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This study demonstrated the unique crystallographic features in Al 2 O 3 /YAG eutectic by seed-crystal inducing in laser floating zone melting (LFZM) process for crystallographic orientation control. The as-fabricated eutectic ceramics induced by different single crystalline seeds were mainly composed of randomly oriented Al 2 O 3 faceted particles and irregular eutectic, as a result of the initial uncoupled growth at the junction of seed and eutectic. Specifically, along the direction of directional solidification, the eutectic ceramics grew stably with a single crystallographic orientation relationship with low planar disregistry (2 %∼6 %). The stability of phase interface with minimum interfacial strain and better ionic charge balance in Al 2 O 3 /YAG eutectic has a greater effect on the regulation of the eutectic growth orientation than the constraint of the single crystalline seed. [ABSTRACT FROM AUTHOR]

Energy‐dispersive Laue diffraction (EDLD) is a powerful method to obtain position‐resolved texture information in inhomogeneous biological samples without the need for sample rotation. This study employs EDLD texture scanning to investigate the impact of two salivary peptides, statherin (STN) and histatin‐1 (HTN) 21 N‐terminal peptides (STN21 and HTN21), on the crystallographic structure of dental enamel. These proteins are known to play crucial roles in dental caries progression. Three healthy incisors were randomly assigned to three groups: artificially demineralized, demineralized after HTN21 peptide pre‐treatment and demineralized after STN21 peptide pre‐treatment. To understand the micro‐scale structure of the enamel, each specimen was scanned from the enamel surface to a depth of 250 µm using microbeam EDLD. Via the use of a white beam and a pixelated detector, where each pixel functions as a spectrometer, pole figures were obtained in a single exposure at each measurement point. The results revealed distinct orientations of hydroxyapatite crystallites and notable texture variation in the peptide‐treated demineralized samples compared with the demineralized control. Specifically, the peptide‐treated demineralized samples exhibited up to three orientation populations, in contrast to the demineralized control which displayed only a single orientation population. The texture index of the demineralized control (2.00 ± 0.21) was found to be lower than that of either the STN21 (2.32 ± 0.20) or the HTN21 (2.90 ± 0.46) treated samples. Hence, texture scanning with EDLD gives new insights into dental enamel crystallite orientation and links the present understanding of enamel demineralization to the underlying crystalline texture. For the first time, the feasibility of EDLD texture measurements for quantitative texture evaluation in demineralized dental enamel samples is demonstrated. [ABSTRACT FROM AUTHOR]

In this study, we investigated the microstructural evolution of a Cu-0.13Sn-0.04Mg alloy that underwent heat treatment followed by room temperature rolling (RTR). Initially heat-treated specimens were rolled at room temperature (RT) with reduction ratios (RR) of 40% and 75% to perform microstructural and crystallographic textural analyses. Electron backscattered diffraction (EBSD) and transmission electron microscopy (TEM) were utilise to examine both initial and deformed microstructures. Both exhibited heterogeneous microstructural distributions. Shear bands (SBs) existed in the initial specimen and became main sites for the nucleation of new grains during heat treatment. A denser presence of SBs was noted in the RTR specimens. Remarkably, an unusual self-annealing phenomenon was observed in these specimens, culminating in the emergence of recrystallized grains at RT. A plethora of such grains was observed in the severely deformed specimens, with numerous nucleating grains appearing proximal to the SBs or deformed grain boundaries (GBs). Time dependent microstructure evolution was observed via ex-situ EBSD technique in the compressed specimens. Formation of new grains, increase in high angle grain boundaries (HAGBs), and dislocation annihilations were observed with the progress of time. The crystallographic texture evolution in the initial specimen was predominantly influenced by the S component. At lower strains, the fractions of Copper component increased, whereas at higher strains, a greater fraction of Brass and S components were induced. Following a 40% RR, a saturation in hardness value was observed, which could be potentially attributable to an accelerated rate of RT recrystallization in the case of 75% RR. [ABSTRACT FROM AUTHOR]

In the multilayer thin-walled Inconel 625 alloy structures fabricated by the laser additive manufacturing (LAM) process, the poor plasticity of the interlaminar region often leads to structural fractures. In this paper, an oscillating LAM (O-LAM) technology using a transverse linear beam oscillation (LBO) process was proposed, and the effect of laser scanning speed on the forming accuracy, microstructure, crystallographic texture, and mechanical properties of interlaminar region was studied. The results show that the LBO process refined the grains and increased the number and length of high-angle grain boundaries in the interlaminar region. In addition, the LBO process with high laser scanning speed weakened the preferential orientation along the directions of laser scanning and deposition build-up. In particular, the dominant crystallographic textures of { 1 ¯ 10 } < 1 ¯ 1 ¯ 1 > and { 2 ¯ 21 } < 1 ¯ 1 ¯ 0 > in the interlaminar region were significantly reduced. The analysis of the Schmidt factor and the results of nano-indentation test show that the LBO process with high laser scanning speed reduced the stress concentration, and the elastic modulus and dislocation density in the interlaminar region. Therefore, the LBO process with high laser scanning speed can improve the plasticity and relieve the stress concentration of the interlaminar region, which is conducive to improving the overall mechanical properties of the Inconel 625 alloy multilayer thin-walled structure. [ABSTRACT FROM AUTHOR]

The additive manufacturing of directionally solidified Ni-based superalloys remains a significant challenge due to the formation of stray equiaxed grains and their high susceptibility to cracking, particularly for high-volume γ´-type Ni-based superalloys. In this study, a novel strategy based on temperature field management was proposed to prevent hot cracking and control crystallographic texture during laser powder bed fusion (LPBF) of IN738LC superalloy. The influence of laser parameters and substrate preheating on crack density, melt pool morphology, and texture of IN738LC superalloy was investigated. The fluid dynamics and thermal behavior of melt pool was simulated using the discrete element model (DEM) and volume of fluid (VOF) method. The processing window for achieving defect-free IN738LC samples was established and was found to be highly affected by substrate preheating. Substrate preheating at 350 °C resulted in expanded processing window, with the volume energy density ranging from 42.9 to 62.5 J/mm³ without substrate preheating to 40–75 J/mm³. The enlarged processing window was achieved by reducing cracking susceptibility due to the reduced temperature gradient and cooling rate. A unique crystallographic lamellar microstructure (CLM), comprising a -oriented major layer and -oriented sub-layer along the building direction, was successfully achieved in the LPBF-processed IN738LC superalloy. The solidification conditions for obtaining such a CLM were discussed on the aspects of temperature gradient and solidification rate within the melt pool. This work provides new insights and methods for preparing crack-free γ´-Ni-based superalloys with specific textures, which is favorable for improving the high-temperature properties.

The paper covers the production, analysis of the microstructure, crystallographic texture and deformation mechanisms of the ultrafine-grained (UFG) Zn–1%Mg–1%Fe zinc alloy demonstrating unique physical and mechanical properties compared to its coarse-grained analogues. The zinc alloy with improved mechanical properties was developed in two stages. At the first stage, based on the analysis of literature data, an alloy with the following chemical composition was cast: Zn–1%Mg–1%Fe. Then, the alloy was subjected to high-pressure torsion (HPT) to improve mechanical properties, due to grain structure refinement, and implementation of dynamic strain aging. The conducted mechanical tensile tests of the samples and assessment of the alloy hardness, showed that HPT treatment leads to an increase in its tensile strength to 415 MPa, an increase in hardness to 144 HV, and an increase in ductility to 82 %. The obtained mechanical characteristics demonstrate the suitability of using the developed alloy in medicine, as some implants (stents) requiring high applied loads. To explain the reasons for the improvement of the mechanical properties of this alloy, the authors carried out comprehensive tests using microscopy and X-ray diffraction analysis. The microstructure analysis showed that during the formation of the ultrafine-grained structure, a phase transition is implemented according to the following scheme: Zneutectic + Mg2Zn11eutectic + FeZn13 → Znphase + Mg2Zn11phase + MgZn2particles + Znparticles. It was found that as a result of high pressure torsion in the main phases (Zn, Mg2Zn11), the grain structure is refined, the density of introduced defects increases, and a developed crystallographic texture consisting of basic, pyramidal, prismatic, and twin texture components is formed. The study showed that the stability of pyramidal, prismatic and twin texture components at the initial stages of high-pressure torsion, determines the level and anisotropy of the strength properties of this alloy. The relationship between the discovered structural features of the produced alloy and its unique mechanical properties is discussed.

Depending on the 3D-printing orientation, the anisotropy of the elastic characteristics of the Inconel 625 alloy generated with selective laser sintering from powders is investigated. The impact of the original powder combination and the following heat treatment (post-printing treatment) on the anisotropy of the alloy elastic characteristics is assessed. As demonstrated, the suggested treatments can lessen the anisotropy of the alloy elastic characteristics. Based on knowledge of the elastic constants of the single crystal and x-ray texture features, the results of a theoretical estimation of the elastic and shear moduli, Poisson’s ratio, and their anisotropy in the horizontal and vertical directions of 3D printing are provided. As demonstrated, the obtained theoretical values differ by 6–10% from the corresponding experimental values. The calculated stress–strain state can be more accurately calculated with the use of the estimated elastic characteristics and their anisotropy. The strategy for 3D-printing complicated components from Inconel 625 alloy may be made more effective.

In this study, we present a systematic analysis of the relation between the structural properties and magnetic anisotropies of as-grown and heat-treated polycrystalline Fe 1 − x Ga x (0.11 < x < 0.19) thin films deposited on glass and Si(100) substrates. The results show that the crystallographic texture of the films has a significant impact on the evolution of the magnetic anisotropies. The samples grown on glass do not exhibit a preferred texture while, for samples grown on Si(100), the appearance of a weak in-plane fourfold magnetic anisotropy is reported. Such anisotropy is enhanced and better defined in the heat treated samples. Via a phenomenological model we show that this anisotropy has a microstructural origin. These findings demonstrate the possibility of tuning magnetic anisotropies by growing on different substrates and/or performing thermal treatments, which in turn reinforces the possibility of developing smart magnetic switching materials for electronic applications. [ABSTRACT FROM AUTHOR]

Rotation axes (together with rotation angles) are often used to describe crystal orientations and misorientations, and they are also needed to characterize some properties of crystalline materials. Since experimental orientation data are subject to errors, the directions of the axes obtained from such data are also inaccurate. A natural question arises: given the resolution of input rotations, what is the average error of the rotation axes? Assuming that rotation data characterized by a rotation angle ω deviate from the actual data by error rotations with fixed angle δ but which are otherwise random, the average error of the rotation axes of the data is expressed analytically as a function of ω and δ. A scheme for using this formula in practical cases when rotation errors δ follow the von Mises–Fisher distribution is also described. Finally, the impact of crystal symmetry on the determination of the average errors of the axis directions is discussed. The presented results are important for assessing the reliability of rotation axes in studies where the directions of crystal rotations play a role, e.g. in identifying deformation slip mechanisms. [ABSTRACT FROM AUTHOR]

In the present study, Stainless steel 316L (SS316L) cylindrical specimens were fabricated at two different build orientations and two different laser powers using Laser powder bed fusion process (LPBF). Microstructural characterization such as XRD, SEM, EBSD analysis and tensile testing were carried out on fabricated specimens in stress relieved condition to understand the anisotropic behavior of LPBF printed specimens. Horizontally oriented specimens showed higher tensile strength when compared to vertically oriented specimens for both laser powers. XRD and EBSD phase maps did not reveal the presence of any secondary phases. However, build orientation and laser power affected the crystallite size of the samples. Bimodal grain structure comprising coarse columnar grains and fine equiaxed grains were observed from the micrographs. With variation in build orientation, there was a significant change in the average grain size of the specimens. High dislocation density was observed in horizontally oriented samples built at low laser power because of dislocation annihilation that can occur at high temperatures. However, EBSD analysis revealed random weak crystallographic texture which does not vary significantly with laser power or build orientation. Variation in grain size, grain morphology, sub-grain features and dislocation density are the reasons for the anisotropic tensile behavior observed in LPBF printed SS316L coupons in stress relieved condition. [ABSTRACT FROM AUTHOR]

The influence of the friction stir process (FSP) on the hole expansion formability of dual-phase 600 steel was examined by experimental and finite element analyses. Due to the microstructure of refining ferrite, martensite, and bainite, the yield strength and tensile strength increased after FSP by 95% and 63%, respectively. FSP led to the formation of (101) || ND and (111) || RD texture components in the processed zone. The observation of (111) || RD texture components in the FSPed steel resulted in an increment in the plastic strain ratio from 0.86 to 0.98. FSP provided a 20% improvement in the hole expansion ratio. The microstructural refinement and crystallographic texture played an important role in this increase. The FSP contributed to the increase in the hole expansion formability capability by delaying the crack formation during hole expansion and by causing the hole to fail at a higher load. It has been observed by experimental and finite element (FE) simulation results that the highest circumferential stress occurs at the hole edge where the main crack is formed. The FE simulation predictions agree with less than 2% error with the experimental observations. [ABSTRACT FROM AUTHOR]

A dual-functional ionic liquid additive, 1-butyl-3-methylimidazolium hydrogen sulfate (BMIHSO 4), is developed to tune the preferential Zn(002) crystallographic texture and simultaneously suppress the hydroxide sulfate accumulation on Zn anode by dynamically manipulating electrolyte pH-surroundings. The effective suppression of Zn dendrite growth enables a Zn symmetrical cell cycling stably to over one year. [Display omitted] Zn anodes suffer from the formation of uncontrolled dendrites aggravated by the uneven electric field and the insulating by-product accumulation in aqueous zinc-ion batteries (AZIBs). Here, an effective strategy implemented by 1-butyl-3-methylimidazolium hydrogen sulfate (BMIHSO 4) additive is proposed to synergistically tune the crystallographic orientation of zinc deposition and suppress the formation of zinc hydroxide sulfate for enhancing the reversibility on Zn anode surface. As a competing cation, BMI+ is proved to preferably adsorb on Zn-electrode compared with H 2 O molecules, which shields the "tip effect" and inhibits the Zn-deposition agglomerations to inducing the horizontal growth along Zn (002) crystallographic texture. Simultaneously, the protonated BMIHSO 4 additives could remove the detrimental OH– in real-time to fundamentally eliminate the accumulation of 6Zn(OH) 2 ·ZnSO 4 ·4H 2 O and Zn 4 SO 4 (OH) 6 ·H 2 O on Zn anode surface. Consequently, Zn anode exhibits an ultra-long cycling stability of one year (8762 h) at 0.2 mA cm−2/0.2 mAh cm−2, 3600 h at 2 mA cm−2/2 mAh cm−2 with a high plating cumulative capacity of 3.6 Ah cm−2, and a high average Coulombic efficiency of 99.6 % throughout 1000 cycles. This work of regulating Zn deposition texture combined with eliminating notorious by-products could offer a desirable way for stabilizing the Zn-anode/electrolyte interface in AZIBs. [ABSTRACT FROM AUTHOR]

Sm2Co14.75Fe1.5Ti0.75 nano-flakes have been prepared by surfactant-assisted ball milling (SABM) in the organic solvent of heptane with the surfactants of oleic acid. The effects of ball milling time on phase composition and magnetic properties were systematically studied. The experimental results show that the synthesized nano-flakes have an amorphous phase and a hexagonal 2:17-type crystalline phase with [00l] in-plane crystallographic texture induced by SABM without any external magnetic field. The coercivity value of the as-prepared nano-flakes was 5.0 kOe and then was enhanced to 6.0 kOe by the magnetic alignment for the sample ball-milled for 4 h. The remanence value of the un-aligned nano-flakes is lower than that of the magnetically aligned ones. In addition, the magnetically aligned nano-flakes exhibit a maximum energy product (BH)max of 56 kJ/m3 and a small misalignment angle θ of 11°, which is the best value ever reported. The magnetic anisotropy behavior was also observed in both aligned and un-aligned nano-flakes. [ABSTRACT FROM AUTHOR]

In classical texture analysis the orientation distribution function (ODF) is expanded as an infinite series of Wigner D -functions D m n l (⋅) , with the classical texture coefficients c m n l serving as undetermined expansion parameters. Herein we present a systematic procedure by which the classical expansion of an ODF (with arbitrary crystallite and texture symmetry) truncated at the order l = L can be directly rewritten as a tensorial Fourier expansion truncated at the same order, where the same set of classical texture coefficients c m n l appear as undetermined parameters. The crucial step of this procedure is as follows: Let H l be the complexified space of l -th order harmonic tensors and 〈 ⋅ , ⋅ 〉 the Hermitian inner product on H l . Let R be a rotation and R ⊗ l : H l → H l be the l -th order tensor product of R with itself. For each 1 ≤ l ≤ L , determine an orthonormal irreducible tensor basis B m l (− l ≤ m ≤ l) in H l so that D m n l (R) = 〈 B m l , R ⊗ l B n l 〉 for each rotation R . We have determined explicit sets of irreducible basis tensors B m l in H l for 1 ≤ l ≤ 8 , which are displayed in tables in this paper. In addition to examples which illustrate the general procedure, we provide, for orthorhombic aggregates of cubic and hexagonal crystallites, explicit expressions of tensorial Fourier expansions of the ODF up to terms with l = 8 , in which the tensorial texture coefficients are given in terms of the classical texture coefficients and the basis tensors B m l . [ABSTRACT FROM AUTHOR]

Depending on the 3D-printing orientation, the anisotropy of the elastic characteristics of the Inconel 625 alloy generated with selective laser sintering from powders is investigated. The impact of the original powder combination and the following heat treatment (post-printing treatment) on the anisotropy of the alloy elastic characteristics is assessed. As demonstrated, the suggested treatments can lessen the anisotropy of the alloy elastic characteristics. Based on knowledge of the elastic constants of the single crystal and x-ray texture features, the results of a theoretical estimation of the elastic and shear moduli, Poisson's ratio, and their anisotropy in the horizontal and vertical directions of 3D printing are provided. As demonstrated, the obtained theoretical values differ by 6-10% from the corresponding experimental values. The calculated stress-strain state can be more accurately calculated with the use of the estimated elastic characteristics and their anisotropy. The strategy for 3D-printing complicated components from Inconel 625 alloy may be made more effective. [ABSTRACT FROM AUTHOR]

Composite materials Bi2Te2.7Se0.3/Teδ with varying concentration (δ = 0.15, 0.2, 0.25, and 0.3) are obtained by the solvothermal synthesis of initial powders and their subsequent spark plasma sintering. During the sintering process, the samples are textured, as a result of which lamellar grains are arranged in layers perpendicular to the direction of the application of pressure during sintering (the direction of the texture axis). Upon magnification, the concentration of superstoichiometric tellurium decreases the degree of texturing. The concentration of tellurium does not affect the average grain size. Superstoichiometric tellurium is distributed along the grain boundaries, as a result of which a structure characteristic of composite materials is formed. The release of tellurium at the grain boundaries leads to a change in the thermoelectric properties of the obtained materials. The electrical resistivity naturally increases, and the total thermal conductivity decreases with an increase in the concentration of superstoichiometric tellurium. [ABSTRACT FROM AUTHOR]

Magnesium and its alloys have tremendous potential as biodegradable implant materials but finding the right compromise between corrosion resistance and mechanical properties is an ongoing investigation. This study utilized equal channel angular pressing (ECAP) to fabricate Magnesium-ZX 30 alloy with a refined uniform microstructure. ECAP processing via routes Bc and A for up to four passes resulted in the evolution of dynamically recrystallized textured α-Mg ultrafine grains with a high fraction of low-angle boundaries. 4Bc and 4A processing via ECAP yielded significant grain refinements of 91.6% and 86.5%, respectively compared to the as-annealed condition. X-ray diffraction verified that the α-Mg phase dominated the microstructure as a result of ECAP processing promoting the dissolution of second phases due to the high density of dislocations and vacancies it generated. Electrochemical analysis revealed that ECAP reduced galvanic corrosion and pitting corrosion. Compared to the as-annealed sample, all ECAP-processed conditions displayed a significant decrease in corrosion rates, most notably among them is the 4A condition (97%). Moreover, the surge in grain boundary density and in grain boundary misorientations accelerated the formation of the passivation film, which enhanced the corrosion resistance compared to the as-annealed conditions by 254%, 418% for the 4Bc and 4A processed conditions, respectively. This was corroborated by an immersion test conducted in ringer lactate solution for 360 h. This current work signifies that ECAP processing is capable of producing ZX30 alloy medical implants with high mechanical properties and excellent corrosion resistance that make it suitable for future in-vitro research. [ABSTRACT FROM AUTHOR]

Al-Li alloy is widely used in aircraft manufacturing due to its high specific strength. The micro-strengthening mechanisms have been investigated widely, including precipitate and solute strengthening. However, the influence of crystallographic texture on mechanical properties remains unclear, because current researches are based on rolled sheet. In this paper, 2198 Al-Li alloy bars were processed using hot extrusion to obtain a texture different from rolling. The mechanical properties were tested via uniaxial tension. The microstructure was observed using scanning electron microscopy, electron backscattered diffraction, and transmission electron microscopy. The results show that the yielding strength and ultimate tensile strength (UTS) of extruded 2198 Al-Li alloy bars are greatly improved due to the precipitation of T1 precipitate after artificial aging. With the increasing of pre-deformation, the number of T1 increases, and the size of T1 precipitate is close to each other, leading to a remarkable increase in strength. When the pre-deformation is 6%, the UTS reaches 611 MPa. 2198 Al-Li alloy bars possess two types of fiber textures: <100> // extrusion direction and <111> // extrusion direction. The presence of <111> fibrous texture with a low Schmid factor can increase the strength of extruded 2198 Al-Li alloy bars. The fracture mechanism of the bar is ductile fracture after artificial aging, while the fracture mechanism is a mix of micropore aggregation and cleavage after natural aging. [ABSTRACT FROM AUTHOR]

This study presents a novel cost-effective Fe30Ni25Cr25Mo10Al10 high-entropy alloy with a dual-phase microstructure that was processed using cyclic closed-die forging (CCDF) at room temperature for a maximum of six passes. The as-homogenized alloy exhibited [CrMoFe]-rich dendrites with dual-size morphology dispersed in an almost uniform face-centered cubic (FCC) matrix. It was found that as the number of CCDF passes increased, leading to a more homogenous nanograin, there was an accumulation of dislocations, fragmentation of [CrMoFe]-rich dendrites, and enhanced distribution within the matrix. These conditions were conducive to the creation of a nanostructured Fe30Ni25Cr25Mo10Al10 alloy with superior mechanical properties. Texture analysis indicated that the prominent texture components for the Fe30Ni25Cr25Mo10Al10 alloy after six passes were Rotated Cube {001}, S {123}, and Dillamore {4 4 11}. After the sixth CCDF pass, the Fe30Ni25Cr25Mo10Al10 alloy exhibited the highest microhardness (∼ 974 HV) and the lowest wear rate (∼ (0.8 ± 0.1) × 10–5 mm3.N−1.m−1). Additionally, it was proposed that the development of the Rotated Cube {001} texture component contributed positively to enhancing wear resistance in the cost-effective high-entropy alloys. Considering the obtained results, it is reasonable to propose that CCDF processing is significant potential for the advancement of cost-effective nanostructured high-entropy alloys for industrial applications.

By elucidating the progressive relationship from the rolling stress state to the activation of slip systems and then to lattice rotation, this paper clarifies the influence mechanism of strain paths on the evolution of α-phase texture in near-α titanium alloys. The distinct rolling textures obtained further provide a robust foundation for investigating whether the competition between different α-phase textures changes with varying cooling rates during β→α phase transformation. In this study, initial Ti65 alloy sheets underwent rolling using three different strain paths (UDR/CDR/MSCR), resulting in the production of three foils characterized by distinct textures. Compressive stress during rolling promotes the activation of basal and pyramidal-II slipping, leading to the formation of a TD-split basal texture in α-phase. Tensile stress during rolling promotes the activation of prismatic slipping, ultimately resulting in a [10 1‾ 0]//RD (in the case of UDR) or [21‾1‾ 0]//RD (in the case of CDR) texture. Variations in stress states along different strain paths led to differences in the global Schmid factor distribution of α-phase for slip systems, ultimately resulting in diverse texture evolution. Subsequently, foil samples underwent two-phase region heat treatments, followed by furnace cooling and air cooling. After furnace cooling, the strength of the transverse texture increased in each type of foils. Conversely, after air cooling, no specific α-phase texture consistently exhibited an increasing trend in the three foils.

The influence of anisotropy induced by the crystallographic texture on the elastocaloric cooling effect of rolled NiTi alloy was investigated. Cyclic tensile tests were conducted along various directions angles (θ) between the rolling direction (RD) and the transverse direction (TD). The results demonstrated that the dominant texture component of the material were {110} and {001}. With the presence of texture component {110} and {001}, the elastocaloric cooling effect of rolled NiTi alloy presented unusual anisotropy. The adiabatic temperature change ΔTadi is maximum in the θ = 0° direction (//RD) and minimum in the θ = 90° (//TD)direction. The material coefficient of performance COPmat and Carnot COP were also analyzed and evaluated. The maximum COPmat and Carnot COP obtained were 26.5 and 67%, respectively, indicating a remarkable balance between cooling capacity and efficiency. The present research shed light on optimizing the elastocaloric cooling effect by introducing crystallographic texture characteristic in rolled NiTi alloy.

Austenitic stainless steels are widely used in industry, from heavy industry and power generation to precision mechanics and electronics, accounting for about 2/3 of the stainless steels produced. The stability of austenite influences the properties and behaviour of these steels during deformation and annealing. This paper presents the results of research into austenitic metastable phase X5CrNi1810 steel, which was subjected to cold rolling (in the range of 5 to 80%) and then annealing (at temperatures of 500-900°C). The research focused mainly on changes in crystallographic texture parameters occurring during the analysed processes. It was found that the observed development of the deformation texture is complex due to the fact that several processes take place simultaneously. Namely, the deformation of austenite, the transformation of austenite into martensite, and the deformation of the resulting martensite. The texture of the deformed austenite was similar to the texture of the alloy type {112} . After 80% deformation, the Goss-type {110} texture component showed the highest intensity. The lack of {112} orientation in the texture was due to the fact that this orientation changes to the {112} martensite orientation as a result of the γ→α’ phase transition. Annealing of the deformed steel at 500°C led to an increase in the degree of texturing (sharpening of the texture), which was related to the improvement of the texture in this temperature range. Above 600°C, the degree of texturing decreased, which is directly related to the α’→γ reverse transformation and the subsequent recrystallization process. Magnetic studies indicate an increasing proportion of the magnetic phase α’ (martensite) together with an increasing degree of deformation. For deformation of 80%, the amount of magnetic phase reached a value of more than 33%. However, after annealing at a temperature of 800°C, there is no martensite in the structure, which indicates that, in these heat treatment conditions, the complete reverse transformation of martensite into austenite has already taken place.

Laser powder bed fusion of metals (PBF-LB/M) is a pivotal additive manufacturing technique that enables the production of intricate components. In addition to enabling the production of complex shapes, it allows for a high degree of freedom in manipulating the microstructure. The present investigation explores the manipulation of the crystallographic texture in AISI 304L stainless steels via PBF-LB/M, due to the possibility of tailoring the secondary hardening phenomena. Neutron diffraction provides efficient texture assessment, while decision tree regression reveals the complex interplay between processing parameters and the resulting crystallographic textures. Our investigation identifies the optimal PBF-LB/M processing parameters for obtaining strong texture along the build and laser scan directions. Additionally, microstructural characterisation of selected samples reveals the complex solidification structures. By employing advanced characterisation techniques and machine learning, this work provides insights into achieving or avoiding specific crystallographic textures during PBF-LB/M processing of stainless steels or other materials.

The microstructural evolution and crystallographic texture formation of β-solidifying Ti-44Al-6Nb-1.2Cr alloy were identified under single- and multi-track exposures via laser powder bed fusion (L-PBF) for various process parameters. Under single-track exposure, the microstructure of the melt pool was divided into the band-like α2 phase in the melt pool boundary and β phase in the melt pool center. Numerical and thermodynamic simulations revealed that the underlying mechanism of phase separation was related to the variation in the cooling rate in the melt pool, whereas microsegregation induced a shift in the solidification path. Meanwhile, the crystallographic texture of the α2 phase region was identical to that of the substrate owing to the epitaxial growth of the β phase and subsequent α phase nucleation. In contrast, the β phase exhibited a ± 45° inclined <100> alignment in the melt pool, which was tilted to align along the build direction toward the center of the melt pool corresponding to the simulated thermal gradient direction. Furthermore, the narrow hatch space condition maintained the crystallographic texture to the subsequent scan, forming a continuous band-like α2 phase with a strong selection. However, the crystallographic texture in a wide hatch space condition manifested a random distribution and constituted a fine mixture of the β and α2 phases. For the first time, these results will offer an understanding of an anisotropic microstructure control via the L-PBF process and ensure the tailoring of the mechanical properties in the β-solidifying γ-TiAl-based alloys by approaching hatch spacing control. [ABSTRACT FROM AUTHOR]

Texturing metallic zinc anodes (MZAs) for selective exposure of (002)Zn plane with high thermodynamical stability is an efficient scheme for dendrite‐free Zn electrodeposition. However, fundamental factors that influence Zn deposition morphology via surface crystallographic texture engineering are not well understood. Herein, different from traditional cognition, MZAs with preferential exposure of (101)Zn facet are demonstrated to be equally effective in promoting dendrite‐free Zn deposition, which is enabled by introducing trace amount (0.01 m) of theophylline into ZnSO4 electrolyte. Experimental results and mathematical model corroborate, indicating mechanistically that the theophylline derived cations preferentially adsorb on the (002)Zn crystal plane due to higher adsorption energy, thereby accelerating its growth through increased binding affinity with Zn2+ ions. Consequently, this phenomenon facilitates the texture exposure of (101)Zn facet to achieve ordered surface crystallographic orientation of MZAs (101‐Zn), thus enabling electrodeposition/dissolution cycling over 650 h under a depth of discharge up to 40% and significantly boosting the rechargeability (76.7% capacity retention after 1000 cycles) of the 101‐Zn||carbon‐cloth@MnO2 full battery relative to counterpart without theophylline additive (36.3%). The work offers deep insights on the scientific links between the surface crystallographic orientation of MZAs and Zn deposition morphology, while opens up vast untapped opportunities to realize dendrite‐free MZAs. [ABSTRACT FROM AUTHOR]

Selective laser melting (SLM) of heat-resistant nickel alloy VZh159 is used to show that at constant energy density the key factor determining the texture and the internal stresses is the hatching distance. At multiple increase in the exposure rate and decrease in the hatching distance, the micropore proportion increases exponentially due to enhancement of the dissipation of the laser radiation caused by reflection in the track overlapping zone. [ABSTRACT FROM AUTHOR]

Analysis of published data on the effect of the exposure algorithms, energy, and scanning speed on the geometric characteristics of the molten pool and its fine structure, on the texture and grain structure of metallic materials synthesized by selective laser melting (SLM) is presented. A regression model describing the correlation between the required laser energy density and the powder composition characteristic temperatures during SLM of heat-resistant nickel- and cobalt-based alloys is obtained. [ABSTRACT FROM AUTHOR]

Austenitic stainless steels are widely used in industry, from heavy industry and power generation to precision mechanics and electronics, accounting for about 2/3 of the stainless steels produced. The stability of austenite influences the properties and behaviour of these steels during deformation and annealing. This paper presents the results of research into austenitic metastable phase X5CrNi1810 steel, which was subjected to cold rolling (in the range of 5 to 80%) and then annealing (at temperatures of 500-900 °C). The research focused mainly on changes in crystallographic texture parameters occurring during the analysed processes. It was found that the observed development of the deformation texture is complex due to the fact that several processes take place simultaneously. Namely, the deformation of austenite, the transformation of austenite into martensite, and the deformation of the resulting martensite. The texture of the deformed austenite was similar to the texture of the alloy type {112}<110>. After 80% deformation, the Goss-type {110}<001> texture component showed the highest intensity. The lack of {112}<111> orientation in the texture was due to the fact that this orientation changes to the {112}<110> martensite orientation as a result of the γ → α' phase transition. Annealing of the deformed steel at 500 °C led to an increase in the degree of texturing (sharpening of the texture), which was related to the improvement of the texture in this temperature range. Above 600 °C, the degree of texturing decreased, which is directly related to the α' → γ reverse transformation and the subsequent recrystallization process. Magnetic studies indicate an increasing proportion of the magnetic phase α' (martensite) together with an increasing degree of deformation. For deformation of 80%, the amount of magnetic phase reached a value of more than 33%. After annealing at a temperature of 800 °C, there is no martensite in the structure, which indicates that, in these heat treatment conditions, the complete reverse transformation of martensite into austenite has already taken place. [ABSTRACT FROM AUTHOR]

Ferroelectric (FE) hafnium zirconium oxide (HZO) is an excellent candidate for data storage applications. However, it has some reliability limitations such as imprint and retention. Herein, we explore Al doping of HZO to overcome these limitations. FE behavior is tuned by the aluminum (Al) concentrations in the films and by annealing temperature. A correlation is done between electrical behavior, crystallographic texture, and FE phases determined by grazing-incidence X-ray diffraction (GIXRD) measurements. Reduced coercive field (2Ec) values and wake-up free HZO-based ferroelectrics are explored. We show the tunability of remanent polarization (2Pr) and 2Ec with respect to Al-doping concentration and anneal temperature, hence crystallographic texture.

The thermo-stability of microstructure during isothermal annealing at 900 °C and 1000 °C in a cold-worked Cu-Al2O3 composite with 0.1 wt.% Al content and its effect on resistance to softening were investigated in this paper. The results reveal that the microstructure following cold deformation consists of a Cu matrix with a refined grain size and high-density dislocations, accompanied by dispersed Al2O3 nanoparticles exhibiting an extremely low volume fraction. During isothermal annealing at 900 °C, the Al2O3 nanoparticles can strongly restrict the migration of the dislocations and suppress the recrystallization of the fine-grained Cu matrix by the Zener pinning effect. Furthermore, the presence of pinned dislocations facilitates the formation of sub-grain boundaries comprising high-density dislocations. Consequently, the Cu-Al2O3 composite with 0.1 wt.% Al content exhibits remarkable thermo-stability in its microstructure due to the incorporation of Al2O3 nanoparticles, resulting in a significantly elevated softening temperature of up to 1000 °C and thereby demonstrating excellent resistance against softening. However, the observed phenomenon of softening after isothermal annealing at 1000 °C for 5 hours can be attributed to extensive recrystallization growth that promotes twin boundary formation, primarily caused by the weakening Zener pinning effect resulting from Oswald ripening of Al2O3 and rod-like Al2O3 formation.

This study evaluated the effect of dedicated heat treatments (1050°C, 1100°C, 1142°C, and 1185°C/2 h + double-aging) on the uniaxial tensile properties at elevated temperature (650°C) of Inconel® 718 fabricated via arc plasma directed energy deposition. They enabled to meet, for the first time, the AMS 5662 requirements at elevated temperature. Tensile tests exhibited ductile strain–stress curves. The 1100°C/2 h + double-aging showed the best performance (YS0.2%, UTS, and elongation of 967 MPa, 1126 MPa, and 18.7%, respectively). Additionally, vertical specimens evidenced dynamic strain aging, although no brittle-like features were observed.

The application of equal-channel angular pressing (ECAP) to TA4 pure titanium (Ti) results in a fine-grained microstructure. This technique presents an substitute for alloying, delivering enhanced mechanical properties without reducing biocompatibility and corrosion resistance. This study employs scanning electron microscopy (SEM), X-ray diffractometry (XRD), and transmission electron microscopy (TEM) to explore the microstructure evolution and the toughening mechanism of TA4 pure Ti after deformation. ECAP performed at 573 K endows TA4 pure Ti with a uniformly fine-grained microstructure, leading to a significant enhancement in its mechanical properties, exemplified by a yield strength of ∼731.9 ± 2.7 MPa and an elongation of ∼30.8± 1.3 %. While the {0001} basal slip primarily governs the ECAP deformation, the non-basal slip plays an increasingly important role with the increase of passes. The increase of yield strength can be attributed to grain refinement and the modification of the {0001} basal texture. Meanwhile, the improvement of plasticity is related to the strengthening of the {101‾ 0} prismatic texture. These findings offer fresh insights and methodologies for the design and manufacture of high-performance biomedical pure Ti.

The current research provides an insight into the correlation between the crystallographic textures, microstructure, and hardness of friction stir welded joints in nanostructured AA2024 alloys processed through accumulative roll bonding (ARB). Utilizing varying rotational speeds (250, 500, 750, and 1000 rpm) at a constant traverse tool (150 mm/min) during friction stir welding (FSW), microstructural analyses reveal distinct grain structures and texture components in the nugget zone. The fully recrystallized Cube {001}⟨100⟩ texture-oriented grains appear at the rotational speed of 750 rpm. The hardness profiles of ARB-processed strips after FSW at different rotational speeds show local softening in the nugget zones. There might be a hypothesis concerning the dissolution of stable and metastable precipitates based on generated heat input, providing insights into the mechanisms influencing hardness variations. Notably, the examination of Cube {001}⟨100⟩ texture and its correlation with local softening adds a valuable dimension to the understanding of microstructural changes in FSW of nanostructured AA2024 alloys processed by accumulative roll bonding process.

In this research, the efficacy of specific heat treatment procedures in mitigating hydrogen embrittlement in X100 pipeline steels is discussed. The studied steels underwent a one-step austenitization process at temperatures of 780 °C (HT1), 830 °(HT2), and 880 °C (HT3) for 90 min, followed by oil quenching, tempering at 600 °C, and air cooling. The susceptibility of both the heat-treated and as-received (REF) specimens to HIC was assessed using an electrochemical hydrogen charging, tensile testing, micro-hardness testing, and electron backscatter diffraction (EBSD) techniques. The results showed that an increase in annealing temperature from 780 to 880 °C considerably decreases hydrogen embrittlement susceptibility. The hardness value at the centerline of the as-received (REF) specimen was found to be higher than that of the heat-treated specimens. Additionally, calculations of the hydrogen embrittlement (HE) index for all specimens were conducted. The results show that the REF specimen, which demonstrated the highest hardness and HE index values, has greater susceptibility to HIC. Conversely, the HT3 specimen, which was annealed at 880 °C and displayed the lowest hardness and HE index values, showed commendable resistance to HIC. The EBSD analysis revealed a decrease in Kernel average misorientation (KAM) values in heat-treated specimens, with the lowest values found in HT3. Dominant textures in all studied steels, {011} and {111}, were considered HIC-resistant and recrystallization mapping indicated a peak area of recrystallized grains in the REF specimen. [ABSTRACT FROM AUTHOR]

The effect of weld chemistry (two types of electrodes (E2594 and E2595)) on the microstructure and texture development using electron back scattered diffraction and thermal stability during shielded metal arc welding of alloy 2507 have been studied. Base metal showed alternate bands of austenite (γ) and ferrite (δ) in almost equal fractions. Weldments were mainly comprised of 3 zones, namely base metal zone (BMZ), heat affected zone (HAZ), and weld metal zone (WMZ). After welding, ferritic solidification mode was found with diverse morphologies of austenite viz. grain boundary austenite, Widmanstatten austenite, and intergranular austenite and a decrease in the fraction of austenite in WMZ and HAZ. The texture intensity of δ was observed to be higher than that of γ. This implies a stronger texture for δ (a strong rotated cube texture 001 110 along with minor α-fibre rolling direction , RD / / 110 and γ-fibre normal direction , ND / / 111 ) than γ [Brass, Cu, Goss and S texture components ( 110 112 , 112 111 , 110 001 and 123 634 , respectively)] in the annealed state (BMZ). γ/δ grains showed the Kurdjumov–Sachs (K–S) orientation relationship. Kernel average misorientation (KAM) graphs/maps showed no significant change in BMZ but a substantial decrease in KAM values in δ than γ for both weldments. The peak temperature attained was sufficiently higher than the melting temperature of base/filler metal suggesting the proper melting and diffusion of molten metal throughout the thickness. The size of the melt pool widened for E2594 and was relatively small for E2595. [ABSTRACT FROM AUTHOR]

This study examined mechanical properties of AA2024 alloy and its correlation between strain path and crystallographic texture. Accumulative roll bonding (ARB) and cross accumulative roll bonding (CARB) were used to severely deform AA2024 alloys. Electron backscatter diffraction (EBSD) studies demonstrated that nano/ultrafine grains were formed by the strain routes after eight cycles. It was also found that the lamellar boundary spacing and the mean boundary spacing were ~ 360 ± 10 nm and 845 ± 10 nm after eight ARB cycles. In contrast to the ARB, the CARB specimen had equiaxed microstructures characterized by grains with a size of 150 and 100 nm. The CARB processed specimen exhibited a mean misorientation angle of 41.83° and a fraction of high angle grain boundaries of 78%, these values were 34.57° and 67% for ARB treated specimen, respectively. It was observed that the evolved texture is greatly affected by the strain paths. The ARB processed specimen revealed strong Copper {112} <111>, Dillamor {4 4 11} <11 11 8>, S {123} <634>, and Brass {011} <211> components. In contrast, the CARB processed specimen showed major texture with prominent Copper {112} <111>, Brass {011} <211>, Rotated Cube {001} <110>, S {123} <634>, and Goss {011} <100> components. In the CARB specimen, the Goss/Brass texture ratio was intensified and the mechanical properties were superior (tensile strength: 535 MPa, microhardness: 182 HV, elongation: 11.9%) compared with the ARB processed specimen (tensile strength: 455 MPa, microhardness: 145 HV, elongation: 9.2%). Further, the change in strain path did not significantly affect the intensity of Goss and Cube components, ruling out any further recrystallization tendency. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of dedicated heat treatments (1050°C, 1100°C, 1142°C, and 1185°C/2 h + double-aging) on the uniaxial tensile properties at elevated temperature (650°C) of Inconel® 718 fabricated via arc plasma directed energy deposition. They enabled to meet, for the first time, the AMS 5662 requirements at elevated temperature. Tensile tests exhibited ductile strain–stress curves. The 1100°C/2 h + double-aging showed the best performance (YS0.2%, UTS, and elongation of 967 MPa, 1126 MPa, and 18.7%, respectively). Additionally, vertical specimens evidenced dynamic strain aging, although no brittle-like features were observed. Dedicated heat treatments developed for Inconel® 718 fabricated via arc plasma directed energy deposition enabled compliance with AMS 5662 requirements at elevated temperature (650°C). [ABSTRACT FROM AUTHOR]

The structure, texture, and mechanical properties of a C27400 brass (63% Cu–37% Zn) after alternating elastic–plastic deformation were studied. A 3-mm thick brass strip after softening annealing was subjected to alternating bending through one pass (19 bending acts) using an ARKU 25/21 precision roller straightener. Electron microscopy, x-ray texture analysis, microhardness measurements, and tensile testing were used to characterize the material. It has been established that the alternating bending leads to an increase in the yield point of a thick strip by 62% and the ultimate tensile strength by 12%, while the relative elongation is slightly reduced from 57 to 52%. Such a set of properties is provided by the grain structure refinement through the twinning mechanism; after alternating bending, the average grain size decreases more than 2 times. The contribution of different layers of the strip to the overall hardening is estimated. The anisotropy of the mechanical properties and its relation to texture was studied. [ABSTRACT FROM AUTHOR]

It is well known that the properties of polycrystalline metals are related to grain boundaries (GBs), which are fundamental structural elements where crystallographic orientations change abruptly and often exhibit some degree of symmetry. Grain boundaries often exhibit unique structural, chemical, and electronic properties that differ from bulk crystalline domains. Their effects on material properties, including mechanical strength, corrosion resistance, and electrical conductivity, make grain boundaries a focus of intense scientific investigation. In this study, the microstructural transformation of an AlSi10Mg alloy subjected to KoBo extrusion and subsequent annealing is investigated. A notable discovery is the effectiveness of a strain-annealing method for grain boundary engineering (GBE) of the LPBF AlSi10Mg alloy. In particular, this study shows a significant increase in the population of coincidence site lattice boundaries (CSL), which embody the symmetry of the crystal lattice structure. These boundaries, which are characterised by a high degree of symmetry, contribute to their special properties compared to random grain boundaries. The experimental results emphasise the crucial role of strain-induced boundary migration (SIBM) in the development of a brass texture in the microstructure of the alloy after annealing. In addition, the presented results demonstrate the feasibility of applying GBE to materials with high stacking fault energy (SFE), which opens up new possibilities for optimizing their properties. [ABSTRACT FROM AUTHOR]

Recently, Man and Du, in the context of classical texture analysis where the orientation distribution function (ODF) is defined on the rotation group SO(3), presented a systematic procedure by which the classical expansion of an ODF truncated at the order l=L can be directly rewritten as a tensorial Fourier expansion truncated at the same order. In classical texture analysis, the groups of crystallite and texture symmetries are assumed to be subgroups of SO(3), which is unreasonable, say, for aggregates of crystallites in a crystal class defined by an improper point group. In this paper, we consider ODFs defined on the orthogonal group O(3) and extend the aforementioned procedure to write down tensorial Fourier expansions for polycrystals with crystallite symmetry defined by any of the 21 improper point groups. Examples that illustrate the general procedure are given. This article is part of the theme issue 'Foundational issues, analysis and geometry in continuum mechanics'. [ABSTRACT FROM AUTHOR]

Advantages of the laser powder bed fusion (LPBF) process over conventional processing methods include microstructural control capability and complex geometry parts fabrication. For most alloys, the microstructure–property relationship typically guides the LPBF process toward achieving application‐specific properties. Nonetheless, the LPBF process produces a high degree of anisotropy, primarily from the epitaxial preferred grain growth mechanisms during solidification and the consequent highly textured microstructures produced. The crystallographic texture‐controlled build concept through the LPBF process is a material design and processing approach gaining a lot of interest because of the promising unique and superior properties offered by the anisotropy accompanying the LPBF process. The numerous attempts at intentional texture‐controlled building or parts fabrication from structural materials using the LPBF process warrant an up‐to‐date review. Thus, this review presents solidification mechanisms that influence texture evolution during the LPBF process such as the melting mode, melt pool shape, influence of thermal gradient, and solidification rate. Furthermore, this review delves into the influence of LPBF process parameters on texture, accompanying microstructural evolution, and the intentional control of texture effects on properties such as mechanical, corrosion, and oxidation resistance. [ABSTRACT FROM AUTHOR]