The present disclosure relates to a magnesium-based raw material with low thermal conductivity and low thermal expansion and a preparation method thereof. According to the technical solution, 40-60 wt % fused magnesia particles, 30-40 wt % fine monoclinic zirconia powder, 5-20 wt % fine zirconium oxychloride powder, 0.5-1.5 wt % calcium hydroxide nanopowder, 0.2-0.5 wt % calcium hydroxide nanopowder, and 0.1-0.3 wt % maleic acid are stirred for 15 min to mix well in a high-speed mixing mill at a constant temperature of 25° C. to obtain a mixed powder; and the mixed powder is mixed through a ball mill at a constant temperature of 25° C. for 3 min, roasted in a high temperature furnace at 250-400° C. for 0.5-3 h, and finally cooled to room temperature. The magnesium-based refractory material prepared has the advantages of relatively low thermal conductivity, low thermal expansion coefficient, excellent dispersibility, and strong resistance to slag penetration and erosion.

There is provided a hydrogen-substituted garnet-type oxide containing at least Li, H, La and Zr and has an amount of hydrogen a (moll unit) per one unit of a garnet-type oxide in a range of ≤1.85.

A method for preparing nanometer MAX phase ceramic powder or slurry having a laminated structure by means of ball milling and regulating the oxygen content of the powder. Micron-sized MAX phase ceramic coarse powder is adopted as a raw material, during ball milling, a gas or a liquid-state gas having a special effect is introduced into a ball milling tank, and by means of multi-dimensional functions and regulation such as ball milling parameters and gas reaction, the nanometer laminated MAX phase ceramic powder or the slurry containing the component is obtained. The surface components and the activated state of the powder are regulated while the particle size adjustment control of the powder is realized.

A method of producing polycrystalline Y.sub.3Ba.sub.5Cu.sub.8O.sub.y (Y-358) whereby powders of yttrium (III) oxide, a barium (II) salt, and copper (II) oxide are pelletized, calcined at 850 to 950° C. for 8 to 16 hours, ball milled under controlled conditions, pelletized again and sintered in an oxygen atmosphere at 900 to 1000° C. for up to 72 hours. The polycrystalline Y.sub.3Ba.sub.5Cu.sub.8O.sub.y thus produced is in the form of elongated crystals having an average length of 2 to 10 μm and an average width of 1 to 2 μm, and embedded with spherical nanoparticles of yttrium deficient Y.sub.3Ba.sub.5Cu.sub.8O.sub.y having an average diameter of 5 to 20 nm. The spherical nanoparticles are present as agglomerates having flower-like morphology with an average particles size of 30 to 60 nm. The ball milled polycrystalline Y.sub.3Ba.sub.5Cu.sub.8O.sub.y prepared under controlled conditions shows significant enhancement of superconducting and flux pinning properties.

Provided is a production method that can easily produce a calcium carbonate porous sintered body. The production method includes the steps of: preparing a dispersion liquid containing calcium carbonate and a gelling agent; adding a foaming agent to the dispersion liquid, followed by stirring until foamy to make a foam; turning the foam into a gel; and sintering the gelled foam to produce a calcium carbonate porous sintered body.

Spherical ceramic-glass nanocomposite dielectrics made from ceramics and glasses that are separately pre-milled by mechanical ball milling using selected ball-to-powder weight ratios and combined to form a mixture that is ball milled. A stable liquid suspension of the milled mixture including an added dispersant such as polyacrylic acid to improve uniformity is spray dried through a nozzle and recovered product is annealed. The novel dielectrics have a microstructure where ceramic primary particles are uniformly distributed and fully embedded in a glass matrix. The dielectrics have a mean particle size of about 1-20 um and a sphericity of about 0.8 or higher which are suitable for fabricating multilayer ceramic capacitors for high temperature applications. The novel dielectrics afford decreased sintering temperature, enhanced breakdown strength, lower dielectric lose tangent, and lower costs. Calcium titanate zirconate with manganese-doping-based or barium titanate-based dielectric ceramics and alkali-free borosilicate glass produce superior nanocomposite dielectrics.

In an aspect, a Co.sub.2Z ferrite has the formula: (Ba.sub.1−xSr.sub.x).sub.3Co.sub.2+yM.sub.yFe.sub.24−2y−zO.sub.41. M is at least one of Mo, Ir, or Ru. The variable x can be 0 to 0.8, or 0.1 to 0.8. The variable y can be 0 to 0.8, or 0.01 to 0.8. The variable z can be −2 to 2. The Co.sub.2Z ferrite can have an average grain size of 5 to 100 nanometers, or 30 to 80, or 10 to 40 nanometers as measured using at least one of transmission electron microscopy, field emission scanning electron microscopy, or x-ray diffraction.

An ion conductor including: at least one oxide represented by Formulae 1 to 3

Li.sub.4±xM.sub.1−x′M′.sub.x′O.sub.4   Formula 1

wherein in Formula 1, 0≤x≤1 and 0≤x′≤1 , M is a Group 4 element,

M′ is an element of Group 2, an element of Group 3, an element of Group 5, an element of Group 12, an element of Group 13, a vacancy, or a combination thereof, with the proviso that when M is Zr, then x≠0, x′≠0 and M′ is Be, Ca, Sr, Ba, Ra, Cd, Hg, Cn, Ga, In, TI, an element of Group 3, an element of Group 5, or a combination thereof;

Li.sub.4−yM″O.sub.4−yA′.sub.y   Formula 2

wherein in Formula 2, M″ is a Group 4 element, A′ includes at least one halogen, with the proviso that when M″ is Zr, y≠0,

Li.sub.4+4zM′″.sub.1−zO.sub.4   Formula 3

wherein in Formula 3, 0<z<1, and M″′ is a Group 4 element.

Disclosed is a rapid, reproducible solution-based method to synthesize solid sodium ion-conductive materials. The method includes: (a) forming an aqueous mixture of (i) at least one sodium salt, and (ii) at least one metal oxide; (b) adding at least one phosphorous precursor as a neutralizing agent into the mixture; (c) concentrating the mixture to form a paste; (d) calcining or removing liquid from the paste to form a solid; and (e) sintering the solid at a high temperature to form a dense, non-porous, sodium ion-conductive material. Solid sodium ion-conductive materials have electrochemical applications, including use as solid electrolytes for batteries.

A method for fabricating a porous ceramic heating body, and a method of fabricating a heating body. The method for fabricating includes, in sequence, mixing, ball-milling, defoaming, molding, and drying, pore-forming agent discharging, sintering, and electrode leading. The whole method is simple, and by using a box furnace to sinter the green body under an oxidizing atmosphere and normal pressure, the fabricated ceramic heating body is heated uniformly and the heating efficiency is high.