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Producing ceramic parts by Vat Photopolymerization (VPP) additive manufacture with desired mechanical properties typically requires time‐consuming debinding steps. This study aims at optimizing composition and processing parameters with the use of dibutyl phthalate (DBP) in the resin formulation and debinding in an argon atmosphere for dental zirconia‐toughed alumina (ZTA). The method produces parts with fewer defects, and 67.7% higher flexural strength while increasing the debinding heating rate over 400% compared to standard formulations debinded in air. These improvements are attributed to pore formation at low temperatures and reduced heat release and gas evolution rates arising from use of the DBP and the inert atmosphere, respectively. While ZTA ceramics were studied, this method should be applicable to many ceramic systems with exciting possibilities for promoting the rapid development of VPP 3D‐printed high‐performance ceramics for various engineering applications. [ABSTRACT FROM AUTHOR]

Carbon fiber‐reinforced composites are widely used in aerospace, rail transportation, and new energy vehicles due to their small specific gravity as well as good mechanical and chemical properties. Additive manufacturing of continuous carbon fiber‐reinforced polymer composites is an innovative composite manufacturing technique. In this paper, bending and shear specimens with different hatch spacing and layer thicknesses were prepared by fused filament fabrication (FFF) technique and subjected to three‐point bending experiments and interlayer shear experiments, respectively. The results showed that the maximum flexural strength and flexural modulus of the fabricated parts were 383.81 MPa and 41.23 GPa, respectively, and the maximum interlayer shear strength was 13.64 MPa. Finally, an optimized criterion for determining fiber kinking, fiber breakage, and matrix damage was proposed by considering in situ strength variations induced by process parameters. This new model was subsequently validated and could provide a method for fracture predicting of additive manufactured carbon fiber‐reinforced composites. Highlights: CCFRC parts with different porosities were prepared by adjusting the layer thickness and hatch spacing.The bending and interlaminar shear damage mechanisms of CCFRC fabrications are revealed, and the effects of layer thickness and hatch spacing on their mechanical properties are investigated.Introduction of additive manufacturing factors to optimize failure models for CCFRC parts.Introduction of additive manufacturing coefficients to accurately predict the interlaminar shear strength of CCFRC parts by AM. [ABSTRACT FROM AUTHOR]

SiC ceramic lattice structures (CLSs) via additive manufacturing (AM) have been recognized as potential candidates in engineering fields owing to their various merits. Compared with traditional SiC CLSs, SiC triply periodic minimal surface (TPMS) CLSs could possess more outstanding properties, making them more promising for wider applications. Since SiC CLSs are hard to be fabricated through stereolithography techniques because of inferior light performance, the laser powder bed fusion (LPBF) process via selective sintering is an effective method to prepare near‐net‐shaped SiC TPMS lattices. As the mechanical performances of lattice structures are the foundation for future practical applications, it is of great significance to optimize the preparation process, thus improving the mechanical properties of SiC TPMS structures. In this work, the optimal printing parameters of the LPBF and liquid silicon infiltration process for SiC ceramic TPMS CLSs with three different volume fractions were systematically illustrated and analyzed. The effects of the printing parameters and carbon densities on the fabrication accuracy, microstructure, and mechanical performance of SiC TPMS CLSs were defined. The mechanism of the reactive sintering process for the SiC TPMS lattice structure was revealed. The results reveal that Si/SiC TPMS CLSs with optimum preparation have superior manufacturing accuracy (most less than 6%), relatively high bulk densities (about 2.75 g/cm3), low residual Si content (6.01%), and excellent mechanical properties (5.67, 15.4, and 44.0 MPa for Si/SiC TPMS CLSs with 25%, 40%, and 55% volume fractions, respectively). [ABSTRACT FROM AUTHOR]

The solar‐driven interface evaporation is one of the most promising technologies for desalination and wastewater purification. However, in the ebb and flow of the tide, water absorbed in the hydrophilic evaporator bottom would significantly change, leading to the shape deformation of the system and further failure of solar steam generation. Here it is reported that the moisture‐thermal stable and superhydrophilic alumina‐based ceramics can be fabricated by a selective laser sintering (SLS) 3D printing strategy. The printed alumina‐based ceramics possess superhydrophilicity. Along the side surface of the printed sample, a 5 µL water droplet can be fast absorbed in 14 ms. Most importantly, they can maintain stable and high evaporation efficiency even after being dried out for ten times, demonstrating the excellent physical resistance to continuous moisture‐thermal transition. Finally, the "I‐shaped" evaporators are printed with salt‐resistant ability, which can maintain a steady high evaporation efficiency in seawater and 20 wt% brine for long‐term steam generation process. The moisture‐thermal stable alumina‐based ceramics prepared in this work will provide inspiration for stable solar steam generation materials, and expand the development of 3D printing functional materials. [ABSTRACT FROM AUTHOR]

Manufacturing abrasion‐resistant superhydrophobic matters is challenging due to the fragile feature of the introduced micro‐/nanoscale surface roughness. Besides the long‐term durability, large scale at meter level, and 3D complex structures are of great importance for the superhydrophobic objects used across diverse industries. Here it is shown that abrasion‐resistant, half‐a‐meter scaled superhydrophobic objects can be one‐step realized by the selective laser sintering (SLS) 3D printing technology using hydrophobic‐fumed‐silica (HFS)/polymer composite grains. The HFS grains serve as the hydrophobic guests while the sintered polymeric network provides the mechanical strength, leading to low‐adhesion, intrinsic superhydrophobic objects with desired 3D structures. It is found that as‐printed structures remained anti‐wetting capabilities even after undergoing different abrasion tests, including knife cutting test, rude file grinding test, 1000 cycles of sandpaper friction test, tape test and quicksand impacting test, illustrating their abrasion‐resistant superhydrophobic stability. This strategy is applied to manufacture a shell of the unmanned aerial vehicle and an abrasion‐resistant superhydrophobic shoe, showing the industrial customization of large‐scale superhydrophobic objects. The findings thus provide insight for designing intrinsic superhydrophobic objects via the SLS 3D printing strategy that might find use in drag‐reduce, anti‐fouling, or other industrial fields in harsh operating environments. [ABSTRACT FROM AUTHOR]

Multi‐material additive manufacturing has become a promising trend in fabricating advanced functional architectures due to its controllable design of diverse material species and novel structures. It remains challenging to endow the multi‐material components with a mechanical‐to‐electrical conversion capability. This study reports on multi‐material selectively laser sintered magnetoelectric architectures that can convert mechanical energy to electricity in a structure‐dependent manner. The principal aim is to establish a relationship between the electrical output and the printed structures by fabricating a series of porous architectures with diverse structural parameters. The findings show that the output voltage increases with the decrease of the elastic modulus and the increase of the magnetic height, which has been analyzed by numerical simulation. Owing to the mechanical‐to‐electrical conversion capability, a pair of multi‐material printed sneakers with the functionalities of power generation and gait analysis has been prepared. The voltage output reaches as high as ≈2 V, which can lighten a light‐emitting diode lamp when a user is running. The described solution in this work has offered an exploration framework for the design, fabrication, and application prospects of multi‐material additively manufactured architectures. [ABSTRACT FROM AUTHOR]

Inspired by shape‐morphing organisms in nature, researchers have developed various hydrogels with stimuli‐responsive swelling, shrinking, bending, folding, origami, rolling, twisting, or locomotion. These smart hydrogels are usually created by patterning or 4D printing. The shape morphing of hydrogels allows the fabrication of helixing, twisting, and rolling microstructures, all of which are hard to reproduce directly by ordinary techniques. More importantly, under external stimuli (e.g., solvent, humidity, temperature, light, pH, and electric/magnetic fields), many hydrogels exhibit recoverable shape morphing and thus find promising applications in grippers, sensors, valves, soft robotics, etc. Since shape morphing determines the functions of hydrogels in a great number of cases, herein, recent advances of stimuli‐responsive hydrogels are summarized, with their types, shape‐morphing mechanisms, fabrication methods, shape‐morphing modes, and extensive applications covered. The conclusion and perspectives are also presented to guide the design and fabrication of functional hydrogels. [ABSTRACT FROM AUTHOR]

Sustainable energy supply by converting mechanical to electric energy is critical for flexible electronic technologies, soft robots, and biomedical applications. The development of magnetoelectric conversion approaches requires new strategies with lightweight, small, and portable features. To address this need, an underwater magnetic nanofluid droplet‐based generator (UMNDG) is designed to convert the mechanical energy of sliding droplets to electricity. The UMNDG consists of four parts: 3D‐printed underwater superoleophobic surface bioinspired by shark skin, oily magnetic nanofluid droplets, bottom coil, and magnetic part. By improving the manufacturing parameters of 3D‐printed shark skin, underwater superoleophobic and low‐adhesion surfaces can be fabricated, allowing for the magnetic nanofluid droplets to slide upon the surfaces freely. When the magnetic nanofluid droplets slide/leave the bottom coil/magnet region, the magnetic flux passes through the coil changes, yielding the generation of electricity. Maxwell simulation is used to study related working mechanism. Finally, a ladder‐type setup consisting of four UMNDGs is assembled in series, enabling to trigger the lighting of a LED bulb by continuous sliding of magnetic nanofluid droplets. Such a setup design may find use in a wide range of applications, from flexible electronic technologies to bio‐inspired materials that interface with magnetic nanofluid systems. [ABSTRACT FROM AUTHOR]

Integrated sensor–actuators with exciting functionalities, such as action self‐sensing, position self‐sensing, posture self‐sensing, or active sensing, are promising for applications in biomedical device, human–machine interaction, intelligent self‐protection devices, and humanoid robots. Despite recent progress, it remains challenging to achieve a macroscopical integrated sensor–actuator in a material system with microstructures. To address this critical challenge, a 4D printing bioinspired microstructure strategy is reported to design a high‐performance integrated sensor–actuator capable of simultaneous actuation and sensation. Decoupled thermal stimulation and strain sensation is achieved by combining nanocarbon black/polylactic acid composites with bioinspired gradient microgap structures. As a result, printed integrated sensor–actuators can actively touch objects triggered by thermal stimulation and self‐sense the touching state through the resistance change. It is anticipated that the basic design principle underlying this behavior can be used to develop integrated sensor–actuators of various shapes and functionalities to meet desirable applications. [ABSTRACT FROM AUTHOR]

4D printing is a newly emerging technique that shows the capability of additively manufacturing structures whose shape, property, or functionality can controllably vary with time under external stimuli. However, most of the existing 4D printed products only focus on the variation of physical geometries, regardless of controllable changes of their properties, as well as practical functionality. Here, a material combination concept is proposed to construct 4D printed devices whose property and functionality can controllably vary. The 4D printed devices consist of conductive and magnetic parts, enabling the integrated devices to show a piezoelectric property even neither part is piezoelectric individually. Consequently, the functionality of the devices is endowed to transfer mechanical to electrical energy based on the electromagnetic introduction principle. The working mechanism of 4D printed devices is explained by a numerical simulation method using Comsol software, facilitating further optimization of their properties by regulating diverse parameters. Due to the self‐powered, quick‐responding, and sensitive properties, the 4D printed magnetoelectric device could work as pressure sensors to warn illegal invasion. This work opens a new manufacturing method of flexible magnetoelectric devices and provides a new material combination concept for the property‐changed and functionality‐changed 4D printing. [ABSTRACT FROM AUTHOR]

Removing heavy metal (loid) s (HMs) from contaminated soil in a nonselective, highly efficient, and energy‐free manner is a major global challenge. Herein, this work synthesizes and assembles a biomimetic materials system (BMS) consisting of an artificial plant, a hemispherical glass cover, and a reflective plate, capable of non‐selective and highly efficient remediation of soil contaminated by various HM ions under sunlight. Specifically, a water cycle is driven to establish between the soil, artificial plant, and atmosphere by solar energy in the BMS, which induced water‐soluble HM ions to enrich and precipitate at the top edge of the artificial plant. The formed HM precipitate is easily removed, contributing to the extremely strong recyclability of BMS. This system has significant advantages in terms of soil properties, contamination characteristics, energy consumption, processing time, and removal amount over other representative remediation methods, demonstrating its great potential for practical application in the remediation of various HM‐contaminated soils. [ABSTRACT FROM AUTHOR]