Melt electrowriting (MEW) is a less-explored yet promising additive manufacturing technique for fabricating tissue-engineered scaffolds with the designed microarchitecture. One of the significant advantages of MEW is the ability to manufacture scaffolds with controlled thinner fiber strands, which cannot be produced by other competitive techniques, like electrospinning. The key requirements for melt electrowritability include melt viscosity, electroactivity of the biomaterial ink, among other factors. Although poly (ε-caprolactone) (PCL) scaffolds have been widely investigated in the MEW domain, their inherently low electroactivity remains a major limitation. To address these challenges, we systematically investigated the melt electrowritability of biomaterial inks comprising of PCL and barium titanate (10-30wt% BT), with a particular focus on component miscibility, rheological behavior, printability, mechanical strength /modulus and cytocompatibility. The MEW process parameters for PCL/10BT were systematically optimized to achieve consistent fiber deposition (∼30μm diameter) and high-fidelity deposition. In contrast, PCL/20BT and PCL/30BT scaffolds exhibited poor and irreproducible printability. The interplay between MEW process parameters (printing pressure, collector distance, printing speed melt temperature) and printability has been critically analyzed in terms of BaTiO3 loading-dependent melt viscosity, shear alignments of fibers, flow stability, and fiber trajectory/structure continuity. While 10% BaTiO3 addition to PCL biomaterial ink substantially enhances 3D printability and buildability (10 layers) in MEW route, the orientational dependence of tensile properties (strength/modulus) is attributed to multilayered structure, with anisotropic behavior being analogous to fiber-reinforced composites. Additionally, the buildability limitation, beyond 40 layers of PCL/10BT to produce a fibrous scaffold construct has been attributed to the polarization-induced residual surface charge accumulation and spatial distribution, promoting interlayer repulsion. Cytocompatibility study using NIH3T3 fibroblasts revealed excellent cellular alignment and growth on melt electrowritten fiber strands of PCL/10BT, in a manner much better than pristine PCL. Overall, this study demonstrates the beneficial effect of BaTiO3 incorporation on the mechanical and biological performance of MEW-processed PCL scaffolds, while highlighting printability limitations at higher BaTiO3 contents.

Understanding conical penetration into layered biological materials requires capturing the coupled influences of anisotropy, curvature, layer architecture, and developmental evolution of material properties. However, existing computational studies typically assume adult bone, neglect multilayer skull structure, or simplify cortical anisotropy. Here, we develop a multilayer finite element framework that integrates age-dependent cortical thickness, diploë formation, anisotropic elastic behavior, and Hill-type anisotropic yield to resolve penetration mechanics across developmental stages. A data-driven strategy is used to estimate geometry and material properties by fitting a monomolecular growth model to experimental measurements of thickness, modulus, and strength spanning infancy through adulthood, producing a continuous and physiologically realistic map of skull property evolution. The model is validated against independent wedge-indentation experiments and reference finite element simulations, demonstrating close agreement in force-displacement behavior and subsurface stress distributions. Results reveal that age-driven changes in cortical thickness and stiffness produce more than a three-fold variation in penetration depth and a four-fold variation in penetration depth as a percentage of the outer cortical layer thickness, under identical loading. Marked differences in shear-stress localization and plastic-zone morphology highlight how layer geometry and anisotropic stiffness collectively govern penetration resistance. These findings provide new mechanistic insight into the indentation response and pin slippage of layered cranial bone and underscore the importance of age-specific material modeling. The framework has direct implications for biomechanical safety when using head-immobilization devices, particularly in pediatric neurosurgery, where predictive modeling of tool-bone interaction can inform improved device design, force recommendations, and clinical practice.

Anisotropic mechanical behavior and failure pathways of bilayer borophene: A deep learning molecular dynamics study

Digital Light Processing (DLP) offers high resolution and expedited production in additive manufacturing; nevertheless, the fragility and dimensional inaccuracy of photopolymer resins persist in posing significant constraints. This study investigates the impact of incorporating chitosan (0–10 wt%) into a blended photopolymer system composed of standard resin (epoxy-diacrylate based) and flexible resin (methacrylate-based). Mechanical characterization was conducted using tensile, flexural, impact and hardness testing, supplemented by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and assessment of dimensional shrinkage. The results of this study demonstrated uniform enhancements in tensile strength, flexural strength, and hardness as the content of chitosan increased. In contrast, impact energy specific exhibited a decline at low concentrations (2–4 wt%), followed by a recovery phase at 6–8 wt%, and a substantial surge at 10 wt%, reaching approximately two times the value of the pure blended resin. The SEM and FTIR investigations validated the interfacial interactions and dispersion processes aligned with these mechanical patterns. Dimensional assessment revealed contraction along the X and Y axes; however, an unforeseen expansion transpired in the Z-axis, which was attributed to overcuring. The findings indicate that the chitosan enhances mechanical characteristics and causes anisotropic dimensional responses in DLP printing. These insights offer essential direction for enhancing filler content and processing conditions to produce more robust and dependable photopolymer composites for additive manufacturing applications.

Plantar skin is a highly specialised tissue which protects the foot from injuries and adapts to external stresses. However, it can be subjected to diabetic plantar ulcers, which are among the most difficult and costly wounds to treat. Although this is a crucial topic, few studies have focused on the mechanical properties of foot skin and how disease alters them. In this context, this work aims to fully describe the mechanical behavior of plantar skin through experiments and constitutive analysis. Different experimental tests (failure tensile tests, unconfined compression at different strain rates, stress relaxation tests) were conducted on human plantar skin samples cut along the posterior-anterior (PA), lateral-medial (LM), and cranial-caudal (CC) directions. Then, experimental results were used to identify, through an inverse analysis, the parameters of the anisotropic visco-hyperelastic constitutive model adopted to describe the skin's mechanical response. Plantar skin's non-linear, anisotropic, and time-dependent behavior, with differences between the anterior and posterior foot's regions. In addition, the constitutive model adopted is able to capture the mechanical behavior of the plantar skin Failure tensile tests showed that PA directions exhibited higher elastic modulus than LM directions in both posterior (22.05 vs 12.91MPa) and anterior (17.39 vs 12.82MPa) regions, while the unconfined compression tests revealed that compressive elastic moduli in the posterior region increased with increasing strain rates. The proposed model provides new insights into the mechanics of plantar skin, being a valuable tool for applications such as diagnosing skin diseases and developing skin substitutes.

ABSTRACT CMT+Pulse arc additive manufacturing encounters challenges, including poor dimensional accuracy, high defect susceptibility, and insufficient mechanical performance. To overcome these limitations, this study develops a novel automated CMT+P arc reciprocating additive manufacturing strategy with dynamic flexible control and short dwells at arc start/stop points to maintain low heat input. This method effectively suppresses weld bead protrusions and concave defects. Results show that the S2-step method improves forming quality, reducing height discrepancies at arc start/stop positions by 21.43% vs. the two-step method. Uniform hardness (max 201HV0.5), EL=61%, YS=324 MPa, UTS=679 MPa, high strength‑ductility synergy, anisotropic mechanical behavior, and ductile fracture are achieved. A large component (1000 mm height, 456 mm outer diameter, 55 mm wall thickness) with a smooth surface is successfully fabricated. This work provides a new approach for regulating microstructure and mechanical properties in robotic arc additive manufacturing, supporting efficient, low‑energy, high‑performance fabrication of large‑scale metal components.

We presents in this study a comprehensive analysis of the structural, mechanical, electronic, and optical properties of X2MgGeY6 (X = Na, K; Y = Cl, I) perovskite compounds via density functional theory (DFT). The analyzed structural parameters are in close agreement with the available data of the computed structures. The tolerance factor and the positive phonon frequencies in the band structures, authenticate the structural and dynamic stabilities. Analysis of electronic spectra shows that all examined compounds exhibit semiconducting characteristics, with indirect bandgap of 3.13, 1.70, 3.16 and 1.72 eV, respectively. Mechanical analysis confirmed the ionic bonding nature of these materials, as evidenced by positive Cauchy pressure values. As well, the mechanical stability criteria and elastic constants further validate their stability, anisotropy, and ductile behavior. Multiple optical parameters are analyzed including dielectric functions, absorption coefficients, optical conductivity, refractive index and related features with the findings suggest the outstanding optoelectronic performance for photodetectors and LEDs, while iodine-based compounds demonstrate superior potential for solar cell applications. Furthermore, all materials exhibited elastic, thermodynamic, and dynamical stability, confirming their feasibility for practical applications.

Single Point Incremental Forming (SPIF) has attracted increasing attention as a flexible manufacturing route for complex sheet metal components; however, its broader industrial adoption remains constrained by limited predictive accuracy in thickness distribution and surface integrity, particularly for non-axisymmetric geometries. In this study, a combined numerical-experimental framework is developed to investigate and validate the SPIF process applied to truncated quadrilateral panels fabricated from AA1050 aluminum alloy. A three-dimensional finite element model incorporating a Voce strain hardening law, calibrated from uniaxial tensile experiments, is employed to accurately capture material anisotropy and plastic deformation behavior. The numerical predictions of wall thickness distribution and thinning evolution are systematically compared with experimental measurements along the inclined walls of the formed components. The results demonstrate a high level of agreement, with an average thickness deviation below 2%, confirming the reliability of the proposed material model and simulation strategy for complex, non-axisymmetric SPIF geometries. Beyond thickness prediction, the study provides a detailed experimental assessment of surface roughness evolution as a function of key process parameters. The effects of tool diameter (6–14[Formula: see text]mm) and vertical downstep (0.5–1.5[Formula: see text]mm) on surface integrity are quantified under controlled forming conditions. The findings reveal that increasing tool diameter effectively reduces surface waviness by enlarging the tool-sheet contact area, while decreasing the downstep significantly enhances surface smoothness by promoting closer conformity between successive tool paths. Comparative analysis indicates that downstep exerts a more dominant influence on surface quality than tool diameter. The originality of this work lies in the integrated validation of thickness uniformity and surface integrity for truncated quadrilateral SPIF components using a calibrated Voce-based constitutive framework, combined with a systematic evaluation of surface roughness control mechanisms. The results provide practical guidelines for parameter optimization and offer clear implications for high-precision manufacturing applications, including aerospace panels, biomedical components, and customized engineering structures.

Thermoelectric generators (TEGs) are vital, reliable energy sources for both extreme environments such as deep space exploration and off-grid terrestrial applications, as well as emerging fields like wearable energy harvesters and biocompatible medical sensors. This study focuses on tin selenide (SnSe) combined with ductile silver sulfide (Ag 2 S) to leverage their complementary properties: SnSe’s promising thermoelectric performance and mechanical robustness for homojunction TEGs, and Ag 2 S’s exceptional ductility and thermal sensitivity ideal for flexible, biocompatible devices. Materials were synthesized using scalable powder metallurgy and spark plasma sintering (SPS) techniques, ensuring reproducibility and microstructural control tailored for these diverse applications. Our Bi-doped polycrystalline SnSe exhibits a unique polarity switching phenomenon and anisotropic behavior influenced by dopants (Bi, Ag, In), enabling optimized thermoelectric and mechanical properties that reduce interfacial stresses and enhance durability in harsh conditions. Meanwhile, the Ag 2 S materials combine thermoelectric efficiency with fast thermal response and flexibility, suited for continuous physiological monitoring in wearable systems. The hybrid integration of SnSe homojunctions with flexible Ag 2 S devices opens new possibilities for durable, efficient thermoelectric energy harvesting across wide temperature gradients in aerospace and biomedical fields.

Optical anisotropy and phase-matching capability are critical requirements for high-performance nonlinear optical (NLO) crystals, yet they are inherently difficult to achieve simultaneously. Chiral metal-organic frameworks (CMOFs), with tunable coordination environments and crystal symmetry, provide a promising platform for addressing this challenge. Herein, a coordination geometry-directed strategy is proposed to regulate optical anisotropy and phase-matched nonlinear optical behavior in CMOFs. By employing the same chiral ligand while varying the metal centers (Zn2+ versus Cd2+), two CMOFs featuring tetrahedral and octahedral coordination geometries were constructed, leading to distinct crystal symmetries and lattice anisotropies. Structural analysis reveals that the octahedrally coordinated Cd-based framework exhibits symmetry lowering and pronounced unit-cell anisotropy, resulting in a markedly enhanced birefringence (Δn = 0.113 experimentally and 0.198 theoretically at 546 nm), nearly three times that of its Zn analogue. As a consequence, effective phase-matchable second-harmonic generation is achieved, with an SHG efficiency comparable to that of KDP. Density functional theory calculations further demonstrate that the distorted octahedral coordination geometry and coordination-enhanced charge redistribution give rise to strong electronic anisotropy, polarizability anisotropy, and hyperpolarizability. This work establishes coordination geometry as a decisive structural parameter for directing optical anisotropy and nonlinear optical performance in CMOFs.

Anisotropic behavior and mechanism in electropulsing-assisted deep drawing of Ti/al laminated composite cups

Mesoscopic mechanisms of anisotropic suffusion behaviors of gap-graded soil: Identifying preferential suffusion paths based on strong-force chains and anisotropic pore structures

We present a versatile system capable of performing angular-dependent magnetic-field measurements under low-temperature and high-pressure conditions. In our design, the rotation module is mounted at the top of the sample chamber, where the rotating-seal technique prevents gas leakage during rotating. This setup allows any measuring probe inserted into the chamber to rotate synchronously within the magnetic field without requiring a specially designed sample holder. The configuration ensures precise angular control and minimizes mechanical errors arising from thermal contraction. Moreover, by configuring the pressure cell in horizontal or vertical modes, both in-plane rotation and in-plane to out-of-plane magnetic field rotation can be achieved. Overall, the system provides a universal and reliable platform for studying anisotropic magnetotransport behaviors of materials under extreme conditions, offering broad applicability to condensed matter physics and spintronic research.

Multiscale study on mechanical anisotropy and interfacial behavior of 3D printed biodegradable polymer composites

ABSTRACT This study provides complete investigation of electronic, elastic, optical, structural mechanical and thermodynamic characteristics of quaternary mixed‐anion oxyfluorides X ScO 2 F ( X = Ba, Sr, Ca, and Ra) compounds by employing GGA and PBE codes in density functional theory (DFT) method. The determined direct band gaps are reported in the energy range of 1.372 to 3.013 eV by GGA‐PBE approach, while the values are 1.970 to 4.054 eV by hybrid HSE06 approach revealing that all compounds are semiconductors. Moreover, the investigation of thermodynamic properties is performed with the help of density functional perturbation theory (DFPT) method and the estimated zero‐point energy of X ScO 2 F ( X = Ba, Sr, Ca, and Ra) compounds are 0.2977, 0.1826, 0.1910, and 0.2377 eV, respectively. The variation in zero‐point energies reveal that atomic interactions and bond strengths are quite sensitive to all these compounds, as the temperature increases, the heat capacity (C V ) reaches to the Dulong–Petit limit is approximately at 600 K. In XRD, each compound has a distinct diffraction peak and the characteristic peak at 30° which is confirming the tetragonal structure with P4/mmm space group. Optical topologies have predicted the high values of absorption (10 5 ), dielectric function (7–11) and refractive index (2.5–3.5) in the visible and near ultraviolet regions, indicating that these compounds have potential for solar energy applications. All compounds have exhibited the anisotropic behavior in the XY, YZ, and XZ planes, while mechanical properties with their mechanical factor (B/G > 1.75) are verifying their ductility and indicating that they are appropriate for next generation flexible photovoltaic solar cell applications.

Dual-phase steels (DP590 and DP780) are widely utilized in automotive applications due to their high strength and good formability. However, their anisotropic behavior necessitates advanced constitutive modeling beyond conventional isotropic assumptions. This study characterizes the anisotropy of DP590 and DP780 sheets through a series of experiments, including uniaxial tensile, plane-strain and shear tests. Constitutive models are developed under assumptions of associated and nonassociated flow rules (NAFRs) to capture the experimental observation. The developed constitutive models were then implemented in a VUMAT subroutine for the ABAQUS/Explicit solver, considering Hill’s quadratic yield function to simulate plane-strain and shear tests for validation. Comparison between the experimental and numerical responses demonstrates advantages of the model developed under the NAFR approach, which provides superior accuracy than that of models developed under the associated flow rule approach. The developed model based on NAFR significantly improves the predictive accuracy of dual-phase steels in forming simulations.

While diverse previously fabricated pristine and hydrogenated borophene lattices have been characterized predominantly by their metallic nature, a recent experimental breakthrough has introduced α'-B8H4, a semiconducting hydrogenated borophene phase, opening new avenues for boron-based nanoelectronics. Spurred by this breakthrough, herein we utilize a comprehensive first-principles framework to investigate the critical properties of α'-B8H4 monolayer. Stability analyses confirm the considerable dynamical and thermal robustness of the α'-B8H4 monolayer. Calculations using hybrid functionals show that suspended single-layer α'-B8H4 exhibits an indirect semiconducting behavior, with band gaps of 2.06 eV and 2.45 eV predicted by HSE06 and PBE0, respectively. Optical response calculations reveal strong in-plane absorbance in the UV region, with the first notable peak at ~3.65 eV and the main peak occurring between 4.20 and 4.45 eV, both of which are clearly within the ultraviolet range. Mechanical analysis reveals that α'-B8H4 exhibits decent in-plane strength (>10 N/m), while phononic transport calculations yield a moderately low room-temperature lattice thermal conductivity of ~20 W/m·K, both displaying slight anisotropic behavior. These results provide a comprehensive first-principles characterization of the α'-B8H4 monolayer, highlighting the rare emergence of semiconducting behavior in borophene derivatives and underscoring its potential for UV optoelectronics and nanoscale device applications.

Carbon Fiber-Reinforced Polymer (CFRP) composites represent a transformative class of structural materials, combining low density, high specific strength, and excellent fatigue resistance. This review provides a comprehensive overview of CFRPs, addressing their structure, manufacturing routes, mechanical performance, and functional behavior, with particular emphasis on damage tolerance, tribological properties, and environmental durability. The discussion begins with the classification and morphology of carbon fibers, highlighting their influence on composite anisotropy and interlaminar behavior. The effects of impact loading, delamination, and environmental conditioning on residual strength and fatigue life are then examined, with reference to established evaluation methods such as ASTM D7136 and compression-after-impact (CAI) testing. From a tribological perspective, the incorporation of nanoscale additives, such as graphite nanoplatelets and TiO2 nanoparticles, and their contribution to enhancing wear resistance by promoting the formation of stable tribofilms, is explored. Advances in processing techniques, including low-pressure curing and improved resin systems, are also discussed for their roles in enhancing manufacturability and energy efficiency. Overall, the review underscores that optimal CFRP performance is achieved through the synergistic integration of fiber architecture, matrix design, and precise processing control, while future progress in nanomodification, recycling, and sustainable curing technologies is expected to further expand CFRP applications in the aerospace, automotive, and high-performance engineering sectors.

This study introduces a new synthesis algorithm for triply periodic minimal surfaces based on determining the equilibrium configuration of elastic membranes constrained at their boundaries. Beyond the methodology itself and its computational efficiency, the scientific relevance of this work lies in the 66 surfaces with these characteristics that it enabled to generate. Leveraging their continuous and highly regular geometry, these surfaces were used to define novel shell-based lattices, the mechanical behavior of which was investigated numerically and experimentally through both static and dynamic analyses. The computational models demonstrated high predictive accuracy, with numerical results deviating by less than 10% from the experimental data. Across the new geometries, the surface-area-to-volume ratio ranged from 1.8 to 4.8cm−1. At infill coefficients of 10%, 20%, and 30%, the structures exhibited a wide range of stiffness and anisotropic behaviors, with equivalent elastic modulus spanning from 0.02% to 25% that of the base material and Zener indices from 4.67×10−2 to 11.8. Ultimately, the study revealed a clear influence of cell geometry on stress concentration and modal response.

While the effects of formulation variables of a rubber compound are well established for conventional rubber manufacturing techniques, their role in extrusion-based additive manufacturing remains underexplored. This study explores the impact of different base rubbers (NBR and EPDM) and curing agents (sulfur and peroxide) on processability and final part characteristics in material extrusion additive manufacturing applications. Under identical printing conditions, sulfur-cured NBR exhibits greater post-print shrinkage (12%) than sulfur-cured EPDM (7%). However, sulfur-cured NBR achieves a higher degree of adhesion between printed layers than sulfur-cured EPDM, as suggested by the % retention of the bulk materials' ultimate stress by the printed parts (84-100% and 51-62%, respectively). Additionally, a peroxide-cured NBR formulation was compared against the same sulfur-cured NBR formulation. Printed parts from the peroxide-cured NBR formulation showed higher shrinkage (16%) and lower % retention of the bulk materials' ultimate stress (26-33%) than the sulfur-cured NBR formulation. Additionally, the tensile behavior of all three rubber compounds was found to be strongly dependent on printing orientation, showing the anisotropic behavior typical of extrusion-based additive manufacturing. Sulfur-cured NBR showed the least anisotropy for stress at break (0.82) and strain at break (0.90), whereas peroxide-cured NBR showed the highest anisotropy in stress (0.74) and strain (0.82). The anisotropy ratios for sulfur-cured NBR and EPDM compounds were very similar for stress (0.82 vs. 0.82) and comparable for strain (0.90 vs. 0.87). Notably, the peroxide cure system provided almost twice as much available printing time as the sulfur cure system. This report on the effects of base rubber and curing agents on 3D printability and part properties provides a background to guide future efforts to design rubber compounds for 3D printing applications.