Sintering Time Research Articles

Fine-tuning the microstructure for improved performance in cold-sintered Li1.3Al0.3Ti1.7(PO4)3 composite solid electrolytes

Solid-state electrolytes (SSE) are one of the fundamental components of the upcoming generation of batteries since they increase the operational safety and efficiency. In this work, composite solid electrolytes (CSE) based on Li1.3Al0.3Ti1.7(PO4)3 and a (PEO2-LiTFSI) polymer matrix are obtained via the pioneering Cold Sintering Process (CSP), with a drastic reduction of the conventional sintering temperature. The CSP is performed at only 150 °C and 700 MPa, for 90 min of sintering time, by using a 3m acetic acid solution as the transient liquid phase (TLP). Here, the effect of the LATP particle size (d50) is studied to tailor the final microstructure, which enables the fine-tuning of the ultimate electrical properties of the electrolyte. An optimum d50 of 0.415 μm produces CSEs with 91 % of relative density, an ionic conductivity of 0.169 mS/cm, activation energy of 0.293 eV and electrical stability under 0.1 mA/cm2, thus leading to competitive properties.

Slag after Smelting of Anode Mud: Role of Sulphiding Sintering

The study object was slag from the Balkhash copper smelter, obtained by re-melting anode mud containing nonferrous metals. The process flow for processing these slags includes sintering with Na2SO4, Na2CO3, and coal, followed by soda-alkaline leaching of the sinter and extraction of metals from the solution into marketable products. Since sintering is the main operation providing high selectivity, the composition of the products of this process was studied. The main transformations during sintering were determined, and the optimal parameters were identified. The structures of slags and sintered materials obtained during the experiments were studied by electron-probe microanalysis. Sintering was performed at 600–800 °C. The best results for sulphidization of slag components were obtained at 800 °C; a further increase in temperature leads to the smelting of sinter particles and slows down sulphidization. The optimal quantities of additives, based on the weight of the slag, are Na2SO4—45%, Na2CO3—15%, and reducing agent—41%, with a sintering time of 2 h. These conditions enable the sulphidization of non-ferrous metals in the slag to the entire depth of the polymetallic globules. The distinct concentration of harmful impurities (Ni, As, and Sb) was observed in the fine structure of the polymetallic globules.

Integrating High-Performance Flexible Wires with Strain Sensors for Wearable Human Motion Detection.

Flexible electronics have revolutionized the field by overcoming the rigid limitations of traditional devices, offering superior flexibility and adaptability. Conductive ink performance is crucial, directly impacting the stability of flexible electronics. While metal filler-based inks exhibit excellent conductivity, they often lack mechanical stability. To address this challenge, we present a novel conductive ink utilizing a ternary composite filler system: liquid metal and two micron-sized silver morphologies (particles and flakes). We systematically investigated the influence of filler type, mass ratio, and sintering process parameters on the composite ink's conductivity and mechanical stability. Our results demonstrate that flexible wires fabricated with the liquid metal/micron silver particle/micron silver flake composite filler exhibit remarkable conductivity and exceptional bending stability. Interestingly, increasing the liquid metal content results in a trade-off, compromising conductivity while enhancing mechanical performance. After enduring 5000 bending cycles, the resistance change in wires formulated with a 4:1 mass ratio of micron silver particles to flakes is only half that of wires with a 1:1 ratio. This study further investigates the mechanism governing resistance variations during flexible wire bending. Additionally, we observed a positive correlation between sintering temperature and pressure with the conductivity of flexible wires. The significance of the sintering parameters on conductivity follows a descending order: sintering temperature, sintering pressure, and sintering time. Finally, we demonstrate the practical application of this technology by integrating the composite ink-based flexible wires with conductive polymer-based strain sensors. This combination successfully achieved the detection of human movements, including finger and wrist bending.

Microwave‐sintered mullite structural ceramics based on low‐grade bauxite applied for fracturing proppants

AbstractThis study aimed to assess the feasibility of manufacturing fracturing proppants by microwave sintering and using low‐grade bauxite as raw material. The effects of microwave hotspot SiC and sintering additive MnO2 content on the performance of the mullite‐based structural materials were studied, respectively. The optimum sintering condition was determined by single‐factor experiments. The sintering process and mechanism were explored based on the analysis of physicochemical properties, phase transitions, and microstructure. The results showed that (1) mullite ceramic composites could be successfully prepared only with SiC added and with poor interparticle bonding microstructure. (2) With the addition of MnO2 and CaO, the granular‐shaped mullite crystals transformed into rod‐like mullite crystals, forming a net structure. (3) As the input power increased, the overfast sintering rate would reduce proppants' mechanical properties, and it was also necessary to select a reasonable sintering time to avoid overburning. (4) When the mass ratio of MnO2:CaO:SiC:bauxite was 2:1.5:12:84.5 and under the sintering condition of 1000 W, 2 h, the performance (breakage ratio of 8.5% under 28 MPa closed pressure, apparent density of 2.58 g/cm3, turbidity of 52 FTU, and acid solubility of 6.77%) could meet the requirements of the Chinese Petroleum and Gas Industry Standard (SY/T 5108–2014). This study provides a powerful way for reducing the fracturing cost, which not only improves the low‐grade bauxite utilization scale within the ceramic industry, but also expands the application of microwave sintering technology in mullite structural materials for the petroleum and gas industry.

Technology verification of Portland cement clinker production driven by concentrated solar energy directly

Fuel substitution is an important measure for heat substitution and carbon emissions reduction in cement production by using low-carbon fuels such as solid waste, natural gas, biomass energy and solar energy. In this study, a technology that uses concentrated solar energy to directly drive solar cement clinker production is proposed and its feasibility is experimental demonstrated. The results showed that cement clinker could be burned using concentrated solar energy. Because the sintering rate is rapid, rapid burning and/or under-burning also occurs during the sintering process, which causes the clinker structure exhibit a sheet structure. The chemical composition analysis showed that the total mass fraction of dicalcium silicate (C2S) and tricalcium silicate (C3S) exceeded 70 %, the mass fraction of f-CaO was higher than the standard value (≤1.5 %). Controlling the sintering temperature and time, and increasing the cooling rate are significant factors in ensuring the quality of the cement clinker.

Rapid preparation of Si3N4 ceramics with high thermal conductivity and low dielectric loss by fast hot-pressing (FHP) sintering

A series of Si3N4 ceramics with MgO and Y2O3 as sintering additives were successfully prepared by fast hot-pressing (FHP) sintering at the sintering temperature of 1700 °C, with the hold time of only 10 min and the whole sintering process of 36 min. The sintering behavior, densification process, microstructure, crystalline phase composition, bond composition, thermal conductivity and dielectric properties were systematically investigated. FHP reduces the sintering temperature and sintering time of Si3N4 ceramic compared to traditional solid-state method. The results of a series of tests have shown that the densification of Si3N4 ceramics and the phase transition from α-Si3N4 to β-Si3N4 can be facilitated by appropriate levels of additives, resulting in a dense, homogeneous and non-porous microstructure. Additionally, based on test results in this work, Si3N4 -4 wt.% Y2O3 -2 wt.% MgO exhibit the highest thermal conductivity of 78.16 W/mK, the dielectric constant of 8.50 and the dielectric loss of 5.52 × 10−4. The Si3N4 ceramics investigated in this work exhibit excellent properties for use of power semiconductor device packages, microwave devices, and power electronics. And also demonstrate the potential of FHP in laying the foundation for the further preparation of higher performance Si3N4 ceramics.

Structure and property evolution of LaYbZr2O7/YSZ heterogeneous interface in double‐layer thermal barrier coatings after thermal exposure

AbstractDouble‐layer thermal barrier coatings are one of the development directions of thermal barrier coatings technology. LaYbZr2O7 (LYZO) has high toughness and low thermal conductivity, making it promising for use as a high‐temperature thermal barrier coating. However, its relatively poor mechanical properties, especially low fracture toughness, limit its further application. Therefore, we prepared a double‐layer coating of LYZO and Y2O3 partially stabilized ZrO2 (YSZ) using atmospheric plasma spraying, with the inner layer being YSZ and the outer layer being LYZO. The results showed that after spraying, LYZO was in the metastable fluorite phase, while YSZ was in the tetragonal phase. LYZO and YSZ had good chemical compatibility, and an interaction layer formed at the interface between them, with its thickness increasing with the sintering time. Eventually, after 100 h of heat treatment, the thickness reached 12 µm. The hardness of the LYZO/YSZ interface increased with the sintering time, reaching a maximum value after sintering at 1300°C for 10 h. When evaluating the interfacial bonding strength using indentation method, the length of cracks caused by indentation significantly decreased with the increase of sintering time. The increase in bonding strength can be attributed to the formation of a reaction layer and the reduction of thermal residual stresses. Raman spectroscopy was used to measure the thermal residual strain at the LYZO/YSZ interface. Unbalanced distribution of thermal residual stress and M phase was observed near the interface. As the sintering time increased, both thermal residual stress and M phase content decreased. In summary, the double‐layer thermal barrier coating of LYZO/YSZ has good potential for development.

A novel manufacturing process for intermetallic thin-walled components: Forming and hot pressing of thin-walled laminates prepared by laying/winding metal foil strips

To address the challenge of manufacturing NiAl intermetallic thin-walled components, an integrated manufacturing process using the preform prepared by laying/winding of metal foil strips was proposed. This method entails the initial fabrication of a stacked foil preform via the laying/winding of metal foil strips, followed by pre-sintering to prepare a laminated preform. Subsequently, precise shaping is achieved through hot bulging of the laminated preform, while the NiAl intermetallic phase is obtained through reaction synthesis of Ni and Al foils under hot pressing. The microstructure of Ni/Al/Ni laminated preforms under varied sintering parameters and different laminating methods were analyzed. Additionally, the deformation behaviors of these preforms at both room and high temperatures were investigated via tensile tests and bulge tests. Results show: (1) The micro-cracks and Ni-Ni interface delamination occurred in the brittle Ni2Al3 layer of the laminated preform. The deformation capability of laminated plates decreased as the thickness of the brittle Ni2Al3 layer increased with sintering time. (2) Tiny gaps between foils due to laying path and foil size deviations, causing reduced deformability and fractures when the tensile direction was perpendicular to these gaps. (3) These gaps and micro-cracks can be progressively eliminated through hot pressing sintering processes. The findings verify the preliminary feasibility of the proposed novel manufacturing process and provide a novel solution for manufacturing NiAl intermetallic thin-walled components.

Evolution of electrical resistance of graphite foils during spark plasma sintering

The progression of the electrical resistance of graphite foils during spark plasma sintering process (SPS) was investigated at constant temperature and pressure. The study applied various set-ups of the SPS device, and the electrical data used for the evaluation of electrical resistance (heating power and current) was obtained from the SPS apparatus in real-time. The contact resistance and resistance due to graphite foil/s was evaluated by subtracting the resistance of the single punch set-up from the set-up of two punches in direct contact and the set-ups with various graphite foils. The results showed that during the initial stages of sintering, set-up resistance increases with time and that, overall, set-up resistance increases with number of graphite foils. Both contact resistance and resistance due to graphite foils was found to decrease with sintering time. In contrast to previous conceptions, the electrical resistance of graphite foils changes in response to sintering conditions during the SPS process.

Predicting hardness of graphene-added Si3N4 using machine learning: A data-driven approach

This study presents a data-driven framework based on machine learning (ML) using extreme gradient boosting (XGBoost) for predicting the hardness of silicon nitride (Si3N4) ceramics reinforced with graphene. The XGBoost model takes into account various factors such as graphene type and content, characteristics of the raw Si3N4 powder, the parameters of the sintering process (sintering technique, temperature, pressure, holding time), and the characteristics of the sintered samples, i.e., the density, αβ content and Vickers hardness. The parameters that influence the Si3N4 hardness most strongly are identified, with sintering pressure, sintering time and density being the most influential. The addition of graphene content up to a certain threshold (1 wt%) has a positive impact on hardness. However, beyond that it leads to a lower density and a lower mechanical performance. Sintering parameters, particularly the sintering pressure, temperature, holding time and technique, strongly affect the density, final grain size, αβ Si3N4 composition and subsequently the hardness. The study highlights the importance of density and the densification process in achieving high hardness in Si3N4 ceramics. The developed ML model provides a valuable tool for predicting the hardness of Si3N4+graphene ceramics composites and offers insights into selecting suitable graphene type, content, and processing parameters. While the study primarily focuses on Si3N4+graphene composites, this novel approach holds promise for the in-silico design and analysis of diverse ceramic materials.

Microwave sintering of CaBi2Nb2O9 ceramics for improved piezoelectric response and electrical resistivity

AbstractCaBi2Nb2O9 (CBN) ceramic is a promising sensing element to convert vibration to electrical signal at temperatures higher than 600°C. However, conventionally sintered ceramics suffer from poor piezoelectric coefficient (d33) and low electrical resistivity (ρdc). Here, we report that CBN ceramics can be prepared by microwave sintering (MS) to mitigate volatilization issue of Bi2O3 and thus suppress the generation of oxygen vacancies usually seen in conventional sintering (CS) as demonstrated by X‐ray photoelectron spectroscopy (XPS) analysis and mass‐loss measurement. As compared to the CS, the MS is more favorable for reducing the sintering time, and obtaining a dense, fine, and uniform grain morphology as revealed by scanning electron microscopy (SEM) characterizations of both surface and interior of the CBN ceramics, leading to an enhancement of 86% and 75% in d33 and ρdc, respectively. Piezoresponse force microscopy (PFM) as combined with Rayleigh law analysis clearly revealed that the enhancement of piezoelectric properties was attributed to the thinner domains, the higher domain wall density, and the enhanced domain wall motion in the MS‐940 samples. This study paves an important road to simultaneously improve both d33 and ρdc in CBN ceramics for developing high‐temperature vibration sensors.

Multi-objective parametric optimization process of hybrid reinforced titanium metal matrix composite through Taguchi-Grey relation analysis (TGRA)

Hybrid titanium metal matrix composites (HTMMCs) are advanced composite materials that can be tailored to a variety of applications. Because of their decreased fuel consumption and cost, they are popular in the transportation industry. Using multi-objective optimization and Taguchi-based Grey relational analysis (TGRA), this study investigates the impact of hybrid reinforced HTMMCs synthesized using powder metallurgy on their physic mechanical properties. The research investigates reinforcements such as B4C, SiC, ZrO2, and MoS2 at various compaction pressures, milling durations, and sintering temperatures. The best powder metallurgy control parameters for HTMMC synthesis, with a milling time of 5 h, a compaction pressure of 40 MPa, a sintering temperature of 1200 °C, and a sintering time of 1 h, and a compaction time of 40 min. According to validation results, HTMMC material with optimized process parameters had experimental densities, porosities, hardness, compressive strength, and wear rates of 4.29 gm/cm3, 0.1178%, 71.53RHN, 2782.36 MPa, and 0.1519 mm3 correspondingly. The material hardness was increased by 1.99% and compressive strength by 2.87%. The use of Taguchi and GRA techniques strongly verified that the impact of milling duration and sintering temperature was the greatest of all five factors. The novel synthesized hybrid reinforcing HTMMCs outperformed pure Ti grade 5 and single and double fortified HTMMCs in terms of physic mechanical characteristics. As a result, the newly developed tetra hybrid reinforced HTMMC material is expected to be used in heavy-duty vehicles, aerospace, automobiles, maritime, and other industries.

Hyperdoping: doping TiO2 beyond thermodynamic limits using Flash sintering

For the first time, it has been demonstrated that TiO2 optical properties can be improved by doping Fe using flash sintering. Hyperdoped TiO2 (doped with 10 at% Fe) fabricated using flash sintering, exhibited remarkable improvements in optical characteristics. Hyperdoping (exceeding the equilibrium solubility limit), induces charge trap centers or inhibits charge recombination in semiconductors. By employing XPS and UV-Vis spectroscopy, surface species alterations including oxygen vacancies, Ti4+, Ti3+, and optical characteristics were investigated. With varying holding periods, flash sintering unveiled substantial enhancements in optical absorbance and absorption regions by generating Ti3+ and oxygen vacancies. Notably, a 10-second hold time during flash sintering displayed the highest redshift among the investigated samples, indicating superior optical improvement. Oxygen vacancies and Ti3+ increased with decreased holding time during flash, suggesting the influence of flash sintering parameters on forming a metastable phase, signifying the pivotal role of flash sintering's time parameter in modulating material properties.

Effect of binder content and sintering time on the microstructure and mechanical properties of gradient cemented carbides with Ni binder

Replacement of Co by alternative Ni binder in gradient cemented carbide is an effective way to reduce the health concerns associated with Co powders. In the present work, gradient cemented carbides with different Ni contents and gradient sintering times were prepared by traditional powder metallurgy with a two-step sintering method. The microstructure of cemented carbide including the gradient layer formation was analyzed by XRD, SEM, EDS, TEM, and EBSD. The thickness of the gradient layer is almost proportional to the square root of sintering time, indicating that the gradient layer formation is a diffusion-controlled process. The atomic migration can be accelerated to form a thicker gradient layer with the increase of the binder content. The coherent interface of the Ti(C, N) core-rim structure for the gradient cemented carbides with Ni binder was revealed. With the increase in binder content, the average grain size of the WC phase is increased. The hardness and fracture toughness of the cemented carbides were also studied and analyzed according to the crack propagation behavior and the distribution of dislocation and stress indicated by KAM and GND. The variation of the hardness and the fracture toughness with the sintering time is mainly related to the density and the grain size of hard phases, while the change of the mechanical properties along with the Ni content probably results from the local dislocation density and the stress in the cemented carbides. The cemented carbide can obtain a good combination of hardness and fracture toughness with 10 wt% Ni gradient sintered for 2h.

Microstructure, mechanical and corrosion property of neutron and γ-ray shielding (Gd2O3+W)/Al composites

In this study, a neutron and γ-ray absorbing (Gd2O3+W)/Al composite was fabricated by vacuum sintering. Firstly, through Monte Carlo Neutron and Photo Transport Code (MCNP) calculations, the content of Gd2O3 and W in the composite was determined to be 10 wt% and 25 wt%, respectively. Then, the influence of sintering temperature and sintering time on the microstructure, density, compression properties and electrochemical corrosion behavior of the (Gd2O3+W)/Al composites were investigated. The results indicate that sintering temperatures below 600 °C and sintering times shorter than 2 h led to insufficient density of the composite. Conversely, sintering temperatures above 600 °C and sintering times longer than 2 h caused W to agglomerate, resulting in a decrease in the density of the composite and a deterioration of its electrochemical performance. Therefore, the optimal sintering temperature and sintering time for the (Gd2O3+W)/Al composites were determined to be 600 °C and 2 h, respectively. Finally, the immersion corrosion performance in H3BO3 solution of the composite fabricated by the optimal process parameters was studied in detail. It was found that pitting was the main corrosion form of the (Gd2O3+W)/Al composite, and an oxidation film mainly composed of Al2O3 was formed on the surface.

Simple and solvent-free procedure for fabricating Ag/Bi-based halide double perovskite polycrystalline wafers and investigating their photodetector properties

Herein, a solvent-free and simple solid-state method was used to synthesize Cs2AgBiBr6 wafers. Cs2AgBiBr6 particles were successfully synthesized in two steps, namely grinding and annealing. Phase-pure Cs2AgBiBr6 was produced in a very short time, such as 4 h, by stepwise heat treatment at 205 °C for 2 h and 250 °C for 2 h after grinding bromide powders for 20 min in an agate mortar. Another grinding step for 20 min, following the phase-pure synthesis of Cs2AgBiBr6, facilitated the formation of larger perovskite grains through sintering at 350 °C. Increasing the sintering time from 4 h to 20 h also contributed to the formation of larger and more compact perovskite grains. This study demonstrated that the formation of larger and more compact grains through sintering at 350 °C for 20 h contributes to better detectivity and responsivity values for solvent-free produced Cs2AgBiBr6 wafers. Additionally, the structural strength of the material was examined through hardness tests using the nanoindentation method, resulting in a value of 0.0923 MPa. The simple and solvent-free method employed in this study may create opportunities to fabricate emerging double perovskites for detector applications.

Color Characteristics of High Yttrium Oxide–Doped Monochrome and Multilayer Partially Stabilized Zirconia upon Different Sintering Parameters

Abstract Objectives Sintering influences the optical properties of zirconia. This study examined the effect of altering sintering temperature and time of monochrome (Mo) and multilayer (Mu) 5 mol% yttria-partially stabilized zirconia (5Y-PSZ) on color characteristics. Materials and Methods Three hundred specimens (width × length × thickness = 10 × 20 × 2 mm) were prepared from Mo and Mu (with cervical [C], middle [M], and incisal [I] region) 5Y-PSZ and randomly sintered at decreasing (Td: 1,450°C), regular (Tr: 1,500°C), and increasing (TI: 1,550°C) sintering temperature, with extremely short (He: 10 minutes), ultrashort (Hu: 15 minutes), short (Hs: 30 minutes), and regular (Hr: 135 minutes) sintering time (n = 15/group). Color appearance (EW ), translucency parameter (TP), contrast ratio (CR), opalescence parameter (OP), and color appearance difference (∆E diff) were evaluated in the CIE L*a*b* system. Microstructures were evaluated by scanning electron microscope (SEM) and X-ray diffractometer (XRD). Statistical Analysis Analysis of variance (ANOVA) and Bonferroni comparisons were determined for significant differences (p < 0.05). Results Significant differences in color parameters upon zirconia type, sintering temperature, and sintering time, and their interactions were indicated (p < 0.05). Increasing sintering temperature and extended sintered time resulted in larger grain, reduced tetragonal-to-monoclinic phase transformation, and significantly increased the TP and OP, but decreased the CR and ∆E diff (p < 0.05). Decreasing sintering temperature and time led to clinically unacceptable color appearance. Conclusion Mo was found to be more translucent than Mu. To achieve the most favorable optical properties, increasing sintering temperature and extending sintering time are recommended. Decreasing sintering temperature is not suggested. However, shortened sintering time is feasible, but it needs sintering with increasing sintering temperature to achieve a promising color appearance.

Low-temperature sintering of ceramic bricks from clay, waste glass and sand

In the present work, bricks were made on a real 1:1 scale for the construction of housing. For the preparation of the mixtures, raw materials such as clay, sand and glass obtained from the recycling of brown beer containers were used, applying the method plastic molding for the preparation of the semi-products. It has been established that the addition of sand containing a small amount of montmorillonite to such clay enabled to realization of plastic molding. The incorporation of glass into the clay provided to substantially reduce the sintering time of the bricks up to 8h and to vary their strength properties. Sintering was carried out at 800°C in an air atmosphere. The results of X-ray diffraction (XRD), X-ray fluorescence (XRF) and field emission scanning electron microscopy (FESEM) and EDS microanalysis have shown that the raw materials and ceramic bricks contains quartz and feldspars. Low-temperature sintering has made it possible to obtain high-quality, high-strength building bricks in accordance with standards.

Microstructure and finite element analysis of Mo2C-diamond/Cu composites by spark plasma sintering

Abstract Mo2C layer was generated on the diamond surface via vacuum micro-evaporating, which was used as the reinforcement particles to fabricate diamond/Cu composites by spark plasma sintering (SPS). The effect of evaporation parameters on the forming of Mo2C, and the holding time on diamond/Cu composites fabrication is studied. Combined with the experiment and finite element analysis (FEA), the holding time on diamond/Cu composites influence on the thermal conductivity (TC) of composites is further discussed. The results show that the Mo2C area on the diamond surface would gradually enlarge and cover the diamond surface evenly with the increment in evaporation time and temperature, better vacuum micro-evaporating parameters were given as 1,000°C for 60 min. The fractures in the diamond/Cu composites are mainly ductile fractures on copper and diamond falling out from the Mo2C interface. It was found that sintering time would significantly influence the dissipation property of diamond/Cu composites. A comprehensive parameter for SPS was obtained at 900°C, 80 MPa for 10 min, the relative density (RD) and TC of the composites obtained under the parameter were 96.13% and 511 W/(m K). A longer sintering time would damage the Mo2C interlayer and further decrease the bonding between copper matrix and diamond particles, which would lower the RD and TC of composites. It can be obtained from the comparison of simulation results and experimental results that the FEA result is closer to the experimental results due to the gaps with low heat conduction, and the air in the gaps is added in the simulation process.

Preparation of Y2Si2O7 fibrous porous ceramics and its ablation behavior with different heat fluxes

Fibrous porous ceramics have been receiving more and more applications in the thermal protection field of vehicles. In this study, we prepared Y2Si2O7 fibrous porous ceramics (YFPCs) from Y2Si2O7 fibrous membranes via the molding method. The influence of sintering time and binder concentration on the properties of YFPCs was studied, and the oxyacetylene ablation behavior with different heat fluxes was also investigated. The results showed that YFPCs obtained at 2 h sintering time had a stable component composition and constant mechanical strength. YFPCs prepared at 40 wt% binder concentration had the maximum density and compressive strength, 0.47 g/cm3 and 0.68 MPa, respectively. The as-prepared ceramics exhibited favorable ablation resistance after oxyacetylene ablation for 120 s. The minimum linear ablation rate was 2.02 μm/s when the ablated surface temperature reached 1390 °C. When the surface temperature increased to 1872 °C and 2200 °C, the fibers on the ablated surface began to melt, and the linear ablation rate increased to 9.63 μm/s and 77.63 μm/s, respectively.