A method of making a refractory article is provided. The method includes: a) mixing a binder system, a refractory charge, and a second colloidal binder to form an aqueous slurry; b) casting the aqueous slurry into a mold; c) subjecting the mold containing the aqueous slurry to a temperature that is lower than a slurry casting temperature for a time sufficient to form a green strength article; and d) firing the green strength article at a temperature of at least 450 C. for a time sufficient to achieve thermal homogeneity, thereby forming a refractory article. Refractory articles made in accordance with the method have a unique combination of pore structure and mechanical properties.

The present invention relates to a boroaluminosilicate mineral material, a low temperature co-fired ceramic composite material, a low temperature co-fired ceramic, a composite substrate and preparation methods thereof. A boroaluminosilicate mineral material for a low temperature co-fired ceramic, the boroaluminosilicate mineral material comprises the following components expressed in mass percentages of the following oxides: 0.41%-1.15% of Na2O, 14.15%-23.67% of K2O, 1.17%-4.10% of CaO, 0-2.56% of Al2O3, 13.19%-20.00% of B.sub.2O.sub.3, and 53.47%-67.17% of SiO.sub.2. The aforementioned boroaluminosilicate mineral material is chemically stable; a low temperature co-fired ceramic prepared from it not only has excellent dielectric properties, but also has a low sintering temperature, a low thermal expansion coefficient, and high insulation resistance; it is also well-matched with the LTCC process and can be widely used in the field of LTCC package substrates.

A reflective particulate material includes a particulate substrate having high total solar reflectance, bulk and apparent densities and toughness, and a low dust index. The reflective particulate can have a total solar reflectance of 80% to 87%, a toughness of 1% or fewer fines, an apparent density of 2.75 g/cm.sup.3 or greater, and a dust index of 1 or lower. A method of manufacturing the reflective particulate material includes preparing a slurry of the particulate substrate, spray drying the slurry to form a spray dried particulate, crushing the spray dried particulate to form a crushed particulate, and heating/calcining the crushed particulate. The heated, crushed particulate may further be coated to form a coated roofing granule.

The present invention relates to a method for obtaining calcium aluminates for metallurgical use from non-saline aluminum slags by means of reactive grinding and thermal treatment.

Disclosed are a low-shrinkage, high-strength, and large ceramic plate and a manufacturing method thereof. The method comprises the following steps: (1) preparing a ceramic raw material powder; (2) subjecting an acicular wollastonite to surface coating with a silane coupling agent and to pre-dispersion with a fumed silica to obtain a pre-treated acicular wollastonite; and (3) thoroughly mixing the ceramic raw material powder and the pre-treated acicular wollastonite and granulating the resulting mixture, the amount of the pre-treated acicular wollastonite added being 10 wt % to 30 wt % of the ceramic raw material powder, and subjecting the resulting granules to dry pressing and sintering to obtain the large ceramic plate. The acicular wollastonite is incorporated into the manufacturing of the large ceramic plate to take full advantage of the reinforcing effect and low sintering shrinkage characteristics of the acicular wollastonite. The invention reduces sintering shrinkage and increases product strength.

A ferrite sintered magnet 100 comprises M-type ferrite crystal grains 4 having a hexagonal structure, two-crystal grain boundaries 6a formed between two of the M-type ferrite crystal grains 4, and multiple-crystal grain boundaries 6b surrounded by three or more of the M-type ferrite crystal grains 4. This ferrite sintered magnet 100 contains at least Fe, Ca, B, and Si, and contains B in an amount of 0.005 to 0.9 mass % in terms of B.sub.2O.sub.3, the two-crystal grain boundaries 6a and the multiple-crystal grain boundaries 6b contain Si and Ca, and in a cross-section parallel to a c-axis of the ferrite sintered magnet, when the number of multiple-crystal grain boundaries 6b having a maximum length of 0.49 to 5 m per cross-sectional area of 76 m.sup.2 is N, N is 7 or less.

A preparation method for a ceramic composite material, a ceramic composite material, and a wavelength converter. The preparation method comprises: preparing an aluminium salt solution and a fluorescent powder; dispersing the fluorescent powder into a buffer solution having a pH 4.5-5.5 to obtain a suspension; titrating the suspension with the aluminium salt solution to obtain a fluorescent powder coated with Al.sub.2O.sub.3 hydrate film; calcining the fluorescent powder coated with Al.sub.2O.sub.3 hydrate film to obtain a Al.sub.2O.sub.3-coated fluorescent powder; mixing aluminium oxide powder with a particle size of 0.1 m-1 m and aluminium oxide powder with a particle size of 1 m-10 m to obtain mixed aluminium oxide powder; mixing the Al.sub.2O.sub.3-coated fluorescent powder and the mixed aluminium oxide powder to obtain mixed powder, the Al.sub.2O.sub.3-coated fluorescent powder being present in 40%-90% by weight of the mixed powder; and pre-pressing and sintering the mixed powder to obtain the ceramic composite material.

The present invention relates to a boroaluminosilicate mineral material, a low temperature co-fired ceramic composite material, a low temperature co-fired ceramic, a composite substrate and preparation methods thereof. A boroaluminosilicate mineral material for a low temperature co-fired ceramic, the boroaluminosilicate mineral material comprises the following components expressed in mass percentages of the following oxides: 0.41%-1.15% of Na2O, 14.15%-23.67% of K2O, 1.17%-4.10% of CaO, 0-2.56% of Al2O3, 13.19%-20.00% of B.sub.2O.sub.3, and 53.47%-67.17% of SiO.sub.2. The aforementioned boroaluminosilicate mineral material is chemically stable; a low temperature co-fired ceramic prepared from it not only has excellent dielectric properties, but also has a low sintering temperature, a low thermal expansion coefficient, and high insulation resistance; it is also well-matched with the LTCC process and can be widely used in the field of LTCC package substrates.

A ceramic slurry for forming a ceramic article includes a binder, a first plurality of ceramic particles having a first morphology, a second plurality of ceramic particles having a second morphology that is different from the first morphology; and a photoinitiator. A method for using this slurry for fabricating ceramic articles is presented as well.

A low-temperature co-fired microwave dielectric ceramic material includes: (a) 85 wt % to 99 wt % ceramic material comprising Mg.sub.2SiO.sub.4, Ca.sub.2SiO.sub.4, CaTiO.sub.3, and CaZrO.sub.3, wherein a weight ratio of Mg.sub.2SiO.sub.4 relative to Ca.sub.2SiO.sub.4 is of (1x):x, a weight ratio of CaTiO.sub.3 relative to CaZrO.sub.3 is of y:z, and a weight ratio of entities of Mg.sub.2SiO.sub.4 and Ca.sub.2SiO.sub.4 relative to CaTiO.sub.3 is of (1yz):y, 0.2x0.7, 0.05y0.2, 0.05z0.4; and (b) 1 wt % to 15 wt % glass material composed of Li.sub.2O, BaO, SrO, CaO, B.sub.2O.sub.3, and SiO.sub.2.