ABSTRACT Porous hydrophobic ceramic membranes have been increasingly applied in advanced membrane-based separation processes such as Direct Contact Membrane Distillation (DCMD) due to their higher chemical and mechanical resistances. The development of novel ceramic membranes enhanced with porosity is based on conventional techniques such as extrusion and tape casting, and unique processing such as

ABSTRACT In this work, a modified sintering method, i.e. the three-step sintering technology, has been applied to fabricate the K0.5Na0.5NbO3 ceramics. The impact of the detailed sintering conditions on the sinterability, dielectric and ferroelectric properties of K0.5Na0.5NbO3 is systematically investigated. Attributed to the three-step sintering, the highest density of 4.07 g cm−3 can be observed

ABSTRACT The phase evolution studies of zirconia, with 4–16 mol-% doping of calcium, have been carried out after sintering the pellets at 1400°C. From the X-ray diffractometer patterns, it is evident that the zirconia exists only in the monoclinic phase. However, Rietveld refinement of calcium-doped zirconia revealed the stabilisation in the monoclinic and cubic phases. With increasing calcium doping

ABSTRACT With the recent interest in more efficient, comfortable, precise and minimally invasive surgical procedures and postoperative repairs, such as crown lengthening, there has been increasing research on the application of full digital technology in clinical scenarios. This clinical case describes an approach to crown lengthening and aesthetic restoration in a digital workflow using net-shaped

ABSTRACT Two steps were involved in the preparation of the porous mullite ceramics: preparation of porous green body by foaming method combined with gelcasting, using alumina, silica and AlF3 as raw materials and synthesis of needle-like mullite whiskers by vapor-phase reaction. Owing to the special pore structure of foaming method, the needle-like mullite crystals had enough space to develop with

ABSTRACT Flash sintering (FS) is becoming a popular densification route for high-temperature oxide ceramics because of its rapid sintering performance. In the current study, bar-shaped hydroxyapatite (HA) specimens were hung between two Pt wire electrodes and consolidated by FS through a direct electric field at a constant furnace temperature (1000°C or 1100°C) in air. The electric field facilitated

ABSTRACT Monolithic self-glazed zirconia is a new type of biomimetic zirconia that has been successfully used as crown and bridge restorations in the anterior and posterior regions. It exhibits excellent biomechanics and aesthetic properties through completely digital processing technology. This case presents a young patient’s aesthetic rehabilitation with self-glazed ultra-thin zirconia veneers by

ABSTRACT ZrB2 powders were synthesised by microwave heating using the sol–gel method for precursor with eight C6H14O6 (ZrOCl2·8H2O), boric acid (H3BO3), citric acid (I), and mannitol (as raw materials). The results show that the temperature at which the ZrB2 powder is completely synthesised by microwave heating is 1400°C, which is 300°C lower than the traditional way. XRD and SEM were used to characterise

ABSTRACT Owing to their lower costs and functional properties, the construction industry has been increasingly adopting synthetic organic polymer (SOP) materials into linings, interiors and non-load bearing structural components. While SOPs have favourable properties and characteristics at ambient conditions, the same materials often perform poorly under moderate-to-elevated temperatures such as that

ABSTRACT In this investigation, it was studied the effect of curing temperature on the mechanical properties of pastes made with calcium sulfoaluminate cements synthesised from industrial wastes at a relatively low temperature of 1100°C. Fluorgypsum, fly ash, aluminium slag and calcium carbonate were used as raw materials. The main phases of synthesis were calcium sulfoaluminate and gehlenite. Pastes

ABSTRACT Porous ceria for high temperature catalytic applications demands structural integrity concomitant with sinter resistance and improved gas permeability. The current state of the art hinges on complex synthesis methodologies which are not only expensive but also lack flexibility in pore tailorability. Hence, the development of porous scaffolds through low-cost processes without compromising

ABSTRACT Bare and functionalised haematite nanoparticles (NPs) are synthesised through the co-precipitation method and characterised using XRD, SEM, TEM, EDX, FTIR, and VSM. XRD confirmed the rhombohedral-based hexagonal structure of Fe2O3, while, TEM and SEM showed the formation of lamellar-shaped NPs with the grain size varied from 22 to 80 nm. VSM presented soft ferromagnetic behaviour. From in

ABSTRACT Implant-supported cement–screw-retained crowns combine the advantages of screw-retained and cement-retained crowns. However, the occlusal screw access hole interrupts porcelain integrity, which may result in porcelain cracks or fractures. There is insufficient scientific evidence to prove that screw access holes affect the fracture load of implant-supported monolithic zirconia crowns. In this

ABSTRACT The latest technological requirement demands a huge (but sometimes challenging) variety of properties which perhaps are impossible in monolithic or traditional materials. This has innovated the introduction of reinforcement in traditional materials such that the resulting composite material would be an advantage for the collaborating influence of the combined matrix and the reinforcement.

ABSTRACT Cement mixture with calcite-ettringite seeds (CE seeds) was investigated in terms of early hydration and mechanical property. The ettringite crystals of ettringite seeds (E seeds) exhibited needle-like shapes with lengths of approximately 3 μm, and the ettringite crystals of CE seeds exhibited rodlike shapes with lengths less than 1 μm. A dense growth of network-structured ettringite and calcium

ABSTRACT The electrolyte supported intermediate temperature solid oxide fuel cell (IT-SOFC) based on Bi4V2O11 (BIVOX) ceramic stabilised by doping with La was investigated. By adding La to the initial composition of BIVOX, stabilisation of the good oxygen ion-conductive γ phase has been achieved. La addition has significantly increased the lifetime of SOFC due to the improved thermodynamic stability

ABSTRACT Zirconolite (CaZrTi2O7) has been identified as a candidate ceramic wasteform for the immobilisation and disposal of Pu inventories, for which there is no foreseen future use. Here, we provide an overview of relevant zirconolite solid solution chemistry with respect to Ce, U and Pu incorporation, alongside a summary of the available literature on zirconolite aqueous durability. The zirconolite

ABSTRACT The constitutive response of ceramics matrix composites (CMCs) under arbitrary loading and loading was studied. A method for determining the distribution of slip regions under arbitrary loading was proposed based on the shear lag model and slip law. Furthermore, a method for judging the closure of the matrix cracks was given based on the assumption that the fibre strain consists of the elastic

ABSTRACT Porous Yb2O3 ceramic (55%) was pressureless sintered at 900°C for four hours in air. The crystal structure of Yb2O3 was confirmed to be cubic ( Ia3¯) with c = 10.43731 Å by neutron diffraction. The spectral vibrational signature of Yb2O3 was also confirmed by micro-Raman spectroscopy. Yb2O3 is an amphoteric oxide with both acid and base character, which presents the potential for producing

ABSTRACT Zirconia containing 12 mol-% cerium oxide ceramics were prepared by solid state reaction utilising the conventional, fast firing and two-step sintering methods. The sintering temperature and time were varied aiming to determine ideal sintering profile for these methods. The monoclinic and tetragonal phase contents, microstructure and electrical conductivity of dense specimens were investigated

ABSTRACT We propose an innovative methodology to quantify the dependence of grain growth with respect to current density during flash sintering of zirconia (3YSZ) (field set under a nominal current limit of 150 mA mm−2. This was achieved by using a notch (0.5 mm deep and 1.5 mm wide) located in the middle of a dog-bone specimen, allowing an uneven current distribution (ranging from 3 to 670 mA mm−2)

ABSTRACT Herein, Pb0.95Ba0.01Sr0.04(Zr0.53Ti0.47)O3 piezoelectric ceramics comprising 0.25 wt% MnCO3, 1 wt% LiBiO2 and 0.06 wt% CuO (PBSZT-LBCu-Mn ceramics, abbreviated as Mn0.25) were prepared via a conventional method at a low firing temperature of ∼900 °C. The phase structure and temperature-dependent electrical properties were systematically investigated. The product composition possesses the following

ABSTRACT The enhancement of surface acidity for tungsten-doped CeTiOx was investigated through electronic structure. Tungsten doping increased the ratio of Ce3+ from 12.0% to 29.6%, which was confirmed by XPS. The doped tungsten was present as W5+ in a ratio of 71.5%. In O K-edge XAS spectra, increase in Ieg/It2g indicated the formation of oxygen vacancies through tungsten doping. The decrease in W

ABSTRACT Tooth discolouration and the existence of metallic substrates increase the difficulty of restoration to reproduce natural and aesthetic appearance. The commonly used veneered zirconia restorations have a high risk of porcelain chipping, and the monolithic zirconia restorations cannot always achieve satisfying aesthetics. The newly developed self-glazed monolithic zirconia restorations digitally

ABSTRACT In this study, paste backward extrusion is introduced for fabrication of sodium beta-alumina electrolyte closed-end tubes (with a wall thickness of 1 mm and external diameter of 8.0 mm). For this purpose, the two-piece extrusion die was designed and extrudable water-based paste was prepared by using sodium beta-alumina powder, polyvinyl pyrrolidone, as a binder, and ethylene glycol as a plasticizer

ABSTRACT The R2O–CaO–MgO–Al2O3–SiO2–Fe2O3 glass ceramics was prepared using granite wastes and Fe2O3. The effect of Fe2O3 on crystallisation and properties of glass ceramics was studied. Results show that the crystalline phases were Fe2TiO5 and K(NaCa)Mg5Si8O22F2 when the content of Fe2O3 was low. The main crystalline phase was Fe1.5Ti0.5O3 when the content of Fe2O3 was high. With the increase of Fe2O3

ABSTRACT Silicon carbide (SiC) fibres are widely used as promising reinforcement in ceramic matrix composites due to their excellent mechanical and thermal properties. In this work, sub-micrometer SiC fibres were prepared by electrospinning using polycarbosilane as the precursor, followed by curing in air and pyrolysing at high temperatures. The effect of the microstructure of SiC fibres on mechanical

ABSTRACT The material properties and damage characteristics of lead zirconate titanate(PZT) ceramics were investigated at various temperatures. A positive voltage was obtained when the sample was cooled from 20°C to −190°C, while a negative voltage was obtained when the sample was heated from −190°C to 180°C. The difference between the positive and negative values depended on the thermal stress. Compressive

ABSTRACT In this study, the impinging stream-rotating packed bed and precipitation method were used to continuously prepare Fe and Co co-doped Titanium Dioxide by in-situ modification. With TiOSO4 solution containing Fe and Co2+ and NH3·H2O were sprayed on the packing and sheared by the packing that rotated at a high speed, resulting in improvement of microscopic mixing. The prepared catalyst is anatase

ABSTRACT In this study, the compositions 4TaC-1HfC and 1TaC-1HfC ceramics were prepared via hot pressing 5 vol.-% La2O3-doped TaC-HfC powder mixtures in temperature range of 1700–2000°C. The effect of sintering temperature on the densification of the two compositions was assessed. Highly dense TaC-HfC ceramics were obtained after hot pressing at sintering temperature of 1750°C or greater, depending

ABSTRACT In this paper, the effect of rice husk ash (RHA), as silicate impurities, on the microstructure and mechanical properties of calcium aluminate cement concrete (CACC) is explored. Various mechanical tests, including tests for obtaining the compressive, splitting tensile, flexural strengths and elastic modulus, were performed on different mixture designs containing different volume percentages

ABSTRACT An improvement in the thermoelectric properties of calcium cobaltite ceramics (Ca3Co4O9) was demonstrated through a modified co-precipitation method and lanthanum doping. With highly reactive precursors derived from the modified method, the energy consumption was conserved due to an apparent decrease in calcination duration. The conventional sintering produced a layer structure with the interconnected

ABSTRACT Zirconia is a bioinert ceramic biomaterial. Zirconia having composition of 97% Zirconia oxide and 3% Yttria oxide finds its vital application in the field of dental ceramics as an implant material for having good inert characteristics like minimum interaction with the adjacent tissues and exhibits good aesthetic property. This paper presents the in-vitro tests conducted to evaluation toxicity

ABSTRACT In order to improve the detection efficiency and image quality of Si3N4 ceramic bearing balls surface defects, digital image processing technology is used to analyse the information characteristics of Si3N4 ceramic bearing balls surface. A multi-scale decomposition enhancement algorithm for surface defect images of Si3N4 ceramic bearing balls based on the stationary wavelet transform is proposed

ABSTRACT Non-stoichiometric oxynitride with a composition of EuTaO1.75N1.25 was synthesized in <10 min through urea route combined with modified pressureless spark plasma sintering apparatus. The electronic properties of EuTaO1.75N1.25 was investigated by first-principles calculations. X-ray powder diffraction revealed that EuTaO1.75N1.25 crystallized with the cubic perovskite-type structure, S.G.

ABSTRACT This paper develops a numerical model that contained random lip-shaped matrix cracks based on the maximum energy release rate criterion for the prediction of failure progress of Continuous Fibre-reinforced Ceramic Matrix Composites (CFCC) under transverse tension. Fibre distribution layout is created based on the actual microstructure and the Random Sequential Adsorption algorithm is used

ABSTRACT This paper develops a numerical model that contained random lip-shaped matrix cracks based on the maximum energy release rate criterion for the prediction of failure progress of Continuous Fibre-reinforced Ceramic Matrix Composites (CFCC) under transverse tension. Fibre distribution layout is created based on the actual microstructure and the Random Sequential Adsorption algorithm is used

ABSTRACT Alternative fuels are being used increasingly to reduce energy costs and benefit the economics of electric power industries. Olive residues could be among those alternative fuels. This paper investigates the potential use of olive biomass ash (OBA) to develop a new sustainable binder (geopolymer composite). Refined binder chemistry was developed where the alkali and silica contents of the

ABSTRACT Natural wood is a ready-to-use template for making porous silicon carbide (SiC) body. Biomorphic β-SiC was synthesised from wood of a mango (Mangifera Indica) tree. Carbon template was made by carbonising this wood at 1000°C in argon gas atmosphere. Thus formed template was repeatedly infiltrated with a mixture of tetraethyl-orthosilicate (TEOS) (in alcohol) and oxalic acid solution (aqueous)

ABSTRACT Fully dense WC-Al2O3 platelet composites with VC additive were fabricated by hot-press sintering. Their mechanical properties and microstructure were examined. The contents of Al2O3 platelet (Al2O3pl) and VC were optimised. The fracture toughness of WC-based composites would be obviously improved with Al2O3pl addition. The defined addition of VC was beneficial for the densification and improved

ABSTRACT The gas-tight joining between yttrium-stabilised semi-closed zirconia ceramic tube and 06Cr19Ni10 stainless steel tube was achieved by using a self-made Ag–27Cu–4Ti paste filler material, where the joint form was an outer sleeve joint. After brazing, the samples were subjected to thermal shock (−50°C to 150°C) and thermal cycling tests (room temperature to 600°C), respectively. The sealing

ABSTRACT The gas-tight joining between yttrium-stabilised semi-closed zirconia ceramic tube and 06Cr19Ni10 stainless steel tube was achieved by using a self-made Ag–27Cu–4Ti paste filler material, where the joint form was an outer sleeve joint. After brazing, the samples were subjected to thermal shock (−50°C to 150°C) and thermal cycling tests (room temperature to 600°C), respectively. The sealing

ABSTRACT Solid solutions of Ba(Ti1−x Zr x )4O9 (0 ≤ x ≤ 0.8) were fabricated via mixed oxides, solid state route. The phase, microstructural and dielectric properties of the fabricated samples were investigated. A structural phase transition was observed from orthorhombic (Amm2) to tetragonal (P4/mmm) with increasing Zr4+ contents (x ≥ 0.6). The dielectric constant (ϵr ) increased with the substitution

ABSTRACT Iron boride coatings obtained by the CVD-based thermal diffusion process are proposed and evaluated for the first time for high-temperature corrosion and scaling conditions in geothermal power generation. The testing results in different corrosion environments are presented. The influence of structure and surface composition on the materials’ performance is demonstrated. The dual-layer boride-based

ABSTRACT Carbon steel is a widely used structural material; however, it lacks corrosion resistance in water environments. An alternative approach to overcome this challenge is to implement the deposition of inherently corrosion-resistant ceramic coatings. SiC/C/Al coatings were developed at 700°C, using polycarbosilane in combination with Al and C, which were included as active and passive fillers

ABSTRACT Nepheline porous ceramics with improved strength and well thermal insulation performance were synthesised at 850–1000°C by a foam-gelcasting technology, using waste zeolite powders, triethanolamine lauryl sulphate and xanthan gum respectively as the starting materials, foaming agent and gelling agent. The effect of sintering temperatures and solid contents on the physical and thermal properties

ABSTRACT Coral reefs provide habitat for most oceanic life forms, however, they are declining worldwide due to pollution, increased ocean temperature, diseases and other factors. In this paper, structural and mechanical properties of endangered coral (Acropora cervicornis) skeletons cleaned by chemical bleaching and biological processes were studied. The structure of CaCO3 aragonite skeleton is porous

ABSTRACT The effect of BaO on the structure and properties of bismuth-based low-melting sealing glasses (Bi2O3–B2O3–ZnO–SiO2–Al2O3–BaO) were investigated by FTIR, 27Al NMR and DSC. The results showed that when BaO content was less than or equal to 3 wt-%, BaO provided (O2–) free oxide ions, which made [AlO6] transform into [AlO4] and made [BO3] transform into [BO4]. The increase of [AlO4] and [BO4]

Since it was initiated in March 2011, in Stockholm, Sweden, the International Workshop on Advanced Ceramics and Technologies for Dentistry (ACT4D) has been held regularly, each time ended up a volume of publication as special issue either of Journal of the European Ceramic Society or of the Advance in Applied Ceramics. The articles included in this special issue were selected from those works presented

ABSTRACT Three kinds of commercial zirconia powders with compositions (1–x)ZrO2–xY2O3 (x = 0, 3 and 8 mol-%) were sintered at 1300–1600°C in their free-standing granules. The as-received powder with x = 0 is monoclinic (M) phase. Both as-received powders with x = 3 and 8 show mixed phases dominated by tetragonal (T). The powder with x = 0 returned to M phase at room temperature after high temperature

ABSTRACT Porous SiC ceramics were prepared based on precursor conversion method using liquid hyperbranched polycarbosilane (LHBPCS) as the preceramic polymer and expandable microsphere (EMS) as the pore foaming agent. By optimising the content of free radical initiator, the cross-linking process of LHBPCS is synchronised with the foaming process of EMS. The addition of EMS had no serious effect on

ABSTRACT Reasonable zirconia surface pretreatment results in excellent bond strength. This study compared the effects of different surface treatments on the shear bond strength of zirconia. A total of 48 zirconia discs were divided into six separate groups (n = 8) including a Control (CL), Alumina particle blasting (AP), Silica coating (SC), Alumina particle blasting and silica coating (AS), Femtosecond

ABSTRACT In this study, the sol–gel method was used to add MgO and SrBr2 to biografts containing Ca(NO3)2·4H2O, SiO2, P2O5, H3BO3 and AgNO3. In addition, urea (15–35% by weight) was added to these biografts in different ratios. FTIR, XRD and SEM–EDX analyses were performed in order to observe the morphological effects. Antibacterial tests were carried out using S.aureus and E.coli bacteria. As a result

ABSTRACT The buildability of cementitious structure for 3D printing was investigated in terms of ettringite formation and hardening behaviour with packing density of OPC-CSA blends. The packing density of the OPC was 2.34 g cm−3, increased to 2.39 g cm−3 when 10 wt-% CSA was added, and then began to decrease to 2.37 g cm−3 at 15 wt-% CSA addition. The exothermic peak was observed at around 114°C which

ABSTRACT In this study, we carried out a simple surface modification of zinc oxide nanoparticles (ZnO NPs) using didodecyldimethylammonium bromide (DDAB) as a cationic surfactant. The crystallographic properties, optical absorption, and morphology of the ZnO NPs did not change after the surface modification. The FT-IR spectra of the surface-modified ZnO NPs (SM-ZnO) showed the characteristic peaks

In this study, we carried out a simple surface modification of zinc oxide nanoparticles (ZnO NPs) using didodecyldimethylammonium bromide (DDAB) as a cationic surfactant. The crystallographic properties, optical absorption, and morphology of the ZnO NPs did not change after the surface modification. The FT-IR spectra of the surface-modified ZnO NPs (SM-ZnO) showed the characteristic peaks of DDAB,

ABSTRACT Phosphates particularly zinc phosphates is a family of conventional dental cements that was developed a century ago and has been in use until today despite the fact that a number of new resin composite cements have been introduced in the market through the years. A close inspection of the in vivo aged samples provides insides to the margins and to the micro-leakage thus would sharpen the understanding

ABSTRACT Using a simple solid-state mixed oxides method, dense La2Mo2O9 ceramics with a relative density higher than 94% were prepared at relatively low sintering temperatures (<960°C) and the crystal structure, dielectric properties were studied in some details. Splitting peaks in XRD profiles evidenced the presence of monoclinic phase. Optimum dielectric properties at microwave frequency were achieved

ABSTRACT The aim of the study was to evaluate the marginal adaptation of various hybrid ceramics inlays before and after thermal cycling. Twenty-four extracted human molars were received inlay preparation, and randomly divided into three groups (n = 8/group). Specimens were restored with Ceramage by experienced technician, Enamic or Lava Ultimate by CAD/CAM using CEREC Omnicam. After cementation, all

ABSTRACT Cutting performances of TiCN–HfC (TH) and TiCN–HfC–WC (THW) ceramic tools in dry turning hardened AISI H13 was investigated. The optimal cutting parameters – cutting speed of 110 m/min, feed rate of 0.1 mm/rev and depth of cut of 0.15 mm – were obtained by the orthogonal experiment. At the optimal cutting parameters, the tool life of TH was 82 min higher than that of THW, which indicated that