A Ti(C,N)-(W,Ti)C-MoC/Ti(C,N)-(W,Ti)C-Al2O3n/PZT laminated ceramic cutting tool integrating cutting and force measurement functions with piezoelectric effect was designed and fabricated. The composition of laminated ceramic layer was designed on the basis of concept of residual thermal stress toughening mechanism. The effects of sintering temperature and layer thickness ratio on microstructure, mechanical properties and piezoelectric coefficient of the laminated ceramic were investigated. The layer thickness ratio primarily influenced the laminated ceramic properties by changing the residual thermal stresses distribution. A layer thickness ratio of 0.33 was an optimal value. When the layer thickness ratio was 0.33 and the sintering temperature was 950 degrees C, the laminated ceramic had good properties including the flexural strength, fracture toughness, Vickers hardness and piezoelectric coefficient with a value of 607 f 30 MPa, 7.8 f 0.2 MPa m1/2, 19.8 f 0.3 GPa and 69 f 5 pC/ N respectively. The sintering temperature had little effect on the grain size of T1 and T2 layer ceramics, and mainly affected the ceramic properties by changing the grain fracture mode. The T3 layer ceramic grain size increased with an increase in sintering temperature. The larger grain size improved polarization efficiency and ceramic piezoelectric property. Moreover, the force measurement function of the laminated ceramic cutting tool was validated by comparing the measured output voltage with the cutting forces obtained from finite element simulations and those calculated using the Kienzle cutting force model.

The formulation of photosensitive SiC slurry with high solid loading, low viscosity, and long-term stability remains a critical challenge. Here, a triblock copolymer of Poly(ethylene glycol)-block-poly (propylene glycol)-block-poly (ethylene glycol) (PEG-PPG-PEG) was employed for the first time as a kind of dispersant to modulate the wettability of SiC particle surfaces through hydrogen-bonding anchoring interactions. The results demonstrate that with the addition of 6 wt% PEG-PPG-PEG, the slurry viscosity reaches a minimum, and the retained sedimentation height after 96 h is as high as 86%, indicative of pronounced shear-thinning behavior and excellent long-term stability. Furthermore, fine SiC particles were incorporated to construct a bimodal particle size distribution system, and the effects of particle size distribution on slurry stability, rheological properties, and photosensitive properties were systematically investigated. A predictive model for cure depth was accordingly established. The resulted SiC slurry exhibits a solid loading of 75 wt%, a viscosity of 4.40 Pa·s at a shear rate of 50 s−1, less than 12% sedimentation height after 60 days, and a single-layer cure depth exceeding 100 μm. Through the optimized debinding and liquid silicon infiltration (LSI) processes, the fabricated SiC ceramic achieves a density of 2.76 ± 0.01 g/cm3, a flexural strength of 198.21 ± 5.04 MPa, and a Vickers hardness of 27.95 ± 1.66 GPa. A honeycomb-structured space mirror printed using the bimodal slurry exhibits superior surface quality after polishing and delivers clear, undistorted imaging. This work provides a novel strategy and theoretical foundation for enhancing the printability of high-solid-loading SiC slurry.

Vat photopolymerization additive manufacturing (VPP‐AM) technology has emerged as a pivotal technology for the precision manufacturing of advanced ceramics, owing to its unique design freedom, superior manufacturing accuracy, and excellent surface quality. However, traditional homogeneous single‐material ceramic components have revealed functional limitations, driving the transition of ceramic VPP‐AM from single‐material systems to multimaterial composite architectures. Multimaterial VPP‐AM enables the integrated fabrication of diverse ceramic materials, thereby producing components with comprehensive properties. Although various literature has reviewed VPP‐AM of single‐material ceramics, a summary regarding manufacturing strategies, cleaning mechanisms, and applications of multimaterial ceramics remains lacking. This review systematically summarizes the preparation strategies, applications, and recent advances in VPP‐AM for single‐material and multimaterial ceramic fabrication. Photopolymerization forming principles of ceramic components and their innovative applications for six representative single‐material ceramics VPP technologies are analyzed and discussed. Three core multimaterial ceramic manufacturing strategies, such as switching vat, dynamic fluidic control, and VPP hybridization are comprehensively elucidated. Cleaning methods and multimaterial interface design strategies are also introduced in detail. Prospective outlooks are provided regarding the existing technical bottlenecks and future development directions for multimaterial ceramic VPP‐AM, offering technical insights for the innovative design of high‐performance multifunctional composite ceramic devices.

The fabrication of porous Si3N4/BN ceramics for high-temperature radomes via vat photopolymerization is hindered by excessive slurry viscosity, which restricts the recoating process, and by limited curing depth. To overcome these challenges, we developed a high-performance slurry using a synergistic strategy combining BN surface functionalization with optical modulation via SiO2. Ultrasonic-assisted hydrolysis and silane coupling significantly enhanced interfacial compatibility with the resin, reducing viscosity from 20.83 to 4.51 Pa & sdot;s at a shear rate of 30 s- 1. Simultaneously, the incorporation of refractive-index-matched SiO2 effectively suppressed light scattering, thereby increasing curing depth and structural integrity. Furthermore, SiO2 regulated liquidphase behavior during sintering to optimize the microstructure. The resulting ceramics exhibited an exceptional property balance: 42.14 % porosity, 68.2 MPa flexural strength, a dielectric constant of 2.56, and a loss tangent of 6.85 x 10-3. These metrics satisfy the stringent requirements for wave-transparent applications, offering a robust pathway for manufacturing complex-shaped components.

Balancing high solid loading, low viscosity and dispersion stability is essential for photocurable ceramic slurries. A stability-constrained framework was developed for bimodal alumina (Al₂O₃) slurries by relating adsorbed-layer thickness to interparticle interactions and effective volume fraction. The model revealed that coarse particles benefit from thicker steric layers to resist van der Waals aggregation, whereas nanoparticles are more sensitive to adsorbed-layer-induced excluded-volume amplification and therefore benefit from thinner layers. These contrasting effects motivated a particle-size-selective dispersant strategy, in which thicker-layer-forming dispersants were assigned to coarse particles and thinner-layer-forming dispersants to nanoparticles. Based on this strategy, a 70vol% bimodal Al₂O₃ slurry achieved a viscosity of 1.95Pa·s at 80s⁻¹, low thixotropic hysteresis, and continuous recoating. The sintered ceramics exhibited a dense microstructure and a flexural strength of 211MPa. This work provides a mechanistic framework for understanding the rheology–stability trade-off in the investigated bimodal alumina system.

High-solid-loading ceramic vat photopolymerization (VPP) enables dense ceramic components, but dimensional control remains difficult because particle-induced scattering redistributes exposure energy and alters curing geometry. Existing working-curve descriptions, simplified scattering models, and empirical compensation schemes provide only limited predictive connection between slurry optical characteristics and printed feature dimensions when dependent scattering becomes significant. Here, a coupled multiple-sphere T-matrix and Monte Carlo ray-tracing (MSTM-MCRT) approach was developed for curing-geometry prediction and contour compensation. Full-wave MSTM calculations were used to obtain dependent-scattering radiative properties, including scattering, absorption, and angular redistribution, for dense particle assemblies. These properties were then incorporated into a three-dimensional MCRT model to predict spatial dose distribution, cure depth, cure width, and cross-sectional curing contour. The predicted curing dimensions were further converted into local boundary offsets for model-guided compensation of contour-defined microfeatures and internal channels. For the investigated Al2O3-resin slurry over 10-50 vol% solid loading, comparison with independent-scattering approximation and structure-factor approximation baselines shows that the advantage of MSTM becomes especially evident at Phi >= 40 vol%. Experiments showed that the predicted cure depth and cure width remained within the +/- 5% reference band in the relative error analysis. The approach also compensated square openings, circular openings, and a serpentine microchannel, yielding a 791 & micro;m opening for an 800 & micro;m target. This study establishes a physics-based route from dense-particle optical response to curing-geometry prediction and contour compensation, providing guidance for exposure design, slurry-formulation assessment, and dimensional control in high-solid-loading ceramic VPP.

High solid loading of ceramic slurries is critical for stereolithography 3D printing, but it often leads to excessive viscosity and poor printability. This study proposes a synergistic strategy combining dielectric barrier discharge (DBD) plasma hydroxylation with particle gradation optimization to prepare a hydroxyapatite/beta-tricalcium phosphate/alumina (HA/beta-TCP/Al2O3) ceramic slurry with a solid loading of 57 vol% and a viscosity of 5.2 Pa & sdot;s at 30 s-1. DBD plasma processing enhances surface activation of particles under solvent-free conditions, while particle gradation optimization via D-optimal design and response surface methodology regulates slurry rheology. The HA/beta-TCP/Al2O3 multiphase bioceramics were fabricated by stereolithography 3D printing and achieved a compressive strength of 35.5 MPa and an elastic modulus of 36 GPa after sintering at 1200 degrees C, meeting load-bearing requirements of human cancellous bone. In vitro cell experiments confirmed the biocompatibility, proliferation promotion, and cell-adhesive properties of scaffolds. The work tackles the challenge of optimizing solid loading and rheological properties, providing a generalizable strategy for optimizing high-solid-loading slurries in the additive manufacturing of functional ceramics.

The ceramic material Silicon carbide (SiC) has significant potential for applications in stereolithography apparatus (SLA) manufacturing technology. Nevertheless, SiC ceramic composites are severely limited in their applications due to their high absorption. In this paper, a surface modification process for the sol-gel method is discussed. The Al2O3 coating layer was successfully coated on the surface of SiC particles and the effect of alumina coating amount on the material properties was systematically investigated. By combining Bruggeman's effective medium theory model analysis, the regulation mechanism of the coating layer on its light scattering behavior was verified. Experimental and model analysis demonstrated that the Al2O3 coating effectively reduces the absorbance and viscosity of SiC ceramic materials while significantly enhancing the curing thickness and solids content of the ceramic slurry through the SLA process. Both the theoretical model and experimental data showed a consistent decrease in the extinction coefficient, confirming the coating layer's inhibitory effect on light absorption. When the solid content of the ceramic slurry was 72 wt%, the viscosity of the slurry was 0.84 Pa·s (shear rate of 30 s-1), and the curing thickness of the monolayer was 153 ± 10 μm. The final SiC ceramic composites, with a density of 2.67 g/cm3 and an average flexural strength of 44.7 ± 1.9 MPa, were obtained after degreasing and sintering. In this research, a novel approach is developed for the broad application of non-oxide ceramic composites, such as SiC fabricated by SLA, thereby paving the way for their expanded use.

ABSTRACT The formulation of photosensitive SiC slurry with high solid loading, low viscosity, and long‐term stability remains a critical challenge. Herein, a triblock copolymer of poly(ethylene glycol)–block–poly(propylene glycol)–block–poly(ethylene glycol) (PEG–PPG–PEG) was employed as a kind of dispersant to modulate the wettability of SiC particle surfaces through hydrogen‐bonding anchoring interactions. The results demonstrate that with the addition of 6 wt % PEG–PPG–PEG, the slurry viscosity reaches a minimum, and the retained sedimentation height after 96 h is as high as 86%, indicating pronounced shear‐thinning behavior and excellent long‐term stability. Furthermore, fine SiC particles were incorporated to construct a particle size grading system, and the effects of particle size grading on slurry stability, rheological properties, and photosensitive properties were systematically investigated. Through the optimized debinding and liquid silicon infiltration (LSI) processes, the fabricated SiC ceramic achieves a density of 2.76 ± 0.01 g/cm 3 , a flexural strength of 198.21 ± 5.04 MPa, and a Vickers hardness of 27.95 ± 1.66 GPa. A honeycomb‐structured space mirror, printed using the bimodal slurry, exhibits superior surface quality after polishing and delivers clear, undistorted imaging. This work provides a novel strategy and theoretical foundation for enhancing the printability of high‐solid‐loading SiC slurry.

Ti(C,N)-WC-TiSi2 homogeneous cermet tool materials (TS20) and Ti(C,N)-(W,Ti)C-TiSi2 five-layer gradient cermet tool materials (GT5) were fabricated via vacuum hot pressing sintering technology. The high-temperature mechanical properties, thermal shock resistance, and thermal fatigue resistance of TS20 and GT5 were investigated. The results indicated that in the range of 600-800 degrees C, the glass-phase oxides formed by silicide oxidation in both cermet materials filled and healed microcracks, thereby increasing their flexural strength and fracture toughness. Above 900 degrees C, excessive oxidation produced microcracks and hole defects, leading to a rapid drop in their flexural strength and fracture toughness. The residual compressive stress in the surface material of GT5 caused by the gradient structure was conducive to alleviating the thermal stress gradient, thus resulting in a higher critical thermal shock temperature difference for GT5 than for TS20. GT5 exhibited a more tortuous crack propagation path than TS20, and the propagation of its thermal fatigue cracks required more energy. The theoretical results of the stress intensity factor at the crack tip revealed that under the same thermal shock, the critical thermal fatigue crack length in GT5 was longer than that in TS20 when unstable crack propagation occurred.

A brain-mimetic scaffold that merges fractal cortex topology with hierarchical perfusion channels was fabricated to sustain a high viability in thick neural constructs. An 8% (w/v) methacrylated gelatin (GelMA)/2% (w/v) methacrylated hyaluronic acid/1% (w/v) methacrylated silk fibroin/3% (w/v) gelatin hydrogel supporting NE-4C neural stem cell proliferation, adhesion, and Digital Light Processing (DLP) bioprinting was developed. Human-brain computed tomography (CT) data were reconstructed, and box-counting verified folded fractal geometry (D = 1.35-1.37). A perfusable hollow scaffold with a wall thickness of 1.5 mm and interconnected channels was accordingly designed and printed in one step by alternating batch exposure with on-demand resin replenishment. After 28 days of static culture, viability reached 92.8%; this high cell survival rate was primarily attributed to the scaffold's fractal topological structure. A closed-loop perfusion system was established for the brain-like scaffold. Closed-loop perfusion speed at 2 mL/min further improved viability by 6% and proliferation by 14%, whereas perfusion at 8 mL/min decreased them by 25% and 6%. This investigation provides a scalable biomimetic platform for constructing functional neural organoids, screening neurotoxic drugs, and repairing personalized brain tissue repair.

To enable the simultaneous prediction of flexural strength and thermal expansion coefficient (TEC) in ceramic composites, a coupled model based on Eshelby’s equivalent inclusion theory and Mori-Tanaka homogenization scheme is established for two-phase composites. The flexural strength model accounts for matrix damage, interfacial debonding, and particle fracture, while the TEC model explicitly includes the interphase. Si3N4/MAS (cordierite) composites containing 5–25 vol.% MAS were fabricated by vacuum hot-press sintering for validation. The effects of MAS content on the phase composition, microstructure, relative density, and mechanical properties of the composites were investigated. The model predicts a feasible MAS content range of 18.5–24.5 vol.% under the coupled constraints of a minimum predicted flexural strength of 500 MPa and a maximum predicted TEC of 3.0 × 10-6 °C-1. Among the tested composites, the composite containing 20 vol.% MAS exhibits the best overall balance of relative density, Vickers hardness, fracture toughness, flexural strength, and TEC, with the first four properties reaching 99.03 ± 0.12%, 14.99 ± 0.08 GPa, 6.03 ± 0.16 MPa·m1/2, and 493.67 ± 47.62 MPa, respectively. XRD and SEM analyses indicate that an appropriate MAS addition promotes partial α→β phase transformation, densification, and the formation of elongated β-Si3N4 grains. The enhanced properties are mainly attributed to residual compressive stresses induced by thermal mismatch, together with crack deflection, interfacial debonding, grain bridging, and grain pull-out mechanisms. The proposed model provides theoretical guidance for the design of ceramic composites with high flexural strength and low TEC.

Cerebral cortex models hold significant promise for research and treatment of neurological diseases. However, their complex architecture and low elastic modulus present persistent challenges that existing fabrication methods struggle to address effectively. In this study, a fabrication strategy for cortical-mimetic models is developed, utilizing extrusion printing combined with immersion curing technology to successfully produce a biomimetic structure that achieves both a low elastic modulus and high structural stability. The model consists of two functional components. The inner layer comprises linear structures printed by cell-laden hydrogels, which are formed via temperature-sensitive and ionic crosslinking, endowing them with excellent cytocompatibility and an elastic modulus similar to that of native brain tissue. The outer supportive structure forms a covalently crosslinked network through photocuring, providing high structural stability to the model while maintaining sufficient porosity for efficient nutrient diffusion and exchange. Long-term in vitro culture experiments demonstrated that the printed structure exhibited stability, with cells showing robust viability and directional growth patterns. These findings indicate that the engineered cortical-mimetic model possesses superior mechanical stability and sustained cellular vitality, offering a promising strategy for efficient bioprinting of complex soft tissues.

To overcome the challenge of accurately measuring transient high temperatures at the tool-chip interface, this study uses a self-developed N-type ZrB2-based thermoelectric temperature-measuring tool. It aims to investigate the effects of ZrO2content and the integrity of the electrode interface on temperature measurement performance and mechanical properties. Samples with designated ZrO2contents (C202505, C202510, C202515) were prepared via vacuum hot-pressing and subsequently characterized through thermoelectric testing, interfacial mechanical analysis, microscopy, and wear experiments. The results show that the thermoelectric potential-temperature relationship for the C202515 sample exhibits significant anomalies. Experimental analysis confirms that the bonding performance at the joint interface is a critical factor governing temperature measurement stability. A mismatch in the CTE between the Positive and Negative electrode materials induces microdefects at the interface, which reduces the interfacial bonding strength. This degradation, in turn, increases the interfacial contact resistance and ultimately destabilizes the temperature measurement signal. This study is the first to establish correlations between temperature measurement performance, interfacial mechanics, and wear resistance. It identifies an optimal thermal expansion difference (Delta CTE <= 0.5 & times; 10-6/degrees C) and thereby provides crucial guidance for developing stable and reliable thermoelectric ceramic tools.

In the field of nuclear power, deep hole drilling is a key process, and its processing accuracy, hole quality and efficiency are of vital importance. The study aims to investigate the drill wear during BTA deep hole processing of tube sheet heterogeneous materials and its influence on surface integrity. Results show that under the given cutting parameters, the wear degree of the external insert of the three cutting insert is the highest. Additionally, multiple drill wear mechanisms are simultaneously activated, forming a mechanochemical coupling-induced system predominantly governed by abrasive wear, adhesive wear, and oxidative wear. Moreover, the impact of drill wear on surface integrity is manifested in the following aspects. Under the influence of drill wear, the surface roughness of SA508Gr.3Cl.2 steel first decreases and then gradually increases, while the Inconel 690 alloy shows a gradual decrease in surface roughness. More severe drill wear leads to an increase in thermal mechanical loads, resulting in a thicker surface deformation layer, smaller residual compressive stress, and a thicker work-hardening layer. The spindle torque during the drilling process was collected, and the microstructure of the weld fusion zone before and after the machining was characterized to explain the causes of the formation of surface integrity on heterogeneous materials. These results have enriched the research in the field of BTA deep hole drilling.

This study addresses the challenge of controllable fabrication of superhydrophobic micro-nano structures on monocrystalline silicon and other hard brittle materials using laser processing. Building upon our previously developed two-step laser fabrication method for hierarchical micro-nano structures (see main text), we established a thermodynamic contact angle model incorporating multiscale morphological features. First coupling of exponential and sine functions precisely describes laser-induced periodic surface structures (LIPSS) cross-section profiles across femtosecond laser incident angles, improving contact angle model. Systematic experimental validation confirmed the model's high reliability, with relative prediction errors (compared to experimental measurements) within f 1.02 %. Key findings include: (1) The droplet exhibits a composite Cassie-Baxter state on the micro-nano structured surface; (2) The aspect ratio (defined as the depth-to-width ratio) of V-grooves plays a decisive role in contact angle enhancement, while width variation under fixed aspect ratio shows negligible influence. Through model-guided optimization, we identified optimal structural parameters (aspect ratio 0.836, width 40 mu m), achieving exceptional superhydrophobic performance with a contact angle of 163.7 f 0.82 degrees and a rolling angle of 2.62 f 0.06 degrees. Experimental results confirmed coverage of the theoretical optimum. This model provides reliable theoretical guidance for laser-fabricated superhydrophobic surfaces, and its multiscale analysis methodology offers valuable references for designing other functional surfaces.

Severe skin injuries require printable biomaterials that combine tissue adhesion, infection-control potential, and wound-repair compatibility. In this study, a gelatin/tannic acid/hyaluronic acid/elastin hydrogel precursor was developed using a rheology-directed design strategy for extrusion-based 3D printing. Rheological tests showed that the precursor ink exhibited controllable shear-thinning behavior, thixotropic recovery, and yield-stress characteristics suitable for extrusion at 25 °C, which corresponds to the ambient printing environment rather than physiological temperature. EDC/NHS secondary crosslinking was introduced to improve post-printing structural stability; however, the rheological stability of the post-crosslinked network at physiological temperature, approximately 37 °C, requires further systematic evaluation. The optimized formulation showed tissue adhesion,in vitrobacteriostatic activity againstE. coliandS. aureus, and preliminary wound-closure potential in a non-infected mouse wound model. These results suggest that rheology-directed formulation design may support the development of printable bioadhesive hydrogel dressings, while further studies are needed to validate post-crosslinked mechanical stability, post-printing cell viability, and infection-control efficacy in infected wound models.

Picosecond laser ablation of monocrystalline silicon involves ultrafast electron excitation, electron-lattice energy transfer and nonequilibrium material removal, making it difficult to accurately identify the removal mechanisms and clarify their transition using conventional molecular dynamics simulations. In this study, an electron-density-dependent two-temperature model coupled with molecular dynamics (n-TTM-MD) model is developed to investigate the material removal mechanisms of monocrystalline silicon under picosecond laser irradiation. The results show that free-electron-density evolution drives laser energy deposition from deep volumetric heating to surface-localized heating, thereby altering the ablation behavior. Material removal evolves continuously from stress-driven spallation to thermally driven phase explosion, with spallation and phase-explosion thresholds identified as 0.58 and 0.65 J/cm2, respectively. The simulated ablation threshold and crater profile agree well with experimental measurements, and the laser-fluence-dependent removal behavior is consistent with the observed crater morphology evolution. This study provides atomistic insight into the physical origins and transition of removal mechanisms during picosecond laser ablation of monocrystalline silicon and offers guidance for controlling material removal in high-quality laser micromachining.