Mullite Phase Research Articles

Sugarcane Bagasse ash substituent feldspar for the production of porcelain electrical insulators

Sugarcane bagasse ash (SCBA) industrial waste was used to partially substitute feldspar in the production of porcelain electrical insulators from a mixture of locally available Bombawuha clay (BC), Chancho sand (CS), and mixture of Wolkite (WF) and Arerti feldspar (AF) (50:50%). The raw materials were characterized for their chemical composition, mineralogy, thermal behavior, and plasticity. The porcelain electrical insulator formulations containing various proportions of SCBA (0 wt%, 10 wt%, 15 wt%, and 20 wt%) were fired at different firing temperatures of 1200 °C, 1250 °C, and 1300 °C for 2.5 h. The fired bodies were evaluated for water absorption, apparent porosity, bulk density, flexural strength, dielectric strength, and microstructure. The results showed that SCBA had 65.06% silica (SiO2) and had higher alkaline and iron oxide (Fe2O3) contents than the natural feldspars. Bombawuha clay contained kaolinite as a major mineral with a middle range plasticity index (PI = 11.2%) and the met the required purity necessary for mullite phase formation. The feldspars had a low alkali content of sodium oxide plus potassium oxide (Na2O + K2O) of < 6 wt %. The prepared porcelain insulator containing 10% SCBA, 50% BC, 30% mixed feldspars, and 10% CS, and fired at 1250 °C for 2.5 h exhibited a water absorption of 0.35%, flexural strength of 42.50 MPa, and a dielectric strength of 6.59 kV/mm, which satisfies the obligatory properties for quality porcelain insulators. Further, the partial replacement of feldspar by SCBA up to 10 w% lowered the firing temperature by 50 °C.

Preparation of high-performance silica-based ceramic cores with B4C addition using selective laser sintering and SiO2–Al2O3 sol infiltration

Silica-based ceramic cores are commonly employed to fabricate hollow aero-engine blades during investment casting. However, achieving excellent performance and high precision remains an extremely challenging problem. In this study, silica-based ceramic cores with boron carbide (B4C) addition were prepared by selective laser sintering (SLS) and SiO2–Al2O3 sol infiltration. The effects of B4C content and mass ratio of alumina to silica in the SiO2–Al2O3 sol on the mechanical properties of the obtained silica-based ceramic cores were explored. The results suggested that the room temperature flexural strength was gradually improved from 3.39 MPa to 27.35 MPa at B4C content from 0 to 2 wt% due to the oxidation of B4C, and the linear shrinkage gradually increased to 4.61%. Furthermore, the high temperature flexural strength was enhanced from 4.86 MPa (non-infiltrated) to 11.84 MPa at mass ratio from 0 to 1 because of the generated mullite phase and the linear shrinkage decreased to 1.38%, which can meet the application requirements for the preparation of ceramic cores. Consequently, it shows the capability to prepare high-performance silica-based ceramic cores with B4C addition by combining SLS technology and SiO2–Al2O3 sol infiltration process.

3D spiny AlF3/Mullite heterostructure nanofiber as solid-state polymer electrolyte fillers with enhanced ionic conductivity and improved interfacial compatibility

Lithium metal batteries assembled with solid-state electrolyte can offer high safety and volumetric energy density compared to liquid electrolyte. The polymer solid-state electrolytes of poly(ethylene oxide) (PEO) are widely used in lithium metal solid-state batteries due to their unique properties. However, there are still some defects such as low ionic conductivity at room temperature and weak inhibition of lithium dendrite growth. Herein, the spiny inorganic nanofibers heterostructure with mullite whiskers grown on the surface of aluminum fluoride (AlF3) nanofibers are introduced into the PEO-LiTFSI electrolytes for the first time to prepare composite solid-state electrolytes. The AlF3 as a strong Lewis acid can adsorb anions and promote the dissociation of Li salts. Besides, the specially three-dimensional (3D) structure enlarges the effective contacting interface with the PEO polymer, which allows the lithium ions to be transported not only along the large aspect ratio of AlF3 nanofibers, but also along the mullite phase in the transmembrane direction rapidly. Thereby, the transport channel of lithium ions at the spiny inorganic nanofibers-polymer interface is further improved. Benefiting from these advantages, the obtained composite solid-state electrolyte has a high ionic conductivity of 1.58 × 10−4 S cm−1 at 30 °C and the lithium ions transfer number of 0.53. In addition, the AlF3 has strong binding energy with anions, low electronic conductivity and wide electrochemical stability window, and reduced nucleation overpotential of lithium during cycling, which is positive for lithium dendrite suppression in solid-state electrolytes. Thus, the assembled symmetric Li/Li symmetric batteries exhibit stable cycling performance at different area capacities of 0.15, 0.2, 0.3 and 0.4 mA h cm−2. More importantly, the LiFePO4 (LFP)/Li battery still has 113.5 mA h g−1 remaining after 400 cycles at 50 °C and the Coulomb efficiency is nearly 100% during the long cycle. Overall, the interconnected structure of 3D spiny inorganic heterostructure nanofiber constitutes fast and uninterrupted lithium ions transport channels, maximizing the synergistic effect of interfacial transport of inorganic fillers and reducing PEO crystallinity, thus providing a novel approach to high performance solid-state electrolytes.

Effect of Al(OH)3 addition on densification mechanism and properties of reaction-sintered mullite-corundum composite ceramics

ABSTRACT Mullite composite ceramics were fabricated by using mullite powder from waste coal gangue and Al(OH)3 as starting materials. The effects of sintering temperature and Al(OH)3 content on phase composition, microstructure, and mechanical properties of the ceramics were systematically investigated. Results show that the bulk density and flexural strength of composite ceramics increase as the temperature increases from 1480°C to 1560°C. The composite ceramics exhibit optimal performances with addition of 10 wt.% Al(OH)3 at 1560°C, a bulk density of 2.43 g/cm3 and a flexural strength of 124.28 MPa, respectively. Moreover, additional Al(OH)3 promotes a reaction between SiO2 and Al2O3 and forms more mullite phase. The increase in mullite content endows the composite ceramics with high mechanical properties. Scanning electron microscope images indicate that the mullite particles exhibit an interlocking structure, while the corundum phase is “pinned” within the mullite interlocking structure, contributing to the mechanical properties of composite ceramics.

Optimized synthesis of mullite ceramics in thermal plasma

Mullite has low thermal expansion coefficient, thermal conductivity and excellentresistance to thermal shock, and plays therefore an important role in the synthesis of modern ceramic materials. The paper presents the experimental results of mullite ceramics synthesis using thermal plasma. The ceramic samples are obtained from natural raw materials such as boehmite and silica sand in the stoichiometric Al2O3/SiO2 ratio of 1.86, 3 and 5.67. It is shown that the optimal operation mode of the arc plasma torch in the synthesis of mullite-containing samples from an 8 g charge weighing includes 80 A current, 100 V voltage, and 60 s exposure time. With such technological parameters, the melting product is a hemisphere with diameter 23 mm and thickness 11 mm, which indicates to a complete transition of the initial components to the molten state. The synthesized ceramic samples are characterized by the crystalline phase of mullite 3Al2O3 ·2SiO2. At the same time, at the Al2O3/SiO2 ratio of 1.86, cryptocrystalline diffraction maxima are observed at 2θ = 53–54° and 69–76° due to the increased content of SiO 2 . According to morphological studies performed for the Al 2O3/SiO2 ratio of 3, which is the traditional stoichiometric ratio for the mullite phase synthesis, the matrix of the synthesized sample is represented by the amorphous phase penetrated by filamentary single crystals of mullite with the average length of 3.3 μm and 0.86 μm thickness. It is found that the transition layer between these phases has a glass-ceramic structure, which is consistent with the results of the X-ray phase analysis.

High temperature oxidation behavior of polymer-derived SiBNC–Al ceramics

Modification with metallic elements improves the performance of polymer-derived SiBNC ceramics in high temperature aerobic environments. However, there is still need for a deep-set comprehension of the effects of metal modifiers on the phase composition, microstructural evolution of these ceramics. To elucidate, the changes in the internal crystal structures of three Aluminium modified SiBNC ceramics (SiBNC–Al) subsequent to oxidative treatment in flowing air (1200–1600°C) at different times are reported. The binding states and free carbon systems of the SiBNC–Al ceramics after high-temperature oxidation were examined by XPS and Raman spectroscopy. SiBNC–Al ceramics showed a sustained amorphous state after oxidative treatment at 1200°C. After oxidative exposure at 1400°C for 2 h, the mass retention of SiBNC–Al containing the least to the highest Al content (Al 5c, Al 3c, Al 1c, respectively), was 99.4 wt%, 96.3 wt%, and 98.6 wt%. Meanwhile, the interior of modified SiBNC–Al was comprised of β-Si3N4, β-SiC, mixed AlN(+SiC) and Mullite phases, after oxidation at 1500°C for 2 h. And the surface morphology of Al 3c at different oxidation temperatures for 8 h was analyzed by SEM, which proved that the thin oxide layer can effectively prevent further oxidation inside the ceramics.

Wear behavior and microstructure of alumina-mullite-zirconia composites prepared by a novel method: Coating of zircon powder by aluminum alkoxide

The formation of the mullite phase is the main challenge in the preparation of alumina-mullite-zirconia (AMZ) composites. To overcome this limitation, a novel method based on the coating of zircon powder with aluminum alkoxide was proposed in this study. Reaction sintering of alumina and coated zircon was carried out at 1630 °C for 3 h. The microstructural, physical, mechanical, and tribological properties of samples were compared with the conventional AMZ composites prepared by common mixing of alumina and zircon. The microstructural analysis indicated the higher alumina phase of the sample prepared with the conventional method. On contrary, the samples prepared with the proposed method included higher percentages of mullite phase. In terms of mechanical properties, the conventional AMZ samples performed better. However, due to the beneficial effect of the mullite phase in tribological applications, the samples prepared with this new method show superior wear resistance. Especially, the samples prepared from 30 wt% aluminum alkoxide exhibited the best wear resistance. The delamination and adhesive wear mechanisms govern the wear process.

Self-healing diamond/geopolymer composites fabricated by extrusion-based additive manufacturing

Geopolymers are easily molded and mixed with various additives to form composite materials with desired functions. In this study, the gradient diamond/geopolymer composites (DGP) are fabricated based on the extrusion-based AM technique. Diamond disturbs the chain structure of the geopolymers, making the slurry easier to extrude with delayed solidification time and reaction rate. The interfacial characterization shows that a larger volume secondary mullite are formed from mullite phase under the condition of sufficient thermal transform from the diamond, thus achieving the self-healing process of pores and cracks at room temperature. The results of heat treatment of the DGP prove that the diamond effectively optimizes the thermal stability with fewer pores and cracks. Self-healing of damage in engineering materials can be achieved by reducing the crack widths during service process, which highly extends the life cycle and saves the operating cost. 3D printed geopolymer/diamond composites are successfully fabricated with self-healing ability and thermal stability. • Diamond/geopolymer (DGP) composites fabricated by extrusion-based additive manufacturing. • The DGP has a role in effectively delaying solidification time and increasing printing efficiency. • The DGP enables self-healing process of pores and cracks at room temperature. • The DGP could effectively enhance the stability of the sintered parts at 1200 °C.

On the role of continuity in statistical nanoindentation of composite microstructures

AbstractThe validity of the statistical nanoindentation (SNI) technique for cementitious materials has been questioned by numerous researchers; however, it is still a commonly used method in literature. This study revisits assumptions pertaining to continuum mechanics of the method by using a well‐established selective SNI method to evaluate continuity in the mechanical response of each indent. Ordinary portland cement (OPC) was investigated alongside a two‐phase aluminosilicate ceramic (Al–Si). Filtering for continuity of indents eliminated a majority of indents in each sample. The indents meeting continuity requirements in the OPC sample had moduli values in the range of documented calcium silicate hydrates and portlandite—the predominant hydration phases in OPC. In the Al–Si sample, 73% of continuous indents were assigned to a mullite phase, although the chemical analysis showed only 42% mullite. This was attributed to the embedded morphology of the mullite phase, which made it more susceptible to structural compliance. These observations suggest that SNI may be ineffective for measuring the mechanical properties of individual phases in a microstructure if they are not prolific enough to exhibit a continuous indent response. Discontinuous indents due to microstructural interaction between phases were also shown to have a potential influence on the number of clusters (i.e., phases) suggested by the deconvolution algorithms.

Recycling of aluminum dross and silica fume wastes for production of mullite-containing ceramics: Powder preparation, sinterability and properties

The improper disposal of industrial wastes causes environmental pollution so their recycling for fabrication of new products became an interesting research issue. In this work, sintered mullite-containing ceramics were prepared from aluminum dross and silica fume (up to 40 wt%) waste materials after sintering up to 1500 °C. Before sintering, the starting waste materials were converted into nano powders by mechanical milling alloying method up to 15 h. The obtained waste nano powders were investigated using different techniques as X-ray diffraction (XRD), transmission electron microscope (TEM) and scanning electron microscope (SEM). On the other hand, phase identification by XRD, physical properties determination (bulk density and apparent porosity), microstructure by SEM, mechanical and electrical properties of sintered bodies were investigated. The results revealed that mullite phase was formed in higher amounts with increasing both sintering temperature (1500 °C) and silica fume content. At 1300 °C, amorphous mullite was formed in addition to the alumina phase. It is also noted that the apparent porosity and bulk density were reduced with increasing silica content. However, they exhibited opposite trend when the temperature increased from 1300 into 1500 °C. Moreover, with increasing the mullite content, the microhardness, compressive strength, Younges modulus and electrical conductivity were decreased and reached 10.2 GPa, 216.9 MPa, 119.7 GPa and 4.9 × 10 −12 S/m, respectively, for the sample that contained higher amount of mullite, while the fracture toughness was improved and reached to 3.44 MPa m0.5.

Fabrication of SiC foam ceramics at a low sintering temperature by adding fly ash

Silicon carbide (SiC) foam ceramics (SFC) have been widely used in various industries owing to their excellent mechanical properties at elevated temperatures. However, fabricating a qualified product at a low sintering temperature is a challenge because of the strong covalent nature of the Si–C bond. In this study, we successfully fabricated a SFC at a low sintering temperature (1150 °C) by adding fly ash (FA) using the polyurethane replication method. The effects of sintering temperature and FA content on the mechanical performance of the ceramics were systematically studied. The phase composition and microstructure of the SFC were characterized using X-ray diffraction and scanning electron microscopy. At 1150 °C, an SFC with 30 wt% FA exhibited optimal properties, i.e., a porosity of 64.43%, bulk density of 0.89 g/cm3, and bending strength of 8.34 MPa. As a sintering aid, FA promoted the formation of the mullite phase at low sintering temperatures, which enhanced the anticorrosion and anti-cracking performance of the SFC. Therefore, adding FA to SiC significantly lowers the sintering temperature and reduces the fabrication cost associated with the SFC. Consequently, its commercial application is considerably enhanced.

Effects of AlN inorganic binder on the properties of porous Si3N4 ceramics prepared by selective laser sintering

Porous Si3N4 ceramics are widely used in the aerospace field due to its lightweight, high-strength, and high wave transmission. Traditional manufacturing methods are difficult to fabricate complex structural and functional ceramic parts. In this paper, selective laser sintering (SLS) technology was applied to prepare porous Si3N4 ceramics using AlN as an inorganic binder. And the effects of AlN content on the properties of the obtained ceramic samples were explored. As the AlN content increased, nano-Al2O3 and nano-SiO2 formed the eutectic liquid phase, enhancing the sintering densification and phase transformation of Si3N4 poly-hollow microspheres (PHMs). The island-like partial densification structures in Si3N4 green bodies increased. During the high-temperature sintering, the eutectic liquid phase partially transformed into the mullite phase or reacted with AlN and Si3N4 to form the Sialon phase. With the increase of AlN content, the fracture mode of Si3N4 ceramics changed from fracturing along PHMs to fracturing across PHMs. The bonding depth between PHMs increased and the connection between the grains was tighter, so the Si3N4 ceramics became denser. With the increase of AlN addition, the total porosity of the porous Si3N4 ceramics tended to decrease and the flexural strength gradually increased. When AlN content was 20 wt%, the total porosity and the flexural strength were 33.6% and 23.9 MPa, respectively. The addition of AlN inorganic binder was carried out to develop a novel way to prepare high-performance porous Si3N4 ceramics by SLS.

Partial substitution of feldspar by alkaline-rich materials in the electrical porcelain insulator for reduction of processing temperature

Porcelain is the most widely used overhead power-line insulator. The demands for porcelain insulators have increased dramatically owing to a sharp increase in the electric power demand and supply. Usually, porcelain production demands high sintering temperatures. Herein, an electrical porcelain insulator was produced from Bombowha clay and Arero quartz and partially replaced feldspar with sodium carbonate at a reduced processing temperature. The porcelain samples were prepared by fixing the clay and quartz amount 45 and 10 wt%, respectively, and the portion of feldspar was replaced by 5, 7.5, and 10 wt% of alkaline-rich sodium carbonate. The desired composition was milled, shaped, and finally sintered at 1000, 1100, and 1200 °C. The XRD and SEM results show the early formation of quartz and mullite phases at 1000 °C, which determine the mechanical and dielectric strengths of the porcelains. The dielectric strength of the samples increases with increasing the alkaline-rich sodium carbonate content owing to the vitrification and needle-shaped mullite formation. The porcelain sample with 10 wt% of Na2CO3 content and a sintering temperature of 1200 °C has an optimum dielectric strength of 7.60 kV mm−1.

Equilibrium Phase Relations for a SiO2-Al2O3-FeOx System at 1300 °C and 1400 °C in Air

A long-term fundamental study for the construction of the thermodynamic database of a metallurgical slag system has been proposed. In the present work, the equilibrium phase relations for the key ternary SiO2-Al2O3-FeOx system at 1300 °C and 1400 °C in air were experimentally determined by the equilibrium-quenching technique, followed by X-ray Photoelectron Spectroscopy and Scanning Electron Microscope equipped with an Energy Dispersive X-ray Spectrometer analysis. The oxidation states of Fe2O3 and Fe3O4 were confirmed at 1300 °C and 1400 °C, respectively, from both XPS detection and FactSage calculation. Within the high-SiO2 composition range, the solid phases of silica, mullite, magnetite and ferric oxide were confirmed as the equilibrium phases. Based on the equilibrium compositions, the 1300 °C and 1400 °C isotherms were projected onto a SiO2-Al2O3-FeOx quasi-ternary phase diagram; however, obvious discrepancies with about a 20 °C difference were confirmed from further comparison with the predictions given by FactSage, indicating that more efforts are needed for the updating of the current thermodynamic database relating to metallurgical slag oxide systems.

Preparation of Porous Ceramic Building Decoration Materials by Foaming Method and Research on Nanomechanical Properties.

Because of its excellent properties, mullite porous ceramics are widely used in thermal insulation materials, catalyst carriers, gas-liquid filtration, separation materials, etc. At the same time, zirconia not only has the advantages of high melting point, good chemical stability, and high strength but also can significantly improve the strength of ceramics through phase transformation and particle dispersion in the matrix and is widely used in the reinforcement of ceramics. In this paper, using mullite powder as the raw material, Al2O3 and SiO2/ZrSiO4 as the starting material for the mullite self-bonding phase, and AlF3·3H2O, ZrO2, and Y2O3 as additives, the zirconia-reinforced mullite was prepared by the foaming-injection method. The volume density, linear shrinkage rate, microstructure, room temperature, etc. of nanozirconia-reinforced mullite porous ceramics were studied by the amount of the foaming agent, the amount of mullite self-bonding phase powder, the type and amount of additives, etc. Effects of mechanical properties and thermal conductivity were also analyzed. The research results show that zirconia-reinforced mullite porous ceramics were prepared with mullite powder and 6 wt% AlF3·3H2O as raw materials, and ZrO2 and Y2O3 as additives. Adding an appropriate amount of ZrO2 and Y2O3 can significantly improve the mechanical properties of porous ceramics. When ZrO2 is 6 wt% and Y2O3 is 8 wt%, the porosity is 66.4% and the flexural strength and compressive strength of porous ceramics with a large pore size of 168 μm can reach 14.3 MPa and 36.3 MPa, respectively, which are obviously better than the strength of mullite porous ceramics without adding Y2O3 (flexural strength 11.3 MPa, nanocompressive strength 29.4 MPa).

Ag-modified SmMn2O5 catalysts for CO and C3H8 oxidation

A series of Sm-Mn oxides (SmMnO3, SmMn2O5 and Sm0.9Ag0.1Mn2O5) of perovskite-type and mullite crystal phases were synthesized for the catalytic oxidation of CO and C3H8. The Sm0.9Ag0.1Mn2O5 composition showed the highest catalytic activity among the series of solids, especially for the CO oxidation to CO2 with T50 and T90 values of 60 and 95 °C, respectively. The catalysts were characterized by powder XRD, Raman, BET, XPS, and H2-TPR. It was found that the catalytic performance of the solids was correlated well with their redox properties. Synergetic effects between Ag-related species and the mullite phase resulted in more active surface oxygen species and remarkably lowered the reduction temperature of the Sm0.9Ag0.1Mn2O5 solid.

Preparation of mullite/NbN composites through spark plasma sintering

The main objective of this article is to obtain reaction sintered mullite based ceramics through spark plasma sintering process. 5, 10 and 15 wt% NbN particles were mixed with kaolinite and alumina powders as mullite precursor through a wet milling process. The mullite ceramic and composites were fabricated by spark plasma sintering (SPS) method at 1350 °C with initial and final applied pressure of 10 and 50 MPa, respectively. All of prepared composites showed relative density higher than 99% of theoretical density as well as mullite ceramic. The XRD patterns obtained from sintered composites demonstrated dominant crystalline phase of mullite and NbN and also some low-intensity of alumina peaks were observed. The FESEM images of sintered composites illustrated uniform distribution of reinforcement particles for 5 and 10 wt% addition of NbN. While using 15 wt% NbN reinforcement phase lead to form some agglomerates areas. The optimum mechanical properties were obtained for composites containing 10 wt% NbN as bending strength of 441 ± 36 MPa, Vickers hardness of 17.89 ± 0.61 GPa and fracture toughness of 3.79 ± 0.12 MPa m1/2.

In situ formation of mullite strengthened SiC porous ceramics via gelcasting with high strength and good alkali resistance

AbstractMullite‐bonded porous SiC ceramics sintered in air by gelcasting are still challenges due to the high porosity induced severe oxidation of SiC, which results in the formation of large amount of detrimental cristobalite phase. Here in this work, small amounts of Y2O3 and CaF2 were added in SiC and Al(OH)3 raw materials as sintering additives for the in situ growth of mullite reinforcement. This additive system promoted the reaction between oxidation‐derived SiO2 from SiC and Al2O3 decomposed from Al(OH)3 to mullite phase. Almost no cristobalite phase was detected when sintered at 1450℃/2 h with CaF2 addition of more than 2.0 wt%. Mullite whisker reinforcement was in situ formed due to the gas reaction mechanism caused by CaF2 addition. Thus obtained porous SiC ceramics exhibited a flexural strength of 67.6 MPa at porosity of 41.3%, which maintained exceeding 36 MPa after 8 h corrosion in 10 wt% NaOH 80℃ solution, being the best performance up to now. This high performance of porous SiC was attributed to the additive induces proper phase control and in situ formation of whisker‐like mullite reinforcement.

Fabrication and characterization of ceramic hollow shaped from the local kaolin intended for the filtration

ABSTRACT Ceramic membranes are one of the emerging separation technologies with extremely high separation factors. In this work, natural Kaolin clay collected from the western of Algeria was characterized in detail to see its feasibility in a ceramic membrane preparation. The ceramic membrane was prepared by solid-state reactive firing under the slip casting method. The aim is to favor the mullite phase, once the alumina is added a part will be dispersed in the mullite matrix to form a mullite-alumina composite. The mineralogical, morphological structure, particle size distribution, thermal stability, and chemical composition of prepared alumina oxide membrane were carried out using several techniques. They reveal the apparition of two main phases the mullite and the alumina. The kaolin provides the membrane with a well homogeneous morphology, good hydrophobicity, and thermal stability. The obtained membrane presented a mesoporous membrane character that can use successfully for ultrafiltration applications..

High-performance mullite fibrous ceramic filter enhanced by composite sintering aids for dust-laden gas filtration

Fibrous ceramic filter is one of the promising candidates for high-temperature gas cleaning but is constrained seriously by its mechanical strength. In this work, we successfully prepared a mullite fibrous ceramic filter (MFCF) with high bending strength reinforced by a composite sintering aid of kaolin and feldspar. The bending strength of the MFCF can reach up to 13.1 MPa that was much higher than those reported in the literature. The mullite phase was formed on the neck during the sintering process and greatly enhanced the bending strength as can be characterized by X-ray diffraction (XRD) patterns and three-point bending test. These ceramic filters at the optimized fabrication conditions have a porosity of 61.8%, an average pore size of 14.8 μm, and nitrogen permeance of above 673 m3·m−2·h−1·kPa−1, respectively. Moreover, the mullite-fiber-based filters exhibited satisfactory thermal shock resistance and corrosion resistance after experiencing thermal fatigue and acid corrosion process. In addition, these prepared ceramic filters still showed a removal efficiency of above 99.9% for PM2.5. Therefore, the MFCF reported in this work exhibited great potential for industrial hot gas filtration.