Alumina Crucible Research Articles

ChemInform Abstract: Eu3Ir2In15: A Mixed‐Valent and Vacancy‐Filled Variant of the Sc5Co4Si10 Structure Type with Anomalous Magnetic Properties.

AbstractThe new title compound is synthesized in 95% yield from mixtures of Eu, Ir, excess In as an active metal flux, and Si to nucleate crystal growth (alumina crucible, 1273 K for 6 h, followed by annealing at 1123 K for 72 h).

ChemInform Abstract: Synthesis, X‐Ray Rietveld Analysis, Infrared and Moessbauer Spectroscopy of R2FeSbO7 (R3+: Y, Dy, Gd, Bi) Pyrochlore Solid Solution.

AbstractLn2FeSbO7 (Ln: Y, Dy, Gd) and Bi2FeSbO7 are prepared by calcination of stoichiometric mixtures of Ln2O3 (Bi2O3), Fe2O3, and Sb2O3 in air (alumina crucible, 1100‐1150 °C, 24 h), the Bi variant by staged heating from 700 to 1000 °C.

ChemInform Abstract: Low‐Temperature Synthesis of Cu2CoSnS4 Nanoparticles by Thermal Decomposition of Metal Precursors and the Study of Its Structural, Optical and Electrical Properties for Photovoltaic Applications.

AbstractCu2CoSnS4 (CCTS) nanoparticles are prepared from a 1.85:1:1:12 molar mixture of Cu(OAc)2, CoCl2, SnCl2, and CS(NH)2 in EtOH which is ball milled prior to thermal decomposition (alumina crucible, 250‐450 °C, 1‐6 h).

Fabrication and phase characterization study of SnS thin films under controlled sulfur deposition temperature

SnS thin films were prepared from the multilayer of Sn and S using vacuum and atmospheric (atm) pressure thermal evaporation methods respectively, followed by vacuum annealing process at 360°C for 1.5 hour. For the multilayer, sulphur layer was deposited at 175°Cand 200°C 5 hr and 250°C for 2.5hr duration from alumina crucible under standard atm condition, whereas Sn film of thickness 10nm was coated alternatively under 1E-5 mbar using thermal evaporation method. XRD studies shows that at low sulfurization temperature (Ts) of 175°C Sn and Sn2S3 is present because of the low formation energy of Sn2S3 than SnS and by increasing Ts to 200°C SnS phase is formed confirm from XRD, with decreasing the intensity of Sn peaks which indicates that this temperature could accelerate the formation of SnS phase. Raman analysis also confirms the formation SnSphase(95±2, 190±2,218±2, 164±2, 290±4 cm-1) along with Sn2S3 (58 and 307 cm-1) and Sn phases (125cm-1). Raman analysis shows that the relative intensity (RI) (%) of Sn decreases and RI (%) of SnS increases systematically by increasing Ts. Importantly, the formation of tin oxide phases is not observed under any of these conditions as confirmed by Raman and XRD analysis. The mean particle size increases from 33nm (Sn) to 97nm (SnS) after sulfurization process as corroborated by AFM. The absorbance spectra clearly indicate a significant change in the absorbance by varying Ts. A broad absorption arises due to Sn in samples S1 and S4 which disappears in S2 and S3 due to formation of SnS phase, confirmed by Raman and XRD analysis.

ChemInform Abstract: Color‐Tunable Photoluminescence and Energy Transfer Properties of Single‐Phase Ba10(PO4)6O:Eu2+, Mn2+ Phosphors.

AbstractSingle‐phase Ba10‐x‐y (PO4)6O:xEu2+,yMn2+ phosphors are prepared by solid state reaction of stoichiometric mixtures of BaCO3, NH4H2PO4, Eu2O3, and MnCO3 (alumina crucibles, flowing 10% H2/90% N2, 1200 °C, 5 h).

ChemInform Abstract: Color Manipulation of Intense Multiluminescence from CaZnOS:Mn2+ by Mn2+ Concentration Effect.

AbstractSingle‐phase polycrystalline CaZn1‐xMnxOS (x = 0—0.1) is prepared by solid state reaction of stoichiometric mixtures of CaO, ZnS, and MnCO3 (alumina crucible, 1100 °C, 3 h).

ChemInform Abstract: Drastic Change of Electrical Conductivity in Pr2CuO4 by Isovalent La Doping.

AbstractPolycrystalline samples of Pr2‐xLaxCuO4.+‐.δ (x = 0—0.3) are prepared by firing La2O3, Pr6O11, and CuO in air (alumina crucible, 1000 °C, 50 h).

Mechanisms and Kinetics of Boron Removal from Silicon by Humidified Hydrogen

The removal of boron from silicon by top blowing of humidified hydrogen has been studied in the present work through experimental work, thermodynamic calculations, computational fluid dynamic modeling, and quantum chemistry calculations. The effect of process parameters; temperature, lance diameter, lance distance from the melt surface, gas flow rate, and crucible material on the kinetics of boron removal were studied. It has been shown that the rate of boron removal is decreased with increasing temperature due to the competitive reactions between silicon and oxygen as well as boron and oxygen, which can be confirmed with the increases of p SiO/p HBO in the system. The rate of boron removal is increased with increasing the gas flow rate due mainly to the better supply and transport of the gas over the melt surface, as confirmed by the CFD modeling. Moreover, the rate of boron removal in alumina crucible is the highest followed by that in quartz and graphite crucibles, respectively. Faster B removal in quartz crucible than that in graphite crucible can be attributed to more oxygen dissolves in silicon melts. The fastest boron removal in alumina crucible is attributed to the additional boron gasification through aluminum borate (AlBO2) formation on the melt surface. Thermodynamic properties of the AlBO2 species have thus been revised by quantum chemistry calculations, which were more accurate to describe the formation of gaseous AlBO2 than those in the JANAF Thermochemical Tables. The main chemical reactions for boron gasification from silicon melts are proposed as $$ {\text{In graphite, quartz and alumina crucible}}:\quad \underline{\text{B}} + \underline{\text{H}} + \underline{\text{O}} = {\text{ HBO}}\left( {\text{g}} \right) $$ $$ {\text{In alumina crucible}}:\underline{\text{Al}} + \underline{\text{B}} + \underline{\text{O}} = {\text{ AlBO}}_{2} \left( {\text{g}} \right) $$ Based on the obtained results, it has been proposed that boron removal from silicon melt by humidified hydrogen is controlled both by the chemical reaction for boron gasification and mass transport in the adjacent gas phase.

Erosion and corrosion of alumina refractory by ingot casting steels

This study investigated the corrosion of alumina-based refractories by alloyed steels. The alumina crucibles were physically characterized. Four steels with varying casting temperature and alloy contents were melted under argon atmosphere and the contact angles measured. Post-mortem, X-ray diffraction, optical and scanning electron microscopy and energy-dispersive X-ray spectrometry were used to analyze the erosion and corrosion. The refractory properties did not affect erosion and corrosion. No infiltration occurred. The contents of oxygen and deoxidizing steel alloys influenced the corrosion and erosion of the matrix. Firstly, manganese reacted to manganese aluminate. Silicon followed—forming manganese alumosilicates. For highest casting temperatures (1580°C) also mullite formed. At the steel–refractory-interface aluminum displaced the silicates, enhancing corrosion. Due to mismatching thermal expansions, spalling occurred for the steel 17CrNiMo76 respectively 1.6587 in which mullite formed. In the coarse fraction only chromium doped alumina formed.

ChemInform Abstract: Cubic Structure of the Mixed Halide Perovskite CH3NH3PbI3‐xClx via Thermal Annealing.

AbstractCubic MeNH3PbI3‐xClx films of 530 nm thickness and a large crystalline structure are obtained by vacuum deposition using MeNH3I and PbCl2 in the molar ratio of 3:1 as precursors in alumina crucibles, followed by thermal treatment at 70‐120 °C for 1 h.

ChemInform Abstract: Luminescence Properties of a Novel Reddish Orange Long‐Lasting Phosphorescence Phosphor Zn2P2O7:Sm3+,Li+.

AbstractZn1.998‐xP2O7:Sm0.002 ,Lix (x = 0.002, 0.02‐0.2) co‐doped phosphors are prepared by solid state reaction of stoichiometric mixtures of ZnO, NH4H2PO4, Li2CO3, and Sm2O3 in air (alumina crucible, 1.

Optical and electrical properties of pressureless sintered transparent (K0.37Na0.63)NbO3-based ceramics

Lead-free (1−x)(K0.37Na0.63)NbO3-xCa(Sc0.5Nb0.5)O3 (x=0.050, 0.070, 0.090, 0.095 and 0.100) transparent ferroelectric ceramics have been fabricated by pressureless sintering procedure. Transmittance of 0.91(K0.37Na0.63)NbO3-0.09Ca(Sc0.5Nb0.5)O3 ceramics sintered in sealed alumina crucible was 15% higher than those sintered unsealed in air. By increasing the content of Ca(Sc0.5Nb0.5)O3, the phase structure of (K0.37Na0.63)NbO3 ceramics transformed from orthorhombic to tetragonal symmetry first and then to pseudo cubic symmetry. The 0.91(K0.37Na0.63)NbO3-0.09Ca(Sc0.5Nb0.5)O3 ceramics exhibited high density (98%), high transmittance (60%) in the near-IR region and relatively good electrical properties (εr=1914, tanδ=0.037, Tc=147°C, Pr=6.88μC/cm2, Ec=8.49kV/cm). Meanwhile, the introduction of Ca(Sc0.5Nb0.5)O3 induced a composition fluctuation in the (K0.37Na0.63)NbO3 lattice and made the ceramics more relaxor-like, which would lead to a further reduction of light scattering. These results demonstrated that 0.91(K0.37Na0.63)NbO3-0.09Ca(Sc0.5Nb0.5)O3 could be promising lead-free transparent ferroelectric ceramics.

ChemInform Abstract: Synthesis, Crystal Structure and Magnetism of Eu3Sc2O5Fe2As2.

AbstractThe title compound is synthesized from a stoichiometric mixture of Eu, Sc, FeO, and As2O3 (alumina crucible, 1173 K for 20 h and sintering at 1373 K for 120 h).

ChemInform Abstract: Synthesis of Garnet‐Type Li7La3Zr2O12 by Coprecipitation Method.

AbstractThe title compound is synthesized by calcination (air, alumina crucible, 950 °C, 10 h) of a mixture of LiOH·H2O and a precursor obtained by coprecipitation from an aqueous solution of LaCl3, ZrOCl2, and LiOH.

ChemInform Abstract: Luminescence Properties of Dysprosium Doped Calcium Magnesium Silicate Phosphor by Solid State Reaction Method.

AbstractCaMgSi2O6:Dy3+ white light emitting phosphor is prepared by firing a stoichiometric mixture of CaCO3, MgO, SiO2, and Dy2O3 in air (alumina crucible, 1050 °C, 3 h).

ChemInform Abstract: Crystallographic and Magnetic Descriptions of a Novel Erbium Rich Aluminide: Er10Co1+xAl3‐x (x = 0.30).

AbstractEr10Co1.3Al2.7 is prepared by arc melting of the elements followed by annealing (alumina crucible in evacuated silica ampoule, 1123 K, 1 week).

ChemInform Abstract: Synthesis and Single Crystal Study of CuMn3As2 and Cu2Mn4As3.

AbstractSingle crystals of CuMn3As2 (I) and Cu2Mn4As3 (II) are obtained from the elements in a Bi flux (Cu:Mn:As:Bi = 0.8:1.2:1:12; alumina crucible in evacuated quartz ampoule, 850 °C, 10 h).

Microstructure evolution and interfacial reaction of TiAl–Si alloy solidified in alumina crucible

The microstructure evolution of Ti–43Al–3Si (at-%) alloy solidified in alumina crucible was investigated by directional solidification technology. After directional solidification, the microstructure of the alloy is consisted of γ-TiAl, α2-Ti3Al, ξ-Ti5Si3 phases and Al2O3 particles. There are three morphologies of ξ phases formed in the alloy, namely, long rod-like, cluster-like with eutectic morphology, and needle-like shape. The volume fraction of ξ phases decreases with increasing growth rates. Al2O3 particles broke from the crucible and enter into the melt by the thermal physical erosion. Al2O3 particles enrich in the liquid phase with the moving of solid-liquid interface, and are captured or entrapped by dendrites during solidification. The Al2O3 particles mainly distributed in the interdendritic region, and some particles exist in dendrites.

ChemInform Abstract: Synthesis, Structure, and Rigid Unit Mode‐Like Anisotropic Thermal Expansion of BaIr2In9.

AbstractLarge single crystals of the title compound are prepared from the elements using In as a reactive flux (alumina crucible, 1000 °C, 2 d, 50—70% yield based on Ba).

ChemInform Abstract: An Investigation of Magnetoresistivity Properties of an Y3Ba5Cu8Oy Bulk Superconductor.

AbstractA bulk ceramic Y3Ba4.74Cu8.07Oy superconductor is prepared by solid state reaction of Y2O3, BaCO3, and CuO (alumina crucible, 840 °C, 12 h) and characterized by SEM and magnetoresistivity measurements.