Showing papers on "Ceramic matrix composite published in 2023"

Direct additive manufacturing of TiCp reinforced Al2O3-ZrO2 eutectic functionally graded ceramics by laser directed energy deposition

Abstract: Laser directed energy deposition (LDED) provides an ideal manufacturing technique to produce ceramic matrix composites, which are endows with superior and customizable mechanical properties by the reinforcement of gradient distribution of rigid particles. In this paper, we for the first time manufactured TiCp reinforced Al2O3-ZrO2 eutectic functionally graded ceramics with two different transition modes using LDED. The results show that the gradient transition realizes gradually increase of TiCp particles in Al2O3-ZrO2 eutectic matrix. With the increase of TiCp content, the morphology of Al2O3-ZrO2 eutectic matrix changes from lamellar or rod-shaped to irregular shape. Meanwhile, LDED realizes controllable fabrication of properties in different positions of gradient materials, and the wear resistance of TiCp rich regions has increased by 43.4% compared with pure Al2O3-ZrO2 region.

Ceramic Matrix Composites for Aero Engine Applications—A Review

Abstract: Ceramic matrix materials have attracted great attention from researchers and industry due to their material properties. When used in engineering systems, and especially in aero-engine applications, they can result in reduced weight, higher temperature capability, and/or reduced cooling needs, each of which increases efficiency. This is where high-temperature ceramics have made considerable progress, and ceramic matrix composites (CMCs) are in the foreground. CMCs are classified into non-oxide and oxide-based ones. Both families have material types that have a high potential for use in high-temperature propulsion applications. The oxide materials discussed will focus on alumina and aluminosilicate/mullite base material families, whereas for non-oxides, carbon, silicon carbide, titanium carbide, and tungsten carbide CMC material families will be discussed and analyzed. Typical oxide-based ones are composed of an oxide fiber and oxide matrix (Ox-Ox). Some of the most common oxide subcategories are alumina, beryllia, ceria, and zirconia ceramics. On the other hand, the largest number of non-oxides are technical ceramics that are classified as inorganic, non-metallic materials. The most well-known non-oxide subcategories are carbides, borides, nitrides, and silicides. These matrix composites are used, for example, in combustion liners of gas turbine engines and exhaust nozzles. Until now, a thorough study on the available oxide and non-oxide-based CMCs for such applications has not been presented. This paper will focus on assessing a literature survey of the available oxide and non-oxide ceramic matrix composite materials in terms of mechanical and thermal properties, as well as the classification and fabrication methods of those CMCs. The available manufacturing and fabrication processes are reviewed and compared. Finally, the paper presents a research and development roadmap for increasing the maturity of these materials allowing for the wider adoption of aero-engine applications.

A Review on Ceramic Matrix Composites and Environmental Barrier Coatings for Aero-Engine: Material Development and Failure Analysis

Abstract: Ceramic matrix composites with environmental barrier coatings (CMC/EBCs) are the most promising material solution for hot section components of aero-engines. It is necessary to access relevant information and knowledge of the physical properties of various CMC and EBCs, the characteristics of defects and damages, and relevant failure mechanisms. Then, effective failure prediction models can be established. Individually assessing the failure of CMC and EBCs is not a simple task. Models considering the synergetic effect of coating properties and substrate fibrous architecture are more reasonable and more challenging. This paper offers a review and a detailed description of the materials features, failure mechanism, and failure modeling for both CMC substrate and EBC coatings. The various methods for failure analyses and their pros and cons are discussed. General remarks on technical development for failure modeling are summarized subsequently.

Evolution from microfibers to nanofibers toward next-generation ceramic matrix composites: A review

Abstract: Ceramic matrix composites (CMCs) are designed to overcome the main drawback of monolithic ceramics, namely their brittleness, and are constituently expressed as a continuous phase, or matrix, a distributed phase, commonly referred to as the reinforcing fibers, and also an interphase layer or coating layer between them. In this regard, there is a necessity to understand the principles for choosing the reinforcing fibers and designing the fiber–matrix interfaces. Hence, an attempt is made to review the recent progresses on ceramic micro-nano fibers and their effect on the interfaces in CMCs. The development trend for CMCs is discussed, especially the future CMCs based on ceramic micro-nano fibers, including the strengthening and interface construction concerning with these fibers. • A brief review of current progress in the field of ceramic matrix composites is presented. • Two essential issues of fiber candidates and interface design are discussed. • Evolution from microfibers to nanofibers toward next-generation ceramic matrix composites is prospected.

Preparation and properties of Ti3SiC2 preform reinforced SiC ceramic matrix composites

Abstract: Ti3SiC2 preform reinforced SiC ceramic matrix composites (Ti3SiC2/SiC) were successfully fabricated through a novel near-net-shape process strategy combining molten salt synthesis with subsequent polymer infiltration and pyrolysis (PIP) for the first time. The effects of temperature and molten salt ratio on the phase composition, pore structure, and flexural strength of Ti3SiC2 preform were investigated in detail. The morphology and microstructure evolution of the composites during the PIP process were observed by SEM and TEM. The mechanical properties, electromagnetic interference shielding effectiveness (EMI SE) and thermal conductivity of Ti3SiC2/SiC were significantly improved compared to PDC-SiC, which benefits from the connected network skeleton of Ti3SiC2 preform. The flexural strength and fracture toughness of Ti3SiC2/SiC are 198.7 MPa and 4.5 MPa∙m1/2. The EMI SE remains above 30 dB covering the entire X-band and its average value is 46.92 dB. The thermal conductivity is 6-7 W/(m·k) (25 °C to 1000 °C).

Significant improvement of ultra-high temperature oxidation resistance of C/SiC composites upon matrix modification by SiHfBCN ceramics

Abstract: Advanced C/SiC-SiHfBCN composites were prepared by modification of the matrix of C/SiC composites with single-source-precursor derived SiHfBCN ceramics. Ultra-high temperature oxidation behavior of the C/SiC-SiHfBCN composites under laser heating were systematically studied. The influence of temperature, preform structure and precursor on oxidation resistance of the composites were analyzed. The results revealed that the preform structure and precursor can influence the oxidation behavior of C/SiC-SiHfBCN composites by effecting its thermal conductivity in the thickness direction. The Hf-containing oxide layer formed during ultra-high temperature oxidation test can effectively protect the internal carbon fibers from being oxidized. Linear ablation rate of C/SiC-SiHfBCN composites was more than an order of magnitude lower than that of other reported C/SiC composites, indicating an enhanced ablation resistance of the C/SiC-SiHfBCN composites.

Development of high-temperature wave-transparent nitride-based CFCMCs for aircraft radomes

Abstract: Taking into account the requirements for structural–functional integration, the main developments in high-temperature wave-transparent materials for supersonic/hypersonic aircraft radomes are summarized. Nitride-based continuous fiber-reinforced ceramic matrix composites (CFCMCs) have been studied in terms of preparation and properties of the four structural units, i.e. reinforcing fibers, interphase, matrix, and surface coating based on nitride system. Precise control of preparation process of each structural unit is crucial, which determines its composition, structure and properties, and strategy for structural design of composites. As the main load-bearing unit, fibers play a critical role in the properties of composites and it is paramount to obtain high-performance fibers, which depends on the composition and structure of the fibers. In addition, control of interfacial bonding and the modulus matching relationship between the fibers and matrix is the key to ensure that the fiber exerts its strengthening and toughening effects.

SiC-Based Composite Material Reinforced with Molybdenum Wire

Abstract: Silicon carbide (SiC) possesses a unique combination of properties such as high mechanical strength at elevated temperatures, wear resistance, low thermal expansion coefficient, high temperature oxidation resistance, corrosion stability, radiation hardness, high chemical inertness, and thermal conductivity. Unfortunately, SiC is very brittle and cannot, therefore, be used “as is”. SiC’s crack resistance, due to the prevention of crack propagation, can be increased by the reinforcing of SiC. In this paper, a novel method for manufacturing SiC-based composites reinforced with Mo wire is developed. The composites are produced by infiltrating porous carbon blanks with molten silicon. The molten silicon reacts with the molybdenum wire embedded in the carbon blanks. As a result, a complex interfacial silicide layer with a predominant MoSi2 phase is formed on the surface of the Mo wire. In addition, a thin layer of Mo5Si3 is formed between the residual metal in the core of the wire and the disilicide. A stable bond of the interfacial layer with both the residual metal and the SiC-based ceramic matrix is observed. Mechanical tests on the obtained samples for three-point bending at 20 and 1500 °C showed quasi-plastic damage. The reinforcing elements act as stoppers for propagating cracks in the event of a matrix failure. The developed method for producing composites with a ceramic matrix reinforced with metal wire makes it possible to reduce the cost of machining and manufacturing products with complex geometric shapes. It also opens the way for broader applications of SiC-based composites.

Applications of Ceramic Matrix Composites in Liquid Rocket Propulsion

Abstract: In this paper, the applications of ceramic matrix composites (CMCs) in liquid rocket engines (LRE) are investigated from the perspective of several years’ experience with volume production of hot-section CMC components for air-breathing gas turbine engines. SiC/SiC CMC applications are proposed that offer the best advantages, and immediate developments needed to facilitate the application of CMCs in LREs are identified. The technology readiness, characteristics, advantages, and disadvantages of CMCs in liquid rocket engines are discussed. A performance model of a generic gas generator cycle rocket engine indicates that engine Isp could increase by up to 5.5 seconds if the turbine inlet temperature could be raised to 2,200 K, a capability that may be enabled with CMCs. For a typical mission consisting of a 5-minute burn operating at 890 kN thrust, this results in a reduction of consumed propellant of 2,040 kg. A separate thermostructural analytical study was conducted using a representative regenerative cooling channel made of CMC subject to realistic environments. Results indicate that CMCs may outperform traditional materials given the expected range of conditions, particularly over repeated cycles, and at significantly lower weight.

Investigation of the Resistance to High-Speed Impact Loads of a Heterogeneous Materials Reinforced with Silicon Carbide Fibers and Powder

Abstract: Pioneering studies on the additive manufacturing of a cermet heterogeneous material using SiC ceramic fiber were carried out. Unique studies of the damage staging (cratering) and the transition to the destruction of the formed material during high-speed impact created with the help of an electrodynamic mass accelerator have been carried out. It has been shown that the use of ceramic fiber in a metal matrix reduces the impact crater depth by 22% compared to material with ceramic particles. For the first time, the phase composition of the resulting composite was studied using synchrotron radiation. It was shown that, as a result of laser exposure, silicon carbide SiC is dissolved in the titanium matrix with the formation of secondary compounds of the TiC and Ti5Si3C types. It has been established that the use of SiC ceramic fibers leads to their better dissolution, in contrast to the use of SiC ceramic particles, with the formation of secondary phase compounds, and to an increase in mechanical characteristics.

Online Prediction of Grinding Wheel Condition and Surface Roughness for the Fused Silica Ceramic Composite Material Based on the Monitored Power Signal

Abstract: The fused silica ceramic matrix composite (SiO2f/SiO2) is characterized as one of the most promising materials in radar radomes and wave-transparent antenna windows. However, the ceramic matrix surface is rather rough, which reduces their service life in severe environments. Although precision grinding is used to improve surface quality, it gets difficult to precisely achieve the desired surface requirement due to the SiO2f/SiO2 material hardness, brittleness, and complicated fiber structure, as well as the uncertain wheel conditions. Especially the wheel condition and its influence on surface quality are unable to quantify directly. With the fast development of IoT monitoring and cyber-physical system, online prediction using process physics signals gains more interest. Power monitoring is a convenient way to obtain valuable grinding information at a relatively lower cost, making it more popular in the industry. However, the links between grinding parameters, power signal, and wheel conditions, surface quality is unclear. A series of grinding experiments of the SiO2f/SiO2 workpiece has been designed to demonstrate how the wheel conditions are indicated using the warm-cold density chart of specific grinding energy. A novel exponential polynomial model of surface roughness associated with wheel conditions indicated by the cutting power signal has been built. Compared with the conventional prediction model, REs center, MSE, and Pearson correlation coefficient are improved significantly from −0.0213, 0.029669, and 0.8695 to 0.0022, 0.022478, and 0.8710, respectively.

Quasistatic Compression Properties of Fiber Hybrid Ceramic Matrix Composites with Different Hybrid Ratios and Fiber Dispersions

Abstract: Fiber hybrid composites can give full play to the performance advantages of different component fibers, and hybrid weaving is one of the effective methods to improve the properties of composite materials. Herein, based on the flexible‐oriented 3D woven technology, fiber hybrid ceramic matrix composites (FHCMCs) with different hybrid ratios and fiber dispersions are designed and fabricated, and their quasistatic compression properties, failure modes, and hybrid effects are studied. The results show that the reasonable hybrid of carbon (C) fiber and silicon carbide (SiC) fiber can make up for the shortcoming of single‐fiber composites and improve the compression properties of FH‐CMCs. The compressive failure modes of the FH‐CMCs are mainly the crushing failure in the C fiber layers and shear failure of the specimen. For the compressive failure deformation, the positive hybrid effect gradually becomes obvious with the increase of fiber dispersion, but the compressive strength shows a negative hybrid effect as a whole. The improved rule of mixture by introducing different parameters has a better prediction effect for the compressive strength of the FH‐CMCs. The research results provide experimental and theoretical reference for the high‐performance manufacturing of hybrid composites in the future.

Introduction

Abstract: In this chapter, the application background of ceramic-matrix composites is introduced. Stress-rupture behavior of the SiC/SiC composite at elevated temperatures is analyzed. Multiple damage mechanisms models of interphase oxidation, matrix cracking, interface debonding, and fibers failure are adopted in the analysis for stress-rupture. The effect of temperature on the stress-rupture behavior of the SiC/SiC composite is also analyzed.

Design, Manufacturing, and Characterization of a Novel Ceramic Matrix Composite

Abstract: A novel ceramic matrix composite (CMC) system consisting of a commercially available SiC fibre, variations of electrophoretically deposited (EPD) fibre-matrix interphases, and a liquid metal melt infiltrated matrix was designed and characterised. A factorial design of experiments approach was undertaken to evaluate the deposition variables which would result in a functioning fibre-matrix interphase. A 25-2 partial factorial design matrix was selected with factors: electric potential, deposition time, surfactant, binder, and solids loading. The design matrix was replicated for four different EPD fibre-matrix interphase coating combinations: Al2O3/SiC, BN/PSZ, ZrC/ZTA, and SiC/Si3N4/SiC. Microcomposites were evaluated for tensile properties using a standard displacement controlled tensile test program. Microcomposites were tested at room temperature immediately following fabrication and following exposure to a standard atmosphere at 1000 °C for 1 h. Samples with ZrC/ZTA and SiC/Si3N4/SiC coatings demonstrated the best tensile properties in room temperature tests while samples with BN/PSZ and SiC/Si3N4/SiC coatings demonstrated the best retention of tensile properties following high temperature exposure. Subsequent SEM analysis revealed that coatings with smaller particle diameters as the inner layer of the fibre-matrix interphase coating produced more uniform coatings and the less fibre degradation due to oxidation following high temperature exposure. Additional microcomposites were fabricated for high temperature tensile testing; however, these samples were unable to bear recordable loads, an SEM examination revealed significant degradation of the matrix phase beneath the high temperature adhesive. Optical microscopy was used to evaluate coating thicknesses of coated fibre bundles prior to heat treatments. Measured coating thickness indicated that generally higher deposition times resulted in thicker coatings; however, coatings produced using 25 V electric potential were thicker than coatings produced using 12.5 V and 50 V electric potentials. This is likely due to a greater deposition efficiency factor at 25 V. FEA analysis was used to evaluate the electrical properties of an idealized version of the stationary EPD cell. This analysis showed a significant variation in the electric field along the fibre axis as well as a significant variation in electrical field between fibres in the centre of the fibre bundle and on the outer edge of the fibre bundle.

Thermal and Mechanical Properties of Plain Woven Ceramic Matrix Composites by the Imaged-Based Mesoscopic Model

Abstract: The mesoscopic finite element model of ceramic matrix composites is developed by reconstructing computed tomography images. The relationship between microstructure and macroscopic properties and their dispersion are explored. Firstly, a three-dimensional reconstructed computed tomography model was carried out to calculate the orientation of the components. Secondly, the orientation and gray value of images were used to identify the basic structure of composites including fiber tows, matrix, and porosities. Finally, the two-dimensional finite element model was developed to analyze the macroscopic thermal and mechanical properties. The numerical results showed that: (1) the geometries and distributions of pores had a significant effect on the through-thickness modulus and thermal conductivity; (2) the stress and heat flow concentration area on the material surface usually occurred in narrow gaps between closely spaced longitudinal tows; (3) the elastic modulus and thermal conductivity were dispersive, and their distribution followed by two-parameter Weibull distribution.

3D printed silicon nitride, alumina, and hydroxyapatite ceramic reinforced Ti6Al4V composites - Tailored microstructures to enhance bio-tribo-corrosion and antibacterial properties.

Abstract: This study utilized directed energy deposition (DED) as a metal additive manufacturing (AM) technique to create ceramic-reinforced composites of Ti6Al4V (Ti64) with hydroxyapatite (HA), alumina (Al2O3), and silicon nitride (Si3N4). The resulting composites had tailored microstructures designed to improve bio-tribological and antibacterial properties simultaneously. A total of 5-wt % ceramic reinforcement were used in Ti64 in four different composites - (1) only Si3N4 (5S), (2) only Al2O3 (5A), (3) 3 wt % Si3N4 and 2 wt% HA (32SH) and (4) 3 wt % Al2O3 and 2 wt% HA (32AH). Microstructural observations revealed that martensite transformation between α and β-Ti in composites resulted in compressive residual stress at the matrix. Coherency is observed between the ceramic particles and Ti64 matrix, preventing cracking, debonding, or porosity. Vicker's hardness of the composite samples increases by 50% over the Ti64 matrix. Various strengthening mechanisms are discussed in detail, representing the reason behind the reduction of compound wear in 5S and 5A composites. Si3N4-added composites demonstrated an antibacterial response against gram-positive Staphylococcus aureus. The multifunctional performance of ceramic-reinforced Ti64 composites makes them suitable for articulating biomedical devices such as femoral heads in hip implants.

Preparation and properties of highly thermal conductive C/C-SiC

Abstract: A kind of highly thermal conductive silicon carbide matrix composites (c-1000/C-SiC, c-600/C-SiC) reinforced with chopped mesophase pitch-based carbon fibers (c-MPCF) including 1000 W/(m·K) and 600 W/(m·K) were successfully prepared by the phenolic resin precursor impregnation pyrolysis and liquid silicon infiltration (LSI) method. Quasi-isotropic c-MPCF/C-SiC composites demonstrate excellent thermophysical properties, including average flexure strength of 111.5 MPa of c-1000/C-SiC and 123.0 MPa of c-600/C-SiC, average high thermal conductivity of 101.33 W/(m·K) and 93.94 W/(m·K) at room temperature, low coefficient of thermal expansions of 2.942 ppm/K and 3.147 ppm/K at room temperature, which provides a new strategy for preparing isotropic silicon carbide ceramic matrix composites with comprehensive properties and dimensional stability.

Extremely low thermal conductivity and high electrical conductivity of sustainable carbonceramic electrospun nonwoven materials

Abstract: Materials with an extremely low thermal and high electrical conductivity that are easy to process, foldable, and nonflammable are required for sustainable applications, notably in energy converters, miniaturized electronics, and high-temperature fuel cells. Given the inherent correlation between high thermal and high electrical conductivity, innovative design concepts that decouple phonon and electron transport are necessary. We achieved this unique combination of thermal conductivity 19.8 ± 7.8 mW/m/K (cross-plane) and 31.8 ± 11.8 mW/m/K (in-plane); electrical conductivity 4.2 S/cm in-plane in electrospun nonwovens comprising carbon as the matrix and silicon-based ceramics as nano-sized inclusions with a sea-island nanostructure. The carbon phase modulates electronic transport for high electrical conductivity, and the ceramic phase induces phonon scattering for low thermal conductivity by excessive boundary scattering. Our strategy can be used to fabricate the unique nonwoven materials for real-world applications and will inspire the design of materials made from carbon and ceramic.