Ceramic Precursors Research Articles

Polyborosilazanes with Controllable B/N Ratio for Si-B-C-N Ceramics.

Polyborosilazanes with controllable B/N ratio were synthesized using high-boron-content m-carborane, dichloromethylsilane, and hexamethydisilazane. After high-temperature pyrolysis, Si-B-C-N quaternary ceramics with SiC and B4C as the main phases were obtained. The B/N ratio in the precursors corresponded to the change in the feeding ratio of carborane and dichloromethylsilane. The effects of boron content and B/N ratio on the ceramic precursors and microphase structure in Si-B-C-N quaternary ceramics were explored in detail through a series of analytical characterization methods. A high boron content results in a significant increase in the ceramic yield (up to 71 wt%) of polyborosilazanes, and at the same time, the B/N molar ratio was regulated from 28.4:1 to 1.62:1. The appearance of the B4C structure in the Si-B-C-N quaternary ceramics through the regulation of the B/N ratio, has rarely been reported.

Effects of hafnium sources and hafnium content on the structures and properties of SiBNC–Hf ceramic precursors

AbstractThe synthesis of SiBNC–M (M is metal element) multinary ceramic precursors has mainly been through chemical modification of the SiBNC ceramic precursors with the introduction of the metal element/compound. This misses the simplicity, efficiency, and combined benefits of single reactor synthesis routes. We herein adopt a one‐pot method to synthesize SiBNC–Hf ceramic precursors (PBSHZ) from different Hf sources, and with varying Hf content. The starting materials include hafnium tetrachloride, hafnium dichloride, trichlorosilane, hexamethyldisilazane, and boron trichloride. Fourier transform infrared spectroscopy (FT‐IR), nuclear magnetic resonance (NMR), X‐ray photoelectron spectroscopy (XPS), and thermogravimetric analysis are employed to characterize the structures and properties of the PBSHZ. The results reveal the successful incorporation of Hf into the precursors. Compared to the hafnium tetrachloride source, the precursor synthesized from hafnium dichloride yields more ceramics and shows better solubility, due to fewer Hf–Cl bonds available for reaction. Meanwhile, there is a positive correlation between the rise in the Hf content of PBSHZ and the ceramic yield. However, the solubility and processability of the precursors decline, due to the multiplication of the cross‐linking degree in the molecular structure. Further FT‐IR, NMR, XPS, and thermogravimetry–mass spectrometry (TG–MS) analysis indicate a full polymer‐to‐ceramic transformation at 1000°C pyrolysis temperature. At this point, the SiBNC–Hf ceramics mainly consist of an Si–B–N skeleton, HfN, and free carbon.

Polymer precursor synthesis of novel ZrC–SiC ultrahigh-temperature ceramics and modulation of their molecular structure

In this study, ZrC–SiC composite ceramics were prepared with varying Zr/Si molar ratios using sol–gel method. Composites were characterized by Fourier-transform infrared spectroscopy (FT–IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman spectroscopy, and energy-dispersive X-ray spectroscopy (EDS). FT–IR analysis confirmed macromolecular network structure of composites, in which the precursor is composed of polyvinyl butyral (PVB) as main chain, silane molecules are interlinked via –OH moieties in PVB side chains, and Zr atoms are crosslinked with Si in corresponding proportion. Ceramic precursor begins to decompose at a temperature exceeding 1300 °C and is completely transformed into ZrC–SiC composite ceramics with corresponding Zr/Si molar ratio at 1600 °C. Raman spectroscopy and TEM results reveal that after annealing at 1600 °C, ZrC powder uniformly covers surface of SiC ceramics, and high-crystallinity graphite carbon covers ZrC powder.

Enhanced Electromagnetic Wave Absorption of SiOC/Porous Carbon Composites.

Carbon-based materials have been widely explored as electromagnetic (EM) wave absorbing materials with specific surface areas and low density. Herein, novel porous carbon/SiOC ceramic composites materials (porous C/sp-SiOC) were prepared from the binary mixture, which used the low cost pitch as carbon resource and the polysilylacetylene (PSA) as SiOC ceramic precursor. With the melt-blending-phase separation route, the PSA resin formed micro-spheres in the pitch. Then, numerous SiOC ceramic micro-spheres were generated in porous carbon matrices during the pyrolysis process. By changing the percent of SiOC, the microstructure and wave absorption of porous C/sp-SiOC composites could be adjusted. The synergistic effect of the unique structure, the strong interfacial polarization, and the optimized impedance matching properties contributed to the excellent absorption performance of porous C/sp-SiOC composites. The minimum reflection loss for porous C/sp-SiOC absorber reached -56.85 dB, and the widest effective bandwidth was more than 4 GHz with a thickness of only 1.39 mm. This presented research provides an innovative and practical approach to developing high-performance porous carbon-based microwave absorption materials from green chemistry.

Lightweight and geometrically complex ceramics derived from 4D printed shape memory precursor with reconfigurability and programmability for sensing and actuation applications

There is growing interest in additive manufacturing (AM) of ceramics due to the feasibility of achieving geometrically complex shapes for various engineering applications. Polymer-derived ceramics (PDCs), pyrolyzed from polymeric ceramic precursors, act as a competitive material for ceramic AM with advantages such as easy processability, flexible designability, and relatively low sintering temperature. However, the functionality of preceramic polymers is far from being fully exploited, thus restricting the development and applications of 3D printed ceramics. Herein, a novel multifunctional preceramic polymer composite with reconfigurability and shape memory effect is synthesized. By tuning the material compositions, the precursor inks suitable for 4D printing are pyrolyzed into lightweight self-shaping ceramics, allowing complex geometries to be fabricated. The preceramic polymers undergo a stepwise partial-to-full crosslinking process to form interpenetrating polymer networks, resulting in reconfigurability where the as-printed parts can be transformed into shapes with higher complexity. Unlike traditional precursors with static shapes, the precursor here possesses shape memory capability (Tg ∼ 95 °C). During the sintering process, the 3D printed precursor could successively undergo programmable active shape transformation with a high recovery ratio (∼100 %) and pyrolysis conversion into lightweight ceramics (1.05 g/cm3). By exploring the semiconducting behavior of resulting ceramics, temperature sensors leveraging the advantages of reshaping are designed to detect the surface over a wide range (25–750 °C) with good conformability. The development of 4D printed reconfigurable and programmable precursors for the construction of complex ceramics enriches both the complexity and self-shaping capability of ceramics, allowing them to be applied as smart thermistors and deployable structures.

Experimental Investigations into the Pyrolysis Mechanism and Composition of Ceramic Precursors Containing Boron and Nitrides with Different Boron Contents

In this work, a novel ceramic precursor containing boron, silicon, and nitrides (named SiBCN) was synthesized from liquid ceramic precursors. Additionally, its pyrolysis, microstructure, and chemical composition were studied at 1600 °C. The results showed that the samples with different boron contents had similar structural composition, and both of the two precursors had stable amorphous SiBN structures at 1400 °C, which were mainly composed of B-N and Si-N and endowed them with excellent thermo-oxidative stability. With the progress of the heating process, the boron contents increased and the structures became more amorphous, significantly improving the thermal stability of the samples in high-temperature environments. However, during the moisture treatment, the introduction of more boron led to worse moisture stability.

SiOC Phase Control and Carbon Nanoribbon Growth by Introducing Oxygen at Atom Level for Lithium-Ion Batteries.

Poor intrinsic conductivity and the presence of irreversible lithiation phase affect the electrochemical performance of silicon oxycarbide anode materials. Even though it can be improved by increasing free carbon content or composition, scarification of reversible capacity and initial Coulombic efficiency (ICE) remain as challenge. Here, polycarbosilane (PCS) with alternating distribution of silicon and carbon atoms is employed as precursor of SiOC ceramics. Air oxidation cross-linking is used to regulate the content of oxygen and carbon elements in PCS at atom level, so as to explore a solution to improve the intrinsic conductivity and reversible lithium phase content of SiOC ceramics. This strategy provides extremely excellent rate capability, areal/volumetric capacity, and ICE. This is also the first concept for feasible precursor structure design to control the SiOC glass phase and regulate the growth of C nanoribbon that can improve the intrinsic conductivity and reversible capacity of SiOC ceramic anode materials.

In Situ Formation of Nanoparticles on Carbon Nanofiber Surface Using Ceramic Intercalating Agents

Nickel silicide nanoparticles were prepared in situ on carbon nanofibers through pyrolysis of electrospun fibers containing poly(acrylonitrile) (PAN, carbon fiber precursor), silazane (SiCN ceramic precursor), and nickel chloride (nickel source). SiCN ceramics produced in carbon nanofibers during the pyrolysis expanded the graphitic interlayer spacing and facilitated the diffusion of metal atoms to the fiber surfaces, leading to the formation of nickel silicide nanoparticles at a reduced temperature. In addition, nickel silicide nanoparticles catalyzed an in situ formation of carbon nanotubes, with carbon sourced from the decomposition of silazane. The method introduces a simple route to produce carbon supported metal nanoparticles for catalysis and energy storage applications.

Revealing Nanodomain Structures of Bottom-Up-Fabricated Graphene-Embedded Silicon Oxycarbide Ceramics.

Dispersing graphene nanosheets in polymer-derived ceramics (PDCs) has become a promising route to produce exceptional mechanical and functional properties. To reveal the complex nanodomain structures of graphene–PDC composites, a novel reduced graphene oxide aerogel embedded silicon oxycarbide (RGOA-SiOC) nanocomposite was fabricated bottom-up using a 3D reduced graphene oxide aerogel as a skeleton followed by infiltration of a ceramic precursor and high-temperature pyrolysis. The reduced graphene oxide played a critical role in not only the form of the free carbon phase but also the distribution of SiOxC4−x structural units in SiOC. Long-ordered and continuous graphene layers were then embedded into the amorphous SiOC phase. The oxygen-rich SiOxC4−x units were more prone to forming than carbon-rich SiOxC4−x units in SiOC after the introduction of reduced graphene oxide, which we attributed to the bonding of Si atoms in SiOC with O atoms in reduced graphene oxide during the pyrolysis process.

Generative shaping and material-forming (GSM) enables structure engineering of complex-shaped Li4SiO4 ceramics based on 3D printing of ceramic/polymer precursors

Vat photopolymerization (VPP) 3D printing of ceramics normally uses ceramic slurries directly made of the target ceramic powder. It may become challenging when the ceramic powders are difficult-to-make and thus are expensive or rarely accessible. We have previously proposed a generative shaping and material-forming (GSM) 3D printing strategy, which involves the use of low-cost multi-component inorganic ceramic precursors as powder sources. The shaping of complex structures was realized through VPP, followed by reaction sintering to form the target ceramic material. In the current study, as a step further, ceramic (Li 2 CO 3 ) and polymer (methyl polysiloxane) combined precursors were employed as an alternative material source for the first time to go through the 3D printing and reaction sintering processes, complementing the application range of the proposed GSM strategy. The slurry formulation and printability, the sinterability of the printed parts and the microstructures and mechanical performance of the sintered parts were characterized and optimized in accordance with the ingredient contents, particularly the stoichiometric ratios of Si:Li in the precursors. As a result, complex-structured Li 4 SiO 4 ceramics with high purity were fabricated based on the use of Li 2 CO 3 ceramic and Si-rich polymer as precursors. Through the advanced characterization and analysis of material phase and microstructural evolution, it was found that the fabricated complex-structured Li 4 SiO 4 ceramics based on a precursor slurry with a solid content of 40 vol%, a Si:Li ratio of 1:2.5, and a sintering temperature of 850 ℃ showed a high phase purity of 97.23% and a compressive strength of 15.24 ± 0.33 MPa, with a skeleton’s relative density of 65.31% is achieved. The results showed greatly enhanced strength at much higher porosities, which might be advantageous and beneficial to structure engineering for mechanical enhancement and the improvement of tritium release effectiveness. Compared with the previous study using multi-component ceramic powder precursors, the ceramics prepared in this study exhibited enhanced microstructural stability and higher phase purity with an advantageously lower sintering temperature. Further analysis revealed that compared with the high temperature solid-state reaction of multi-component ceramic powder precursors, the involvement of the Si-rich polymer precursor enabled the more efficient and complete synthesis of Li 4 SiO 4 as a result of the accelerated covering and cleavage of Si–O–Si bonds on the Li 2 CO 3 particles at a much lower temperature. The present work suggests that the GSM strategy using combined ceramic and polymer precursors as proposed in this study is a promising alternative method to produce high quality Li 4 SiO 4 components with complex structures. • Our GSM strategy is extended to 3D printing using ceramic/polymer precursors. • Slurry formulation and printability, sinterability of parts and microstructures of sintered parts were characterized. • High material phase purity and strength for the skeleton were achieved with lower sintering temperature. • Improved strength by GSM enabled structure engineering with complete synthesis/rearrangement of material/microstructures.

Preparation of liquid polycarbosilane containing vinyl ether group and its rapid curing through thiol‐ene click reaction

AbstractIn this study, an SiC ceramic precursor vinyl ether–grafted liquid polycarbosilane (VE–LHBPCS) with approximate formulas of [SiH1.95(OCH2CH2OCH = CH2)0.05CH2]n was designed and synthesized. In order to cross‐link the ceramic precursor via fast thiol‐ene click reaction. The VE–LHBPCS was mixed with 1‐wt% ultraviolet (UV) decomposable free radical initiator BAPOs and 7‐wt% bis‐thiol compound 1,6‐hexanedithiol. According to Fourier transform infrared spectroscopy spectroscopy and photolithography experiment, more than 80% vinyl ether group was consumed within 3 s, and photolithography pattern with clear boundary could be formed after UV irradiation for only 1 s. Even for the VE–LHBPCS mixture with a thickness of 4 mm, 20‐s UV irradiation was sufficient to cure it with smooth surface and regular edge. Thermal gravimetric analysis demonstrated that the UV‐cured VE–LHBPCS mixture had a ceramic yield of 70.0 wt% at 1000°C, which was 20 wt% higher than that of raw LHBPCS. After pyrolysis up to 1000°C, about 29.5% isotropic linear shrinkage associated with the precursor‐to‐ceramic conversion was observed, and black dense ceramic with a density of 2.49 ± 0.09 g/cm3 and a chemical formula of SiC1.01O0.18S0.04 was obtained. With increasing the pyrolysis temperature, the content of element S decreased and the diffraction peaks of β‐SiC became sharper and stronger.

Synthesis of KBiFe2O5 by electrospinning: Structural, optical, and magnetic properties

Ferroelectric oxides are currently being studied as absorbing materials in photovoltaic devices due to their spontaneous polarization that facilitates charge separation. KBiFe2O5 (KBFO) is a ferroelectric oxide with a perovskite like structure that has a low band gap; however, it has a relatively low electrical conductivity, which makes it difficult to transport and collect carriers. One way of overcoming that deficiency would be by decreasing the dimensions of the active layer. Thus, in this work, for the first time, nanofibers of KBFO were produced by electrospinning. Aqueous solutions of the ceramic precursors in the form of Fe, K and Bi nitrates were electrospun using poly (vinylpyrrolidone) (PVP) as the carrier. The as-spun fibers were calcinated at different temperatures and times. The pure KBFO phase was obtained after calcination at 750 °C, during 1.5 h at 15 °C/min; the nanofibers had diameters between 300 nm and 800 nm as analyzed by scanning electron microscopy (SEM). The interplanar distances of the (100) and (111‾) planes were 0.78 and 0.37 nm, respectively, as calculated by a VESTA software, x-ray diffraction (XRD) and transmission electron microscopy (TEM). Using a Magnetization-Field (MxH) curve, KBFO was found to be highly paramagnetic with low magnetization. The band gap was measured by spectrophotometry via a Tauc plot, resulting in a value of 1.72 eV. Therefore, KBFO in the form of nanofibers seems to have a high potential as an absorbing material in photovoltaic cells.

Zirconia-alumina multiphase ceramic fibers with exceptional thermal stability by melt-spinning from solid ceramic precursor

Zirconia-alumina multiphase ceramic fibers with 80 wt% (Z80A20 fiber) and 10 wt% (Z10A90 fiber) proportions of zirconia were prepared via melt-spinning and calcination from solid ceramic precursors synthesized by controllable hydrolysis of metallorganics. The zirconia-alumina multiphase fibers had a diameter of about 10 µm and were evenly distributed with alumina and zirconia grains. The Z80A20 and Z10A90 ceramic fibers had the highest filament tensile strength of 1.78 GPa and 1.87 GPa, respectively, with a peak value of 2.62 GPa and 2.71 GPa. The Z80A20 ceramic fiber has superior thermal stability compared to the Z10A90 ceramic fiber and a higher rate of filament strength retention due to the stability in grain size. After heat treatment at 1100 °C, 1200 °C, and 1300 °C for 1 h respectively, the filament tensile strength retention rate of Z80A20 ceramic fibers was 87 %, 80 %, and 40 %. While Z10A90 ceramic fiber was fragile after being heated at 1300 °C. The results showed that the high zirconia content facilitated the fiber's thermal stability.

Fabrication and characterization of ZrC nano-ceramics derived from a single-source precursor and its feasibility as ZrC/C fibers in structure and function

A novel ZrC ceramic precursor was prepared by a polymer-derived ceramics method and ultraviolet (UV) crosslinking by using zirconium tetrachloride (ZrCl4), ethylenediamine (EDA), and diallylamine (DAA) as raw materials. On this basis, polyacrylonitrile (PAN)-based carbon nanofiber (CNF)-coated ZrC ceramic precursors were synthesized by electrostatic spinning. The as-prepared fibers exhibited excellent designability and machinability by adjusting the proportion of precursors. X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) revealed that these materials are converted to nano-sized ZrC ceramics and ZrC/C fibers with a highly crosslinked network structure after high-temperature annealing. ZrC/C fibers still maintained good electrochemical properties at high temperatures. Finally, the tensile test revealed that the mechanical properties of ZrC/C fibers are significantly superior to those of CNF. Specifically, the ceramic fibers with 25% ZrC content exhibited the maximum tensile strength of 71.7 MPa.

Key role of interphase in continuous fiber 3D printed ceramic matrix composites

During the continuous fiber (CF) 3D printing process, the high viscosity of the printing materials makes it difficult to penetrate into the fiber bundles, resulting in the lack of matrix and poor interfacial bonding. In this paper, the interfacial bonding of CF 3D printed ceramics was controlled by chemical vapor infiltration (CVI). A thermoplastic ceramic precursor and continuous carbon fibers were used as printing materials, and complex lightweight structures were printed. After cross-linking and pyrolysis, the ceramic precursor was converted into amorphous SiOC. Then CVI process was carried out to control the interphase and fill the fiber bundles with ceramic matrix. The flexural strength and modulus increased with the increase of CVI time. When the PyC interphase thickness was 150–250 nm, the flexural strength increased by about 203%. Each fiber was surrounded by the interphase and dense ceramic matrix, which was the reason for the improvement of mechanical properties.

Ceramic precursor-phthalonitrile hybrid with improved high heat resistance through constructing binary continuous phases

Achieving organic–inorganic hybrids with improved heat resistance above 500 °C using inorganic materials as filler remains a challenge because inorganic constitutes could not form continuous inorganic phases in hybrids. Here, we obtained organic–inorganic phthalonitrile hybrids with increased heat resistance using ceramic precursor (SiBCN) as the inorganic source. The results showed that hybrids formed Si-O bond between phthalonitrile and the ceramic precursors. The carbon fiber reinforced composites of hybrids exhibited high glass transition temperatures (over 700 °C). The hybrid with 30 wt% SiBCN displayed a high temperature for losing 10 % weight (above 555.4 °C (N2)), and high mass residue (over 75 % at 900 °C (N2)). The improved heat resistance of the hybrid was originated from the continuous inorganic phases derived from the ceramic precursors delaying transfer and escape for the small molecules generated in the phthalonitrile resin at elevated temperature. Furthermore, the hybrid showed excellent high-temperature stability of thermal conductivity. The as prepared organic–inorganic hybrids could potentially replace ceramic-based materials in servicing temperatures ranging from 500−700 °C.

Preparation of self-healing Cf/SiBCN(O) composite using a novel polyborosilazane

In this study, novel polyborosilazane-derived SiBCN(O) ceramic was used as self-healing component in self-healing Cf/SiBCN(O) composite, which was prepared by polymer infiltration and pyrolysis (PIP) process. Molecular-level structure design of boron-containing ceramic precursors was utilized to achieve uniform dispersion of boron-containing self-healing components in prepared composites. No elemental diffusion was observed at the interface of ceramic matrix and carbon fibers, which resulted in stable SiBCN(O) structure. In addition, boron was uniformly distributed in Cf/SiBCN(O) composite ceramic matrix, which was beneficial for self-healing of cracks. Cracks and indentations were able to heal at high temperatures in air. The best crack-healing behavior occurred in air atmosphere at 1000 °C, with nearly complete crack healing. This excellent self-healing behavior was achieved because silicon and boron atoms in SiBCN(O) ceramic reacted with available oxygen at high temperatures to form SiO2(l), B2O3(l), and B2O3·xSiO2 liquid phases, which effectively filled cracks. In general, as-prepared Cf/SiBCN(O) composite exhibited excellent self-healing properties and shows great application potential in high-temperature environment applications such as aviation, aerospace, and nuclear power.

Material extrusion for ceramic additive manufacturing with polymer-free ceramic precursor binder

Additive manufacturing of dense ceramic products has been challenging because of the high polymeric content of the ceramic feedstock materials. Several studies have been conducted to increase the ceramic content in the feedstock, but the binder and additives in it have remained in the polymeric content. A novel strategy for highly dense additive manufacturing using a sol-gel-based ceramic slurry without polymeric additives is presented. Alumina, which is the most widely used fine ceramic, was chosen as a representative ceramic material. The proposed sol-gel solution enabled a high solid loading of approximately 50 vol% without any polymeric dispersant while satisfying the requirements for material extrusion process, such as extrudable viscosity (<100 Pa.s) and self-sustainable yield stress. This novel sol-gel binder system evolves into aluminum oxide nanoparticles during the sintering process, eventually fusing to the alumina particles. The as-printed green body possessed high alumina content and 66% of theoretical density, which was higher than that obtained via the conventional molding methods. A reduced linear shrinkage of less than 16% and a high density of 99.5% of the theoretical value were also achieved. This research would present a practical strategy for ceramic additive manufacturing as an emerging fabrication process.

Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) as a potential on site tool to test geopolymerization reaction

Geopolymers, synthesized starting from aluminosilicate precursors activated with alkaline solutions, constitute a class of materials of high interest as potential substitutes of traditional, cementitious, binders. Infrared spectroscopy is one of the routine analytical techniques employed to study these materials and to verify the occurrence of geopolymerization; on the other hand, its portable version working in diffuse reflection is not enough exploited for their characterization. The aim of this work is therefore to assess the potentiality of Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) in the study of geopolymers. The combination of this technique with Principal Components Analysis (PCA) statistical treatment was used to search for criteria able to discriminate the successful products from those which require a correction in their formulation.Mainly, two groups of geopolymers were studied, based respectively on clay sediments and ceramic waste precursors, in the latter case with the possible addition of metakaolin. These samples were studied both after maturation, comprising several variables in their mix-design and curing, and during the first hours of solidification of the slurry. The results allowed to identify the best formulations within the analyzed groups. Besides, the extension of this study to a wider selection of geopolymers, such as the pumice-, volcanic paleo-soil- and/or metakaolin-based ones, already studied with other techniques, further confirmed the efficacy of DRIFT spectroscopy in the identification of the geopolymerization reaction.

Polysilazane-derived SiCN ceramics-based layerless printing

In the process of light curing printing, layer steps are formed in the stacking direction. As these steps, i.e., by-products, affect the accuracy and quality of the printed surface significantly, avoiding their formation during printing is a prominent research topic. In this study, we propose a layerless printing method.Layerless printing uses the inhibition effect of oxygen on the polymerization reaction of ceramic precursor photosensitive resins, construct the oxygen inhibition layer during the printing process. We control the oxygen inhibition layer to weaken/eliminate the steps. In layerless printing, the high viscosity ceramic precursor photosensitive resin reduces the viscosity by heating up to make the fluidity of the material meet the printing conditions.The ceramic material can be realized straight-walled layerless in the z direction with a traditional layer thickness (100 µm). Furthermore, after pyrolysis of the printed ceramic precursor structure,the ceramic structure continued to retain zero layer steps.The result is that layerless printing reduced the surface roughness of the ceramic by 86.4%, the hardness and modulus of the ceramic were increased by approximately 10%, and the ceramic lattice of layerless printing was more uniformly stressed when subjected to compression stress. • Layer steps are eliminated by layerless printing. • The use of layerless printing can obtain a ceramic structure with a more uniform force. • Layerless printing can improve the accuracy of the print structure.