Ceramic Foam Research Articles

A study on ceramic sintering preparation process and properties with the addition of silicon carbide foaming agent

Foamed ceramics are widely used in construction as a building material. This article used potassium feldspar tailings as the primary raw material and added a silicon carbide (SiC) foaming agent to prepare samples through a sintering process. The impact of three factors − SiC content, sintering temperature and heat preservation time − on sample properties (such as bulk density and water absorption rate) was analyzed using a single-factor variable method. It was found that the increase in SiC content, sintering temperature, and heat preservation time increased pores inside the sample, thereby leading to a higher water absorption rate, lower compressive strength and higher mass loss rate, i.e., decreased sample performance. Overall, the optimal sintering process parameters were as follows: a SiC content of 1.0 wt%, a sintering temperature of 1,250℃ and a heat preservation time of 30 minutes. Under these conditions, the obtained sample had a bulk density of 0.54 g/cm3, a water absorption rate of 13.45%, a compressive strength of 4.75 MPa, a thermal conductivity of 0.06 W/(m·K) and an acid resistance mass loss of 1.21%, exhibiting the optimal performance. The experimental results provide appropriate SiC content and sintering parameters that can be applied in practice to obtain higher-performance foam ceramics.

Optimized Development of High-Porosity Structural and Thermal Insulation Foam Ceramics Based on Local Natural and Technogenic Raw Materials

This study explores the optimization of foam ceramic materials through experimental research and mathematical modeling. The goal was to enhance mechanical strength, thermal insulation, porosity, water absorption, and density by adjusting composition and firing conditions. Regression analysis and response surface methodology were used to assess the effects of loam, fly ash content, and the firing temperature. The optimal composition of 60–65% loam, 10% fly ash, and a firing temperature of 950–1000 °C yielded foam ceramics with a bulk density of 680–700 kg/m3, a compressive strength of 3.5–4 MPa, and a thermal conductivity of 0.135–0.140 W/(m·K). Controlled porosity (70–72%) enhanced insulation while maintaining structural integrity. X-ray diffraction confirmed mullite, quartz, and cristobalite phases, with mullite improving mechanical properties. This research demonstrates the potential of optimized foam ceramics for energy-efficient construction. Mathematical modeling and experimental validation provide a pathway for developing lightweight, high-performance ceramic materials. Future work should refine sintering processes, explore new additives, and evaluate the long-term performance.

Co–upcycling hazardous solid wastes of MSWI fly ash and secondary aluminum ash into iron and glass ceramic foams

Co–upcycling hazardous solid wastes of MSWI fly ash and secondary aluminum ash into iron and glass ceramic foams

Multiple Charge Carriers Manipulation Toward Semiconductive Ceramic Nanocomposites for Corrosion-Resistant Electromagnetic Wave Absorption.

The modulation of transport properties in ceramic-based semiconductors can be used to optimize the electromagnetic response mechanism and performance. A semiconductor ceramic foam interlayer wall (SCFW) is designed by a physical vapor deposition method. The interlayer structural SCFW is composed of semiconductor-insulator-semiconductor layers, incorporating a composite system of SiC, Al4.8Si1.2O9.6, and Al2O3. Moreover, the hierarchical network structure of the foam interlayer wall is controlled by the pyrolysis-deposition kinetic process. Electrons and holes are transported through the heterojunctions between SiC and Al4.8Si1.2O9.6, achieving effective charge relaxation. The Al2O3 matrix provides lightweight properties (density of 0.967 gcm-3), while the hierarchical network structure determines the excellent electromagnetic wave (EMW) absorption performance of the SCFW, with an effective bandwidth up to 14.8GHz under electromagnetic response (minimum reflection loss RLmin = -50.6dB). the SCFW has been proven to exhibit corrosion resistance and thermal insulation properties, with a thermal conductivity up to 0.025 Wm-1K-1. This study provides valuable insights into the structural design and dielectric property optimization of ceramic-based semiconductor nanocomposites, which leads to strong polarization loss, opening new avenues for the application of EMW absorbers, and the EMW absorption mechanism of ceramics.

Near-zero firing shrinkage and high-strength CaAl12O19 ceramic foams fabricated via aluminum microsphere hollowing

Near-zero firing shrinkage and high-strength CaAl12O19 ceramic foams fabricated via aluminum microsphere hollowing

Development and fabrication of ceramic foam supported catalysts for alkylation of anisole

Development and fabrication of ceramic foam supported catalysts for alkylation of anisole

Synthesis and characterization of photocatalytic ceramic foams for the degradation of acetaminophen

Synthesis and characterization of photocatalytic ceramic foams for the degradation of acetaminophen

Alumina ceramic foams with an open hierarchical pore structure prepared by oxidation hollowing of aluminum

AbstractThe application of high‐porosity open‐cell alumina ceramic foams has been hindered due to their significant sintering shrinkage and low strength. In this study, alumina ceramic foams with open‐cell and hierarchical structures were fabricated by utilizing spherical aluminum powder as raw material and polyurethane sponge as a template. Based on the Kirkendall effect, the near‐net size fabrication of alumina ceramic foams was realized through the expansion generated by the oxidation hollowing of sphere aluminum powder, and the mechanical properties of ceramic foams were optimized by constructing micrometer alumina hollow spheres. The oxidation hollowing mechanism of sphere aluminum powder was investigated using X‐ray diffraction, Raman spectroscopy, and scanning electron microscope, the possible reaction process is Al → γ‐Al2O3 → θ‐Al2O3 → α‐Al2O3. Cracks induced by sintering shrinkage caused a sharp decline in the mechanical properties of ceramic foams when the sintering temperature exceeded 1100°C. By adjusting impregnation times of foam slurry, alumina foams with a bulk density of 0.23–0.48 g/cm3, total porosity of 94.3%–87.8%, compressive strength of 0.79–1.35 MPa, and sintering expansion of 0.76%–1.40% were prepared at 1100°C. This study provided a feasible strategy and theoretical basis for optimizing the mechanical properties of open‐cell alumina ceramic foams.

Optimizing electrochemical removal of perfluorooctanoic acid in landfill leachate using ceramic carbon foam electrodes by coupling CFD simulation and reactor design.

Optimizing electrochemical removal of perfluorooctanoic acid in landfill leachate using ceramic carbon foam electrodes by coupling CFD simulation and reactor design.

The Influence of Rare Earth Metals on the Microstructure and Mechanical Properties of 220 and 356.1 Alloys for Automotive Industry.

Application of rare earths (RE) as grain refiners is well-known in the technology of aluminum alloys for the automotive industry. In the current study, Al-2.4%Cu-0.4%Mg alloy (coded 220) and Al-7.5%Si-0.35%Mg alloy (coded 356.1), were prepared by melting each alloy in a resistance furnace. Strontium (Sr) was used as a modifier, while titanium boride (TiB2) was added as a grain refiner. Measured amounts of Ce and La were added to both alloys (max. 1 wt.%). The alloy melts were poured in a preheated metallic mold. The main part of the study was conducted on tensile testing at room temperature. The results show that although RE would cause grain refining to be about 30-40% through the constitutional undercooling mechanism, grain refining with TiB2 would lead to approximately 90% refining (heterogenous nucleation mechanism). The addition of high purity Ce or La (99.9% purity) has no modification effect regardless of the alloy composition or the concentration of RE. Depending on the alloy ductility, the addition of 0.2 wt.%RE has a hardening effect that causes precipitation of RE in the form of dispersoids (300-700 nm). However, this increase vanishes with the decrease in alloy ductility, i.e., with T6 treatment, due to intensive precipitation of ultra-fine coherent Mg2Si-phase particles. There is no definite distinction in the behavior of Ce or La in terms of their high affinity to interact with other transition elements in the matrix, particularly Ti, Fe, Cu, and Sr. When the melt was properly degassed using high-purity argon and filtered using a 20 ppi ceramic foam filter, prior to pouring the liquid metal into the mold sprue, no measurable number of RE oxides was observed. In conclusion, the application of RE to aluminum castings would only lead to formation of a significant volume fraction of brittle intermetallics. In Ti-free alloys, identification of Ce- or La-intermetallics is doubtful due to the fairly thin thickness of the precipitated platelets (about 1 µm) and the possibility that most of the reported Al, Si, and other elements make the reported values for RE rather ambiguous.

Preparation and corrosion resistance to cathode materials for lithium‐ion batteries of CA6 foam ceramics

AbstractCA6 foam ceramics (CA6‐FCs) with CA6 as the main crystalline phase were prepared by adding CA6 powder through gel casting process, which reduced the severe shrinkage in the reaction synthesis process of CA6. This simple preparation process can realize the industrial production of CA6‐FCs. The linear change and physical properties of CA6‐FCs can be controlled by adjusting the additional amount of CA6 powder and the solid content of the slurry. The corrosion resistance of CA6‐FCs is better than that of the current mainstream mullite thermal insulation materials in lithium‐ion battery cathode materials. Through the simple process of this study, on the basis of industrial production, CA6‐FCs can replace mullite lightweight thermal insulation materials to improve the alkali corrosion resistance, service life, and maintain production safety of kiln lining.

Research on multi-source microstructure image recognition of foam ceramics using convolutional network combine with frequency domain

Foam ceramics are widely used in industrial applications due to their unique properties, including high porosity, lightweight, and high-temperature resistance. However, their complex microstructure presents significant challenges for image analysis. Traditional machine learning methods often fall short in capturing both global feature dependencies and detailed representations. To address this, a novel artificial intelligence recognition model, FD-Conv, is proposed, which combines the global information processing capabilities of Transformers with the local feature extraction strengths of convolutional neural networks. Additionally, a frequency domain block detail enhancement mechanism is introduced to improve recognition accuracy. Experimental results demonstrate that the FD-Conv model enhances recognition accuracy by at least 7.6% compared to state-of-the-art methods. Furthermore, the model effectively identifies foam ceramics with varying compositions and formulations and quantifies their microstructural phase characteristics. This research aims to advance the application of foam ceramic microstructure image analysis by improving recognition accuracy, particularly in multi-source microscopic image feature learning and pattern recognition.

Fabrication of SiC-Al2O3 foam ceramic and its application in fluoride-containing water

Fabrication of SiC-Al2O3 foam ceramic and its application in fluoride-containing water

Controlling the permeability of the particle‐stabilized ceramic foams with polymethyl methacrylate microsphere as pore‐forming agent

AbstractOpen‐cell ceramic foams with controllable cell connectivity were fabricated by polymethyl methacrylate (PMMA) microspheres as pore‐forming agent combined with particle‐stabilized foaming method. In order to adjust the open‐cell structures of ceramic foams, PMMA microspheres with distinct particle sizes and contents were used. The results indicate that the bubble‐derived pores in the prepared ceramic foams were interconnected by microsphere‐derived pores within cell walls, and the average size and volume fraction of microsphere‐derived pores and bubble‐derived pores could be tailored by adjusting the particle size and content of PMMA microspheres. The impacts of open‐cell structures on connectivity were described in terms of permeability in this study. The open‐cell ceramic foams obtained using larger PMMA particle size and content exhibited larger Darcian and non‐Darcian permeability constants due to the increase of the size and volume fraction of microsphere‐derived pores. The ratio of Darcian and non‐Darcian permeability constant represents the individual contribution of viscous and inertial effects to the total pressure drop during the permeation process that are strongly dependent on the microsphere‐derived pore size and pore volume fraction. The Darcian and non‐Darcian constants in this study were in the range of 3.54 × 10−12 to 4.09 × 10−11 m2 and 3.05 × 10−7 to 5.10 × 10−6 m, respectively. These results are of practical value for the preparation and optimization of ceramic foams in applications requiring open‐cell structures.

Preparation and Microwave-Absorbing Property of Solid-Waste-Derived Ceramic Foam

Recently, electromagnetic wave (EMW)-absorbing materials have obtained increasing attention for both military and civil applications. This study adopted the powder sintering method and the concept of recycled wastes in fabricating functional ceramic foam (CF). Firstly, a ceramic green body composed of pulverized granite residues, waste glass, and a foaming agent was sintered. The influence of the sintering temperature and SiC addition on CF was investigated, and then surface graphitization post-treatment of CF was performed as well. The truly enhanced compressive strength and EMW-absorbing property of surface graphitization ceramic foam (SG-CF) with a homogeneous porous structure was realized in the present work, which is promising as a candidate in EMW absorption systems.

Effect of Various Foaming Agents on Ceramic Foam from Solid Waste

Due to the significant amount of solid waste generated annually in China, the rational use of these wastes has become increasingly important. The production of foam ceramics is considered an effective method for the large-scale utilization of such solid waste. In this study, granite sawing mud was selected as the raw material, with SiC and MnO2 serving as foaming agent to prepare foam ceramics. The foaming behavior of sintered samples using different foaming agent was investigated to determine the most suitable type and amount of foaming agent for obtaining foam ceramics with excellent pore structures. Additionally, the effects of the foaming agent on the pore structure and physical mechanical properties of the foam ceramics were studied in detail. The results showed that SiC and MnO2 both resulted in the pronounced expansion to different extent, and increasing the content of foaming agent enhances foam expansion. The best dosage of SiC was 1%, the optimum additive amount of MnO2 is 2–3%. For SiC, the oxidation reduction reaction occurred between SiC and O2 to generate CO2/CO. For MnO2, firstly, the reduction of MnO2 to Mn2O3 occurred, and then the Mn2O3 dissolved in the glass melt and, subsequently, Mn3+ was reduced to Mn2+, leading to gas formation and foaming. Under the same dosage of foaming agent and preparation conditions, the sample prepared with SiC as the blowing agent has higher compressive strength, lower water absorption, and a more uniform pore structure.

OPTIMIZING VOLUMETRIC SOLAR AIR RECEIVERS: NUMERICAL ANALYSIS OF POROSITY AND FLOW EFFECTS ON TEMPERATURE DISTRIBUTION

Ceramic foams are promising as absorber materials for volumetric solar receivers (VSR) in concentrated solar thermal power (CSP) systems. The temperature distribution of the VSR is very important to ensure that it operates efficiently and steadily. This study aims to simulate and analyze the temperature distribution within a VSR considering both the solid and fluid phases. The modelling of the open-cell volumetric receiver employs combined volume-averaged equations, assuming the ceramic foam to possess isotropic and homogeneous properties. To assess the pressure-drop in the VSR a non-Darcian model is adopted. A local thermal non-equilibrium (LTNE) model is implemented to describe the energy equations for both the solid and fluid phases. Additionally, the study considers the influence of solar radiation as a heat source on the solid phase. The heat transfer between the surfaces of the volumetric solar air receiver's struts is calculated using the P1 model. At the same time, a macroscopic approach is utilized to evaluate the thermal profile of the ceramic foam. This study also aims to assess the impact of the VSR's porosity and cell size variation on the outlet air temperature. Moreover, the flow scheme of the flowing air, concerning the incident of concentrated radiation, is considered.

Synergistic preparation and properties of ceramic foams from wolframite tailings and high-borosilicate waste glass

Synergistic preparation and properties of ceramic foams from wolframite tailings and high-borosilicate waste glass

The Effect of Water Glass Content on the Morphology and Thermal Properties of Anorthite-Based Ceramic Foam Filter for Aluminum Alloy Casting

The Effect of Water Glass Content on the Morphology and Thermal Properties of Anorthite-Based Ceramic Foam Filter for Aluminum Alloy Casting

Ultralight corundum-mullite-zirconia composite ceramic foams prepared by triphasic nanoparticle stabilized foams with improved thermal shock resistance

Ultralight corundum-mullite-zirconia composite ceramic foams prepared by triphasic nanoparticle stabilized foams with improved thermal shock resistance