic recrystallization of a Ni-based single crystal superalloy under supergravity stress and high temperature was studied. When tested at 950 °C, only one recrystallization layer is formed on the surface, whereas this changes to two recrystallization layers when tested at 1050 °C. The supergravity produces a stress gradient in the sample, and the nucleation and growth of the recrystallized grains increase with the stress at both temperatures. This work helps to recognize the recrystallization behavior of superalloy under service conditions.

Electrodeposited -oriented nanotwinned Cu (NT-Cu) films consist of micron-scale columnar grains and they are thermally stable up to 400 °C. By adding nanoscale equiaxed Cu grains at the bottom of the NT-Cu films, anisotropic large grain growth could be triggered below 200 °C. The grains grew over 50 μm in bonded Cu–Cu films with 5.7 μm thick. Two main factors are identified for the low thermal stability and large grain growth behavior. The grain refining and transition layer thickening are effective to lower the thermal stability of the NT-Cu and reduce the required temperature for recrystallization and grain growth in the NT-Cu film. By increasing the fine-grained layer and refining the grain size of the columnar twinned grains, anisotropic grain growth can occur at 150 °C. The low thermal stability NT-Cu can be employed to completely eliminate the bonding interface at low temperatures in Cu–Cu joints. However, when the fine-grained layer is thicker than a threshold value, normal grain takes place and the bonding interface remains. The mechanism of anisotropic large grain growth was also proposed.

Hot compression tests were used to examine the hot deformation behavior and of high-grade pipeline X80 steel at strain rates of 0.001–1 s−1 and temperatures of 950–1100 °C. Two approaches were used to model material flow curves. The first used the Zener-Hollomon parameter, Z, to show the impact of deformation temperature and strain rate on flow stress, using the Arrhenius constitutive equation. The second used a rule of mixture to represent the material's flow curve, considering work hardening and dynamic recrystallization flow stresses. The first method was accurate at low Z and low strains, while the second method accurately displayed peak stress, was suitable for large strains, and predicting flow curves at industrial strain rates. The microstructure of X80 steel exhibits strain rate dependence under hot deformation conditions, with finer and more equiaxed microstructures observed at higher strain rates. These findings align with processing map predictions for stable deformation behavior, suggesting potential for optimized hot working processes. The static recrystallization kinetics showed that the Avarmi exponent, n, ranges from 1 to 2 for strains of 0.2 and 0.35 at 950 °C, but higher values were observed under hot deformation conditions.

To explore the effect of micro-Zr alloying on the hot deformation microstructure of 6082 aluminum alloy and its subsequent recrystallization during heat treatment， the hot deformation behavior and micro-orientation evolution of 6082 aluminum alloy containing Zr at different strain rates （0.01，1 s-1） were comparatively studied. The evolution process of grain structure before and after heat treatment was analyzed， and the regulatory effect of Zr addition on the thermally deformed sub-grains and recrystallization of 6082 aluminum alloy was further discussed. The results show that the addition of Zr makes the recrystallization of 6082 aluminum alloy during the hot deformation process mainly perform discontinuous dynamic recrystallization， and the recrystallization generated by the particle stimulated nucleation（PSN）mechanism also occurs， and minor Zr addition also plays a role in inhibiting recrystallization in the hot deformation process. After the micro-Zr alloying， the subgrain size decreases， the dislocation density increases， the recrystallization level decreases， and the recrystallization level of the sample at a higher strain rate is lower， and the addition of Zr promotes the generation of the discontinuous dynamic recrystallization of 6082 aluminum alloy during hot deformation.

Abstract Basalt-hosted monocentric agates from Bou Hamza (Morocco) were examined to unravel a discrete relationship between moganite content, water content, and the abundance of various types of chalcedony/quartz microtextures, so that the agate-forming process is refined. Herein, moganite content is noticeably low in length-slow chalcedony (quartzine, up to 18 wt.%), as compared with the co-occurring length-fast (LF) chalcedony (up to 31 wt.%). Such a type of disparity reflects a stabilization of the crystallization front during the formation of chalcedonic bands. Recrystallization-related quartz types (i.e. feathery and mosaic/jigsaw puzzle) show low and high moganite content (0 and up to 34 wt.%, respectively) since they have likely originated from different silica precursors (i.e. opaline and chalcedonic, respectively). Meanwhile, the initial formation of mosaic quartz can be exclusively witnessed in the so-called zebraic variety of length-fast chalcedony (i.e. with twisted fibres) that should be hence regarded as a ,,metastable” variety of silica though. The range of total water content remains quite stable across chalcedonic bands (0.5–0.6 wt%) and reaches the highest values (0.7 wt%) in feathery quartz. However, there is rather a general negative relationship between the content of molecular water and silanol-group water. This can stem from the recycling of water species following the condensation reaction of silanols within the agate geodes. The agates originated from Fe-Ti-bearing solutions that co-precipitated goethite, hematite, and rutile, but also contain minor low-grade carbonaceous material.

A novel strategy involving warm rolling and tempering-annealing was introduced to optimize the strength-ductility balance of Fe-10.2Mn-2.2Al-0.41C-0.6 V (wt. %) steel. The V- and κ-carbide particles produced during the tempering are critical for tailoring the austenite characteristics during the subsequent annealing. Austenite that nucleates on Mn-rich κ-carbides inherit their high Mn content and fine grain size. Quantitative calculations suggest that the pinning effect exerted by the V-carbide particles strongly resists grain boundary motion and recrystallization grain growth, further refining the final microstructure. Moreover, the dual nano-sized particles induce abnormal variations in the grain size and fraction of austenite, influencing the deformation mechanisms. In the absence of deformation twins, the fresh martensite develops into “separating walls” to refine the microstructure and further enhances the work hardening in addition to the complex dislocation mobile. Finally, the tempered-annealed sample demonstrated a simultaneous increase in the yield and tensile strengths from 1166 to 1452 MPa and 1507–1727 MPa, but a slight decrease in the total elongation from 18.6% to 16.8% compared to annealed sample, achieving a good strength-ductility balance.

Ionizing events having a wide variety of radiation‐induced effects can radically affect the kinetics of defect production or structural transformation in the pyrochlore structured oxides (A2B2O7). Therefore, a thorough understanding of the kinetics associated with cation ordering and disordering is required for various technological applications. The structural responses of Gd2Ti2‐yZryO7 (y = 0.4, 1.2, 1.6) pyrochlore series irradiated by 120 MeV Au9+ ions were investigated using in situ synchrotron x‐ray diffraction (SR‐XRD), micro‐Raman spectroscopy, and scanning electron microscopy (SEM). Each pyrochlore composition irradiated at the highest fluence, where structural modifications occur, was subsequently isochronally annealed from room temperature to 1000°C. The SR‐XRD results indicate that Ti‐rich composition (y = 0.4) retains its pre‐irradiated pyrochlore structure (Fd3¯$\bar{3}$m) at 1000°C. In contrast, Zr‐rich compositions exhibit recrystallization to an intermediate defect‐fluorite phase (Fm3¯$\bar{3}$m) above 500°C, and the pre‐irradiated pyrochlore superstructure does not recover even on annealing at 1000°C. These results reveal that recrystallization temperature strongly depends on the accumulated radiation damage, generally described with the cationic radius ratio (rA/rB). Thus, investigation of the thermal annealing behavior of irradiated pyrochlores helps better understanding the general mechanisms of radiation damage and recovery of pyrochlores, which is important for their use in nuclear applications. [ABSTRACT FROM AUTHOR]

This study investigated the influence of the addition of Al to a Mg–7Bi (B7, wt%) alloy, particularly its recrystallization behavior during extrusion and its resulting mechanical properties. The addition of 2 wt% Al to the B7 alloy resulted in a lower grain size, a reduction in the number density of fine Mg3Bi2 particles, and a higher area fraction of relatively coarse Mg3Bi2 particles in the extrusion billet. These microstructural changes increased the nucleation sites for recrystallization, reduced the Zener pinning effect, and enhanced particle-stimulated nucleation, all of which promoted dynamic recrystallization behavior during extrusion. As a result, the area fraction of recrystallized grains in the extruded alloy increased from 77 % to 94 %. The extruded B7 alloy exhibited a strong fiber texture, whereas the extruded Mg–7Bi–2Al (BA72) alloy had a weak – texture, which was attributed to the minimal presence of unrecrystallized grains and the dispersed orientation of the recrystallized grains. The tensile yield strength (TYS) of the extruded BA72 alloy was higher than that of the extruded B7 alloy (170 and 124 MPa, respectively), which resulted from the enhanced grain-boundary and solid-solution strengthening effects. The tensile elongation (EL) of the BA72 alloy also exceeded that of the B7 alloy (20.3 % and 6.1 %, respectively), the result of the uniform formation of fine twins under tension in the former and the formation of a few coarse twins among the unrecrystallized grains in the latter. Consequently, the addition of a small amount of Al to the B7 alloy significantly improved both the strength and ductility of the extruded alloy, resulting in a remarkable increase in the product of the TYS and EL from 756 to 3451 MPa% and expanding its potential range of applications as a lightweight extruded structural component.

To explore the variances between single-reinforced and hybrid-reinforced Al–Mg–Si alloys with TiC and B4C, 10 wt.%-(TiC + B4C)/6061Al, 10 wt.%-B4C/6061Al, 10 wt.%-TiC/6061Al and 6061Al were prepared via wet mixing for 8 h followed by vacuum hot-press sintering at 580 °C and 30 MPa for 2 h. Microstructure evolution, mechanical properties, and wear behavior were investigated in this study. The results show that unlike single reinforcement of TiC, single reinforcement of B4C and hybrid reinforcement of TiC and B4C altered the distribution of Si and facilitated the in-situ formation of SiC. Both single reinforcement and hybrid reinforcement resulted in mixed fracture characteristics of ductile fracture and cleavage fracture, while hybrid reinforcement of TiC and B4C demonstrated superior strength and plasticity matching. At equivalent particle mass fractions, single reinforcement of TiC was more conducive to inducing recrystallization during sintering, followed by single reinforcement of B4C, and hybrid reinforcement of TiC and B4C had the least effect. At equivalent particle mass fractions, single reinforcement of B4C had the most significant effect on improving the wear resistance, followed by hybrid reinforcement of TiC and B4C, and single reinforcement of TiC had the least effect. All particle addition methods demonstrated a mixed wear mechanism involving abrasive wear, adhesive wear, and spalling wear. This study provides valuable insights into the development of aluminum matrix composites.

This study investigated the effects of electropulsing treatment (EPT) condition on the microstructure and microhardness of cold-rolled Grade 2 Ti sheet. Particular attention was paid to the dependence of the material properties on the electric current direction, referred to as electropulsing anisotropy. Direct-current (DC) EPT was applied along either the rolling direction (RD) or transverse direction (TD) of the rolled sheet. EPT along the TD resulted in a higher heating rate and maximum temperature, whereas that along the RD accelerated the static recrystallization (SRX) process under identical electropulsing parameters. Such a discrepancy was interpreted using the elongated grain structure and basal texture in the cold-rolled Ti sheet. These results were further supported by microhardness measurements, confirming the presence of electropulsing anisotropy during DC EPT in Ti alloys for the first time. In addition, the employed EPT was compared to a traditional furnace heat treatment (FHT) with rigorous temperature and time control, wherein the optimum EPT process spent only 13% of the processing time to complete SRX with a lower thermal energy requirement. This indicates a significant athermal contribution of EPT to electropulsing anisotropy.

Abstract Cryogenic treatment has high potential for improving the deformation behavior through the recrystallization at a low temperature. In this work, true stress–strain curves were obtained via compression tests to understand the deformation behavior of an AA7075 under cryogenic conditions. Results showed a significant improvement in the flow stress of AA7075, increasing from 260 to 560 MPa at the yield point. The strain hardening exponent (n) also increased from 0.25 to 0.35 after deformation at cryogenic temperatures. The presence of Al2CuMg phase influenced the deformation texture of the tested aluminum alloy, resulting in more elongated grains and fine sub-grains after deformation at cryogenic temperatures, due to the hindered recrystallization. Microstructure evolution after deformation at room and cryogenic temperatures was investigated using EBSD technique to characterize texture and recrystallized grains. The results indicated that the spacing of the high-angle grain boundaries (HAGBs) in the sample deformed at room temperature was slightly larger than in the cryogenically treated sample. The alloy deformed at the cryogenic temperature exhibited a higher strain hardening exponent (n = 0.35) compared to room temperature deformation (n = 0.25). Furthermore, finite element analysis supported the experimental findings, showing that the Plastic Equivalent Strain (PEEQ) of the model tested at cryogenic temperature was higher than at room temperature, attributed to grain refinement during low-temperature deformation. The calculated effective stress responses at cryogenic temperatures for the investigated flow stress aligned well with the experimental results. These new aspects and mechanisms of deformation of aluminum alloys at cryogenic temperatures can improve the formability of high-strength alloys in the future production of more complex and integrated lightweight components.

The effect of initial grain size prior to cold rolling on the microstructure, texture evolution, and magnetic properties of Fe-3.5 wt% Si non-oriented electrical steel (NOES) was investigated through the introduction of normalization. There were massive intragranular shear bands in {111} and {111} deformed grains in the cold-rolled sheet with large initial grain size, providing nucleation sites for new recrystallized grains with Goss ({110}), λ-fiber, γ-fiber, and {113} components. Subsequent annealing resulted in weaker γ-fiber ({111}−{111}), stronger α*-fiber concentrated at {113}, along with Goss and λ-fiber ({100}−{100}) textures. In addition, appropriate final annealing temperature effectively reduced iron loss. The simultaneous optimization of texture and grain size by normalization and annealing treatments led to improved magnetic properties, with the superior magnetic induction (B50 = 1.719) T, and the lowest core loss (P15/50 = 2.69 W/kg, P10/400 = 16.337 W/kg).

Using undercooling technology combined with melt purification of glass and recirculation overheating, different undercoolings were successfully obtained for Cu60Ni38Co2 alloy samples. Applying high speed photography technique, the physical process of undercooled solidification was observed and relationship between undercooling and solidification rate was analyzed. Experimental results indicate the critical undercoolings exist in the structure evolution process. Electron backscatter diffraction (EBSD) analysis was applied to characterize the Cu60Ni38Co2 alloy sample with a maximum undercooling of 255K, revealing grain orientation and the corresponding orientation difference distribution. In addition, transmission electron microscopy (TEM) showed high density dislocation networks. Combining EBSD and TEM data analysis, an important conclusion was drawn: recrystallization is the main factor for grain refinement at high undercooling. This finding is of great significance for a deeper understanding of the structure evolution in the physical process of undercooled alloys.

Purpose. The study is aimed at evaluating the effect of the isothermal transformation temperature on the structure and properties of low-carbon steel. Methodology. The material for the study was a 3 mm diameter wire made of mild steel with the following chemical composition: 0.21% C, 0.47% Mn, 1.2% Si, 0.1% Cr, 0.03% S, 0.012% P. The 0.3 m long wire samples were subjected to austenitizing at 920 °C for 8...9 min, after which they were held isothermally for 11 min at temperatures of 650...200 °C, followed by cooling in air. The strength, plastic properties, and strain hardening coefficient were determined from the analysis of tensile curves. Findings. It was found that a decrease in the temperature of isothermal transformation, starting from 450...400 °C, increases the amount of Widmannstätten ferrite due to the disappearance of polyhedral ferrite grains. At the same time, the number of areas with locally located dispersed cementite particles similar to pearlite colonies increases, and bainite crystals appear. Against the background of a sharp decrease in the strain hardening coefficient in the range of 450...400 °C, the ability of the bainite phase to undergo plastic deformation should be considered one of the reasons for the delay in density reduction. Originality. The effect of steel hardening with a decrease in the pearlite transformation temperature is based on the grinding of ferrite grains, an increase in the amount of Widmannstätten ferrite, and the dispersion of pearlite colonies. The strengthening effect of steel with a bainite structure is based on an increase in the degree of supersaturation of the solid solution with carbon atoms and dispersion hardening by particles of the carbide phase. Practical value. The optimal structural state of steel intended for the manufacture of such critical elements as a support beam, railroad car bogie, etc. is a mixture of phase components with different dispersion and morphology, and their quantitative ratio is determined by the operating conditions of a particular product.

Oscillating laser-arc hybrid welding of AZ31B magnesium alloy was carried out, the effects of beam oscillation parameters on pore inhibition, microstructure, grain boundary characteristics and tensile properties were investigated. The results showed that the pore formation can be inhibited with oscillating frequency higher than 75 Hz and radius smaller than 0.5 mm. The columnar grains neighboring the fusion line can be broken by the beam oscillation behavior, while the grain growth was promoted with the increase of frequency or radius. It should be noted that the coincidence site lattice (CSL) boundaries were mainly Σ13b and Σ29 boundaries, which were contributed by {101¯2} tensile twins and {112¯2} compression twins, respectively. The total fraction of CSL boundaries reached maximum at radius of 0.25 mm and frequency of 75 Hz, which was also confirmed as the optimized parameters. In this case, the elongation rate increased up to 13.2%, 12.8% higher than that of the weld without beam oscillation. Finally, the pore formation and inhibition mechanisms were illustrated according to the state of melt flow and keyhole formation, the abnormal growth was discussed basing on secondary recrystallization, and the relationship among the pore formation, grain size, boundary characteristics and weld toughness were finally established.

Twinning is widely recognized as an effective and cost-efficient method for controlling the microstructure and properties of wrought magnesium (Mg) alloys. Specifically, twins play a crucial role in initiating dynamic recrystallization (DRX), while twin regions experience rapid recrystallization during static recrystallization (SRX). The activation of twinning can lead to changes in lattice orientation, significantly impacting the final texture in Mg alloys. The active roles of twinning are influenced by various factors during the activation process, and the mobility of twin boundaries (TB) can be amplified by stress effects, dislocation interactions, and thermal effects. Conversely, annealing treatments that involve proper segregation or precipitation on TBs serve to stabilize them, restraining their motion. Events such as segregation may also alter the twinning propensity in Magnesium-rare earth (Mg-RE) alloys. While {10–11} contraction twins (CT) and {10–11}-{10–12} double twins (DT) can promote dynamic recrystallization (DRX), they also pose a risk as potential sources of voids and cracks. Additionally, understanding the nucleation and growth mechanisms of twinning is crucial, and these aspects are briefly reviewed in this article. Considering the factors mentioned above, this article summarizes the recent research progress in this field, shedding light on advancements in recent eras.

A melting failure of W monoblock components of the upper divertor outer target in EAST occurred during the plasma campaigns in 2019. The failure characters and microstructure evolution of the failed W monoblock have been well investigated on one string (W436 string). Near the strike point region where heat flux density is highest, macroscopic cracks and severe surface damage such as dimensional change, melting and solidification are visible in several W monoblocks. At the same time, debonding, melting and migration of Cu/CuCrZr cooling tube components introduced fatal damage to the structure and function. The heat-induced microstructure evolution in the rest part has been examined via hardness tests and metallography. From the heat flux surface to the cooling tube, hardness increased gradually and the recrystallized grains could be found in the region with the highest temperature, while recrystallization grains also appear in some W monoblocks near the cooling tube area. The detailed microstructure has been investigated by metallography and EBSD. Such cases in EAST provide experiences on the extreme condition of accidental loss of coolant or higher discharge power in future devices.

This paper examines the relationship between the magnetization behavior and crystal lattice orientations of Fe–Si alloys intended for magnetic applications. A novel approach is introduced to assess anisotropy of the magnetic losses and first magnetization curves. This method links the magnetocrystalline anisotropy energy of single crystal structures to the textures of polycrystalline materials through a vectorial space description of the crystal unit cell, incorporating vectors for external applied field and saturation magnetization. This study provides a preliminary understanding of how texture influences magnetic loss rates and the first magnetization curves. Experimental results from Electron Back-Scattered Diffraction (EBSD) and Single-Sheet Tests (SSTs), combined with energy considerations and mathematical modeling, reveal the following key findings: (i) a higher density of cubic texture components, whether aligned or rotated relative to the rolling direction, decreases magnetic anisotropy, suggesting that optimizing cubic texture can enhance material performance; (ii) at high magnetic fields, there is no straightforward correlation between energy losses and polarization; and (iii) magnetization rates significantly impact magnetization loss rates, highlighting the importance of considering these rates in optimizing Fe–Si sheet manufacturing processes. These findings offer valuable insights for improving the manufacturing and performance of Fe–Si sheets, emphasizing the need for further exploration of texture effects on magnetic behavior. [ABSTRACT FROM AUTHOR]

In order to identify relations between mechanical behavior, deformation mechanisms, microstructural properties, and H2O distribution, Tana‐quartzite samples with added H2O ranging from 0 to 0.5 wt.% were deformed by axial shortening at constant displacement rates, at 900°C and 1 GPa, reaching up to ∼30% bulk strain. Samples with lower quantities of added H2O (0.1 and 0.2 wt.%) were in average ∼30 MPa weaker than the as‐is samples with no added H2O. In contrast, samples with more than 0.2 wt.% added H2O revealed more variable mechanical behavior, showing either weaker or stronger trend. The weaker samples showed strain localization in their central parts in the vicinity of the thermocouple, that is, the hottest parts of the samples, whereas the stronger samples showed localization in their upper, slightly colder parts. Bulk deformation is accommodated by crystal plasticity and dissolution‐precipitation processes. Distribution of H2O in our samples revealed systematic decrease of H2O content in the interiors of original grains, caused by increasing strain and H2O draining into grain boundary regions. With increasing content of added H2O, the quartz recrystallization gradually changes from subgrain‐rotation‐dominated to crack‐induced nucleation, along with increasing quantity of melt/fluid pockets. The unexpected strain localization in the upper parts of stronger samples most likely results from mode‐1‐cracking that led to drainage of grain boundaries (GB) due to the crack dilatancy effect, and inhibited dissolution‐precipitation in the hottest part of the samples next to the thermocouple. The locus of deformation is then shifted to colder regions where more H2O is available along GB. Plain Language Summary: The mechanical behavior of rocks is reflected by deformation microstructures, and it is usually dependent on available H2O in the deformation environment. We tested influence of H2O in quartzite samples by adding various amounts of H2O prior to deformation experiments, in the range from 0 to 0.5 wt.%. The results showed that samples with up to 0.2 wt.% of added H2O are generally weaker than the as‐is samples, while with H2O addition of more than 0.2 wt.% mechanical behavior becomes more erratic. These samples showed either weaker or stronger behavior. While plastic deformation in weaker samples is localized mostly in sample regions with the highest temperature, deformation in stronger samples is unexpectedly localized in colder regions. Quartz grains are found to release initially present H2O from their interiors into grain boundary regions during deformation. Changes in mechanical properties with increasing content of H2O are closely related with changes in recrystallization processes. The unexpected localization of deformation in the colder regions results from drainage of GB due to the crack dilatancy effect. In the resulting dried GB, the dissolution‐precipitation processes would be impeded, while the locus of deformation is shifted to colder parts with more H2O along the GB. Key Points: H2O initially present inside the quartz grains is transferred into grain boundary region during heating, pressurization, and deformationA quantity of added H2O of >0.2 wt.% causes more variable mechanical behavior of the samples due to enhanced crackingDilatant cracks lead to draining of fluid from grain boundaries and make the dissolution‐precipitation processes locally less efficient [ABSTRACT FROM AUTHOR]

Prolonging the lifetime of SAPO‐34 catalysts and enhancing their olefin selectivity in methanol‐to‐olefin (MTO) reactions are critical yet challenging objectives. Here, a series of hierarchical SAPO‐34 catalysts were synthesized using a straightforward recrystallization method. The incorporation of triethylamine into the recrystallization mother liquor facilitated the formation of mesopores, achieving a high solid yield of up to 90%. Notably, the addition of phosphoric acid and ammonium polyvinyl phosphate alcohol during the recrystallization process significantly enhanced the crystallinity and regularity of the hierarchical SAPO‐34 crystals, consequently increasing the mesopore size. Due to the substantially improved mass transfer efficiency and moderated acidity, the SP34‐0.14P‐0.06R catalysts exhibited a prolonged lifetime of 344 min and 80.3% selectivity for ethylene and propylene at a weight hourly space velocity (WHSV) of 2 h−1. This performance markedly surpasses that of the parent SP34 catalyst, which demonstrated a lifetime of 136 min and a selectivity of 78.0%. Remarkably, the SP34‐0.14P‐0.06R maintained a lifetime of 166 min even at a high WHSV of 10 h−1, which is more than 5‐fold greater than that of the original microporous SP34. This research offers valuable insights into the design and development of hierarchically porous zeolites with high yields, enhancing the efficiency of MTO reactions and other applications. [ABSTRACT FROM AUTHOR]

The effect of acid treatment on TS-1 zeolite prior to alkaline treatment with TPAOH solution is investigated. 1H MAS NMR, UV–Vis, XPS, XRF, N2-sorption and TEM are applied to characterize the acid and/or alkaline treated TS-1 samples. It is found that acid treatment destructs the Si–O-Ti bonds of the framework, and promotes the conversion of 4-coordinated Ti into 6-coordinated Ti. Then in the subsequent alkaline treatment, part of framework Si–O-Si bonds are hydrolyzed and mesopores are formed. Meanwhile, the dissolved Si and Ti species could be incorporated back into the framework directed by TPAOH. Compared with TS-1-A, which is synthesized without acid treatment, TS-1-HA remains more active center and enhanced accessibility. Therefore, it shows high catalytic performance in cyclohexanone ammoximation reaction. [ABSTRACT FROM AUTHOR]