Subjects -> MANUFACTURING AND TECHNOLOGY (Total: 363 journals)
    - CERAMICS, GLASS AND POTTERY (31 journals)
    - MACHINERY (34 journals)
    - PACKAGING (19 journals)
    - PLASTICS (42 journals)
    - RUBBER (4 journals)


Showing 1 - 29 of 29 Journals sorted alphabetically
Advances in Applied Ceramics     Hybrid Journal   (Followers: 4)
Boletín de la Sociedad Española de Cerámica y Vidrio     Open Access   (Followers: 1)
Ceramics     Open Access  
Ceramics International     Hybrid Journal   (Followers: 26)
CeROArt     Open Access   (Followers: 1)
Challenging Glass Conference Proceedings     Open Access   (Followers: 1)
Crystal Growth & Design     Hybrid Journal   (Followers: 13)
Glass and Ceramics     Hybrid Journal   (Followers: 3)
Glass Technology - European Journal of Glass Science and Technology Part A     Full-text available via subscription   (Followers: 1)
International Journal of Applied Glass Science     Hybrid Journal   (Followers: 2)
International Journal of Ceramic Engineering & Science     Open Access  
Journal of Advanced Ceramics     Open Access   (Followers: 9)
Journal of Asian Ceramic Societies     Open Access  
Journal of Ceramics     Open Access   (Followers: 3)
Journal of Non-Crystalline Solids     Hybrid Journal   (Followers: 7)
Journal of Non-Crystalline Solids : X     Open Access  
Journal of the American Ceramic Society     Hybrid Journal   (Followers: 24)
Journal of the Australian Ceramic Society     Hybrid Journal  
Journal of The Chinese Ceramic Society     Open Access  
Journal of the European Ceramic Society     Hybrid Journal   (Followers: 16)
Journal of the Korean Ceramic Society : 한국세라믹학회지     Hybrid Journal  
Liquid Crystals Today     Hybrid Journal   (Followers: 1)
Molecular Crystals and Liquid Crystals     Hybrid Journal   (Followers: 1)
New Journal of Glass and Ceramics     Open Access   (Followers: 6)
Old Potter's Almanack     Open Access  
Open Ceramics     Open Access  
Powder Metallurgy and Metal Ceramics     Hybrid Journal   (Followers: 7)
Progress in Crystal Growth and Characterization of Materials     Full-text available via subscription   (Followers: 8)
Transactions of the Indian Ceramic Society     Partially Free   (Followers: 1)
Similar Journals
Journal Cover
Journal of Advanced Ceramics
Journal Prestige (SJR): 0.365
Citation Impact (citeScore): 1
Number of Followers: 9  

  This is an Open Access Journal Open Access journal
ISSN (Print) 2226-4108 - ISSN (Online) 2227-8508
Published by SpringerOpen Homepage  [228 journals]
  • Erratum to: Si-based polymer-derived ceramics for energy conversion and

    • Abstract: Besides the original acknowledgements, the authors Ralf Riedel and Magdalena Graczyk-Zajac would like to also acknowledge EU support in the frame of H2020 project SIMBA under grant agreement number 963542.
      PubDate: 2022-06-01
  • Modification of YSZ fiber composites by Al2TiO5 fibers for high thermal
           shock resistance

    • Abstract: Yttria-stabilized zirconia (YSZ) fiber composites are highly efficient thermal insulating materials; however, the poor thermal shock resistance limits their versatile applications. In the present study, YSZ fiber was mixed directly with Al2TiO5 fiber, which had an extremely low thermal expansion coefficient, to prepare YSZ−Al2TiO5 (ZAT) fiber composites by compression molding and heat treatment. The minimum thermal expansion coefficient of the prepared ZAT fiber composites was measured to be 7.74×10−6 K−1, which was 26% lower than that of the YSZ fiber composites (10.42×10−6 K−1). It was shown that the prepared ZAT fiber composites maintain the integrity after undergoing 51 thermal shock cycles between 1100 °C and room temperature. Whereas, YSZ fiber composites burst immediately after only one thermal shock cycle under the same condition. In addition, the ZAT fiber composites also exhibit considerable mechanical and thermal insulating performance.
      PubDate: 2022-06-01
  • Advanced inorganic/polymer hybrid electrolytes for all-solid-state lithium

    • Abstract: Solid-state batteries have become a frontrunner in humankind’s pursuit of safe and stable energy storage systems with high energy and power density. Electrolyte materials, currently, seem to be the Achilles’ heel of solid-state batteries due to the slow kinetics and poor interfacial wetting. Combining the merits of solid inorganic electrolytes (SIEs) and solid polymer electrolytes (SPEs), inorganic/polymer hybrid electrolytes (IPHEs) integrate improved ionic conductivity, great interfacial compatibility, wide electrochemical stability window, and high mechanical toughness and flexibility in one material, having become a sought-after pathway to high-performance all-solid-state lithium batteries. Herein, we present a comprehensive overview of recent progress in IPHEs, including the awareness of ion migration fundamentals, advanced architectural design for better electrochemical performance, and a perspective on unconquered challenges and potential research directions. This review is expected to provide a guidance for designing IPHEs for next-generation lithium batteries, with special emphasis on developing high-voltage-tolerance polymer electrolytes to enable higher energy density and three-dimensional (3D) continuous ion transport highways to achieve faster charging and discharging.
      PubDate: 2022-05-13
  • Sintering behavior of alumina whisker reinforced zirconia ceramics in hot
           oscillatory pressing

    • Abstract: Alumina whisker reinforced zirconia ceramic composite was prepared by both hot oscillatory pressing (HOP) and conventional hot pressing (HP). The results show that compared with HP, HOP can significantly increase the final density and densification rate of the material. Analysis of densification kinetics reveals that the predominant densification mechanism transits from grain boundary sliding in the beginning to the diffusion in the later stage. The main effect of the oscillating pressure is to increase the densification rate in the process of grain boundary sliding. The current study suggests that HOP is a promising technique for densifying whisker reinforced ceramics.
      PubDate: 2022-05-13
  • Effects of pellet surface roughness and pre-oxidation temperature on CMAS
           corrosion behavior of Ti2AlC

    • Abstract: Calcium-magnesium-alumina-silicate (CMAS) corrosion is a serious threat to thermal barrier coatings (TBCs). Ti2AlC has been proven to be a potential protection layer material for TBCs to resist CMAS corrosion. In this study, the effects of the pellet surface roughness and temperature on the microstructure of the pre-oxidation layer and CMAS corrosion behavior of Ti2AlC were investigated. The results revealed that pre-oxidation produced inner Al2O3 layer and outer TiO2 clusters on the pellet surfaces. The content of TiO2 decreased with decreasing pellet surface roughness and increased along with the pre-oxidation temperature. The thickness of Al2O3 layer is also positively related to the pre-oxidation temperature. The Ti2AlC pellets pre-oxidized at 1050 °C could effectively resist CMAS corrosion by promoting the crystallization of anorthite (CaAl2Si2O8) from the CMAS melt rapidly, and the resistance effectiveness increased with the pellet surface roughness. Additionally, the CMAS layer mainly spalled off at the interface of CaAl2Si2O8/Al2O3 layer after thermal cycling tests coupled with CMAS corrosion. The Al2O3 layer grown on the rough interface could combine with the pellets tightly during thermal cycling tests, which was attributed to obstruction of the rough interface to crack propagation.
      PubDate: 2022-05-11
  • High transparency Pr:Y2O3 ceramics: A promising gain medium for red
           emission solid-state lasers

    • Abstract: Highly transparent 0.5 and 1.0 at% Pr-doped Y2O3 ceramics were fabricated by vacuum sintering plus hot isostatic pressing (HIP) treatment. The selection of suitable pre-sintering temperatures and right microstructures before HIP was critical to obtain high density of the final sintered bodies. The well-densified ceramics had pore-free microstructures with an average grain size of about 1 µm. It was also found that the charge states of the Pr ions could be changed through regulating the annealing atmospheres, resulting in different absorption and emission characteristics in the visible wavelength region. Annealing in reducing atmosphere (5% H2/95% Ar) favored the formation of Pr3+, resulting in stronger red emissions, while annealing in oxygen atmosphere led to the rise of lattice constant due to the concentration increase of oxygen interstitials. The H2/Ar-annealed 0.5 at% Pr:Y2O3 ceramics exhibited strong red emission at 600–675 nm, which may be a promising gain material for red solid-state lasers.
      PubDate: 2022-05-11
  • Optical, thermal, and mechanical properties of (Y1−xScx)2O3
           transparent ceramics

    • Abstract: Sesquioxides such as Y2O3 and Sc2O3 are important optical materials, but the fabrication of their transparent ceramics remains a challenge due to the ultra-high melting point of over 2400 °C. In this work, a series of (Y1−xScx)2O3 transparent ceramics were successfully fabricated by a simple vacuum sintering process without any sintering additives, and the effect of scandium (Sc) content (x) on the crystal structure and optical/thermal/mechanical properties was evaluated. Y2O3 and Sc2O3 form a complete solid solution with a cubic bixbyite structure. The formation of (Y1−xScx)2O3 solid solution promotes the densification of ceramics, leading to the realization of high transparency close to the theoretical transmittance over a wide wavelength range of 0.35–8 µm. In particular, the in-line transmittance in the range of 0.6–6 µm remains above 80% for (Y1−xScx)2O3 with x = 0.23–0.31, while the pristine Y2O3 and Sc2O3 are opaque. Moreover, the mechanical properties including Vickers hardness (HV), fracture toughness (KIC), and biaxial flexural strength (δb) are evidently enhanced due to the solid solution strengthening, while the thermal conductivity (k) is reduced due to the reduction of photon free path. This study demonstrates that forming of solid solution is a facile and universal approach for preparing sesquioxide transparent ceramics with high optical and mechanical quality.
      PubDate: 2022-05-11
  • High-entropy rare-earth zirconate ceramics with low thermal conductivity
           for advanced thermal-barrier coatings

    • Abstract: The high-entropy rare-earth zirconate ((La0.2Nd0.2Sm0.2Gd0.2Yb0.2)2Zr2O7, 5RE2Zr2O7 HEREZs) ceramics were successfully prepared by a new high-speed positive grinding strategy combined with solid-state reaction method. The microstructure, crystal structure, phase composition, and thermophysical and mechanical properties of the samples were systematically investigated through various methods. Results indicate that the samples have a single-phase defect fluorite-type crystal structure with excellent high-temperature thermal stability. The as-prepared samples also demonstrate low thermal conductivity (0.9–1.72 W·m−1·K−1 at 273–1273 K) and high coefficient of thermal expansion (CTE, 10.9 × 10−6 K−1 at 1273 K), as well as outstanding mechanical properties including large Young’s modulus (E = 186–257 GPa) and high fracture toughness (KIC). Furthermore, the formation possibility of the as-prepared samples was verified through the first-principles calculations, which suggested the feasibility to form the 5RE2Zr2O7 HE-REZs in the thermodynamic direction. Therefore, in view of the excellent multifunctional properties exhibited by the as-prepared 5RE2Zr2O7 HE-REZs, they have great potential applications in next-generation thermal-barrier coatings (TBCs).
      PubDate: 2022-05-11
  • Self-ball milling strategy to construct high-entropy oxide coated
           LiNi0.8Co0.1Mn0.1O2 with enhanced electrochemical performance

    • Abstract: High-entropy oxides (HEOs) are a new class of emerging materials with fascinating properties (such as structural stability, tensile strength, and corrosion resistance). High-entropy oxide coated Ni-rich cathode materials have great potential to improve the electrochemical performance. Here, we present a facile self-ball milling method to obtain (La0.2Nd0.2Sm0.2Eu0.2Gd0.2)2Zr2O7 (HEO) coated LiNi0.8Co0.1Mn0.1O2 (NCM811). The HEO coating endows NCM811 with a stable surface, reduces the contact with the external environment (air and electrolyte), and inhibits side reactions between cathode and electrolyte. These favorable effects, especially when the coating amount is 5 wt%, result in a significant reduction of the battery polarization and an increase in the capacity retention from 57.3% (NCM811) to 74.2% (5HEO-NCM811) after 300 cycles at 1 C (1 C = 200 mA·h·g−1). Moreover, the morphology and spectroscopy analysis after the cycles confirmed the inhibitory effect of the HEO coating on electrolyte decomposition, which is important for the cycle life. Surprisingly, HEO coating reduces the viscosity of slurry by 37%–38% and significantly improves the flowability of the slurry with high solid content. This strategy confirms the feasibility of HEO-modified Ni-rich cathode materials and provides a new idea for the design of high-performance cathode materials for Li-ion batteries.
      PubDate: 2022-05-11
  • Patterned glass ceramic design for high-brightness high-color-quality
           laser-driven lightings

    • Abstract: Up-to-date laser-driven lightings confront a challenge of simultaneously achieving good photometric and chromatic performances. Herein, the coupling of “patterned package design” and “phosphor wheel” was proposed and demonstrated effectively to deal with this tough issue, based on a new architecture of CaAlSiN3:Eu2+ (CASN:Eu) glass ceramic film (GCF) on Y3Al5O12:Ce3+ (YAG:Ce) GC plate. The fabricated composite has no interface between the two functional layers and retains the admirable luminescent features from CASN:Eu and YAG:Ce for the microstructural integrity during co-sintering. The studies on laser-microcrystalline interactions reveal that the luminescence saturation is almost determined by thermal quenching for YAG:Ce, but is ascribed to thermal/intensity quenching which are equally crucial for CASN:Eu. Benefiting from the elaborate architecture design, good color chromaticity tunability was obtained, and severe photon reabsorption was reduced. Moreover, accompanied with the rotation induced increase of thermal convection to air and pulse-like excitation, the constructed lighting engine under blue laser driven shows bright white light with luminous flux (LF) higher than 1000 lm, adjustable chromaticity from cool to warm, and improved color rendering index (CRI) approaching to 70.
      PubDate: 2022-05-11
  • Synergistic effect of V2O5 and Bi2O3 on the grain boundary structure of
           high-frequency NiCuZn ferrite ceramics

    • Abstract: High-frequency soft magnetic ferrite ceramics are desired in miniaturized and efficient power electronics but remain extremely challenging to deploy on account of the power loss (Pcv) at megahertz frequencies. Here, we prepared NiCuZn ferrite with superior high-frequency properties by V2O5 and Bi2O3 synergistic doping, which proves to be a potent pathway to reduce Pcv of the ferrite at megahertz frequencies. The sample doped with 800 ppm V2O5 and 800 ppm Bi2O3 yielded the most optimized magnetic properties with a Pcv of 113 kW/m3 (10 MHz, 5 mT, 25 °C), an initial permeability (μi) of 89, and a saturation induction (Bs) of 340 mT, which is at the forefront of the reported results. These outstanding properties are closely related to the notable grain boundary structure, which features a new type of nano-Bi2Fe4O9 phase around ferrite grains and a Ca/Si/V/O amorphous layer. Our results indicate great strides in correlating the grain boundary structure with multiple-ion doping and set the scene for the developing high-frequency soft magnet ferrites.
      PubDate: 2022-05-11
  • Sunlight activated ultra-stable long persistent luminescence glass ceramic
           for outdoor information display

    • Abstract: Abstract Natural sunlight activated persistent luminescence (PeL) is ideal candidate for optical information display in outdoors without the requirement of electric supply. Except the brightness and duration, the stability especially water resistance of the PeL materials is of significant importance for practical application, which remains a great obstacle up to date. Herein, we report a new sunlight activated PeL glass ceramic containing hexagonal Sr13Al22Si10O66:Eu2+ crystals, which exhibits strong blue PeL and can last more than 200 h. The PeL can be charged by the full wavelengths located in AM 1.5G due to the broad distribution of traps in the crystal structure. The PeL is clearly observed by the naked eye even after 24 h upon sunlight irradiation irrespective of the weather, and the photoluminescence intensity only decreased ∼3.3% after storing in water for 365 d. We demonstrate its potential application for thermal and stress responsive display as well as long-term continuous security indication upon sunlight irradiation, which not only save vast energy and reduce environment pollution, but also are appropriate for outdoor usage.
      PubDate: 2022-05-04
  • Al-modification for PS-PVD 7YSZ TBCs to improve particle erosion and
           thermal cycle performances

    • Abstract: Abstract Plasma spray-physical vapor deposition (PS-PVD) as a novel process was used to prepare feather-like columnar thermal barrier coatings (TBCs). This special microstructure shows good strain tolerance and non-line-of-sight (NLOS) deposition, giving great potential application in aero-engine. However, due to serious service environment of aero-engine, particle erosion performance is a weakness for PS-PVD 7YSZ TBCs. As a solution, an Al-modification approach was proposed in this investigation. Through in-situ reaction of Al and ZrO2, an α-Al2O3 overlay can be formed on the surface of 7YSZ columnar coating. The results demonstrate that this approach can improve particle erosion resistance since hardness improvement of Al-modified TBCs. Meanwhile, as another important performance of thermal cycle, it has a better optimization with 350-cycle water-quenching, compared with the as-sprayed TBCs.
      PubDate: 2022-05-04
  • Optimizing energy harvesting performance by tailoring
           ferroelectric/relaxor behavior in KNN-based piezoceramics

    • Abstract: Abstract Piezoelectric energy harvesters (PEHs) fabricated using piezoceramics could convert directly the mechanical vibration energy in the environment into electrical energy. The high piezoelectric charge coefficient (d33) and large piezoelectric voltage coefficient (g33) are key factors for the high-performance PEHs. However, high d33 and large g33 are difficult to simultaneously achieve with respect to g33 = d33/(ε0εr) and d33 = 2Qε0εrPr. Herein, the energy harvesting performance is optimized by tailoring the CaZrO3 content in (0.964−x)(K0.52Na0.48)(Nb0.96Sb0.04)O3 −0.036(Bi0.5Na0.5)ZrO3−xCaZrO3 ceramics. First, the doping CaZrO3 could enhance the dielectric relaxation due to the compositional fluctuation and structural disordering, and thus reduce the domain size to ∼30 nm for x = 0.006 sample. The nanodomains switch easily to external electric field, resulting in large polarization. Second, the rhombohedral–orthorhombic–tetragonal phases coexist in x = 0.006 sample, which reduces the polarization anisotropy and thus improves the piezoelectric properties. The multiphase coexistence structures and miniaturized domains contribute to the excellent piezoelectric properties of d33 (354 pC/N). Furthermore, the dielectric relative permittivity (εr) reduces monotonously as the CaZrO3 content increases due to the relatively low ion polarizability of Ca2+ and Zr4+. As a result, the optimized energy conversion coefficient (d33 × g33, 5508 × 10−15 m2/N) is achieved for x = 0.006 sample. Most importantly, the assembled PEH with the optimal specimen shows the excellent output power (∼48 µW) and lights up 45 red commercial light-emitting diodes (LEDs). This work demonstrates that tailoring ferroelectric/relaxor behavior in (K,Na)NbO3-based piezoelectric ceramics could effectively enhance the electrical output of PEHs.
      PubDate: 2022-05-04
  • A high-entropy spinel ceramic oxide as the cathode for proton-conducting
           solid oxide fuel cells

    • Abstract: Abstract A high-entropy ceramic oxide is used as the cathode for the first time for proton-conducting solid oxide fuel cells (H-SOFCs). The Fe0.6Mn0.6Co0.6Ni0.6Cr0.6O4 (FMCNC) high-entropy spinel oxide has been successfully prepared, and the in situ chemical stability test demonstrates that the FMCNC material has good stability against CO2. The first-principles calculation indicates that the high-entropy structure enhances the properties of the FMCNC material that surpasses their individual components, leading to lower O2 adsorption energy for FMCNC than that for the individual components. The H-SOFC using the FMCNC cathode reaches an encouraging peak power density (PPD) of 1052 mW·cm−2 at 700 °C, which is higher than those of the H-SOFCs reported recently. Additional comparison was made between the high-entropy FMCNC cathode and the traditional Mn1.6Cu1.4O4 (MCO) spinel cathode without the high-entropy structure, revealing that the formation of the high-entropy material allows the enhanced protonation ability as well as the movement of the O p-band center closer to the Fermi level, thus improving the cathode catalytic activity. As a result, the high-entropy FMCNC has a much-decreased polarization resistance of 0.057 Ω·cm2 at 700 °C, which is half of that for the traditional MCO spinel cathode without the high-entropy design. The excellent performance of the FMCNC cell indicates that the high-entropy design makes a new life for the spinel oxide as the cathode for H-SOFCs, offering a novel and promising route for the development of high-performance materials for H-SOFCs.
      PubDate: 2022-05-01
  • High-entropy spinel ferrites MFe2O4 (M = Mg, Mn, Fe, Co, Ni, Cu, Zn) with
           tunable electromagnetic properties and strong microwave absorption

    • Abstract: Abstract Ferrites are the most widely used microwave absorbing materials to deal with the threat of electromagnetic (EM) pollution. However, the lack of sufficient dielectric loss capacity is the main challenge that limits their applications. To cope with this challenge, three high-entropy (HE) spinel-type ferrite ceramics including (Mg0.2Mn0.2Fe0.2Co0.2Ni0.2)Fe2O4, (Mg0.2Fe0.2Co0.2Ni0.2Cu0.2)Fe2O4, and (Mg0.2Fe0.2Co0.2Ni0.2Zn0.2)Fe2O4 were designed and successfully prepared through solid state synthesis. The results show that all three HE MFe2O4 samples exhibit synergetic dielectric loss and magnetic loss. The good magnetic loss ability is due to the presence of magnetic components; while the enhanced dielectric properties are attributed to nano-domain, hopping mechanism of resonance effect and HE effect. Among three HE spinels, (Mg0.2Mn0.2Fe0.2Co0.2Ni0.2)Fe2O4 shows the best EM wave absorption performance, e.g., its minimum reflection loss (RLmin) reaches −35.10 dB at 6.78 GHz with a thickness of 3.5 mm, and the optimized effective absorption bandwidth (EAB) is 7.48 GHz from 8.48 to 15.96 GHz at the thickness of 2.4 mm. Due to the easy preparation and strong EM dissipation ability, HE MFe2O4 are promising as a new type of EM absorption materials.
      PubDate: 2022-05-01
  • Interior-collapsing mechanism by hydrothermal process of the MgAl2O4/MgO
           porous ceramic

    • Abstract: Abstract Ceramic core is a critical component in the super-alloy turbine blade casting. In our previous work, a novel multi-phase MgAl2O4/MgO porous ceramic was prepared for this purpose. The most important property was that it crumbled completely after hydrothermal treatment in just pure water, due to the hydration of MgO. In this work, the hydration process of the MgO embedded in the inert matrix was investigated in detail. The collapse behaved as an interior destruction without any bulk expansion of the sample. The hydration percentage was the only factor related to the water-collapsibility. The morphology of hydration product indicated that the reaction advanced in particular direction. Based on the finite element analysis for the expansion effect on the porous structure, the interior-collapsing mechanism was proposed. During the hydration process, the MgO grains exerted pressure to the surrounding matrix and induced the collapse in the adjacent structure. This process took place throughout the matrix. Finally, the sample crumbled completely to the powders. No bulk dilatation was detected before the powdering, indicating that the collapse process would not exert pressure outward. Thus the alloy blade would not be damaged during the removal of the ceramic core. It was also predicted that the decrease in the MgO grain size was beneficial to the water-collapsibility.
      PubDate: 2022-05-01
  • Cs3Bi2I9-hydroxyapatite composite waste forms for cesium and iodine

    • Abstract: Abstract Perovskite-based ceramic composites were developed as potential waste form materials for immobilizing cesium (Cs) and iodine (I) with high waste loadings and chemical durability. The perovskite Cs3Bi2I9 has high Cs (22 wt%) and I (58 wt%) content, and thus can be used as a potential host phase to immobilize these critical radionuclides. In this work, the perovskite Cs3Bi2I9 phase was synthesized by a cost effective solution-based approach, and was embedded into a highly durable hydroxyapatite matrix by spark plasma sintering to form dense ceramic composite waste forms. The chemical durabilities of the monolithic Cs3Bi2I9 and Cs3Bi2I9—hydroxyapatite composite pellets were investigated by static and semi-dynamic leaching tests, respectively. Cs and I are incongruently released from the matrix for both pure Cs3Bi2I9 and composite structures. The normalized Cs release rate is faster than that of I, which can be explained by the difference in the strengths between Cs-I and Bi-I bonds as well as the formation of insoluble micrometer-sized BiOI precipitates. The activation energies of elemental releases based on dissolution and diffusion-controlled mechanisms are determined with significantly higher energy barriers for dissolution from the composite versus that of the monolithic Cs3Bi2I9. The ceramic-based composite waste forms exhibit excellent chemical durabilities and waste loadings, commensurate with the state-of-the-art glass-bonded perovskite composites for I and Cs immobilization.
      PubDate: 2022-04-02
  • Fabrication and properties of non-stoichiometric Tb2(Hf1−xTbx)2O7−x
           magneto-optical ceramics

    • Abstract: Abstract Non-stoichiometric Tb2(Hf1−xTbx)2O7−x (x = −0.07–0.45) magneto-optical ceramics were fabricated by solid-state reactive sintering in vacuum combined with hot isostatic pressing (HIP) post-treatment without any sintering aids. The phase composition, densification process, microstructure, optical transmittance, and Verdet constant of Tb2(Hf1−xTbx)2O7−x ceramics were investigated. The in-line transmittance of (Tb0.93Hf0.07)2Hf2O7.07 ceramics with a thickness of 2.0 mm reaches 74.6% at 1064 nm. The Verdet constant of Tb2(Hf1−xTbx)2O7−x ceramics is −153.4, −155.8, and −181.2 rad/(T·m) at the wavelength of 633 nm when x = −0.07, 0, and 0.1, respectively. The Verdet constant increases with the increase of Tb content, and these values are higher than that of the commercial Tb3Ga5O12 crystal, indicating that non-stoichiometric Tb2(Hf1−xTbx)2O7−x ceramics have a great potential for the application in Faraday isolators.
      PubDate: 2022-04-02
  • Rare earth monosilicates as oxidation resistant interphase for SiCf/SiC
           CMC: Investigation of SiCf/Yb2SiO5 model composites

    • Abstract: Abstract Model composites consisting of SiC fiber and Yb2SiO5 were processed by the spark plasma sintering (SPS) method. The mechanical compatibility and chemical stability between Yb2SiO5 and SiC fiber were studied to evaluate the potential application of Yb monosilicate as the interphase of silicon carbide fiber reinforced silicon carbide ceramic matrix composite (SiCf/SiC CMC). Two kinds of interfaces, namely mechanical and chemical bonding interfaces, were achieved by adjusting sintering temperature. SiCf/Yb2SiO5 interfaces prepared at 1450 and 1500 °C exhibit high interface strength and debond energy, which do not satisfy the crack deflection criteria based on He-Hutchison diagram. Raman spectrum analyzation indicates that the thermal expansion mismatch between Yb2SiO5 and SiC contributes to high compressive thermal stress at interface, and leads to high interfacial parameters. Amorphous layer at interface in model composite sintered at 1550 °C is related to the diffusion promoted by high temperature and DC electric filed during SPS. It is inspired that the interfacial parameters could be adjusted by introducing Yb2Si2O7−Yb2SiO5 interphase with controlled composition to optimize the mechanical fuse mechanism in SiCf/SiC CMC.
      PubDate: 2022-03-21
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Tel: +00 44 (0)131 4513762

Your IP address:
Home (Search)
About JournalTOCs
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-