Provided is a refractory product which is not impregnated with pitch or the like, wherein it has higher corrosion-erosion resistance and thermal shock resistance as compared to a refractory product subjected to pitch or the like-impregnation treatment. The refractory product which is not impregnated with tar or pitch is characterized in that, in terms of values of physical properties of a sample of the refractory product as measured after heat-treating the sample in a non-oxidizing atmosphere at 1200° C.: an apparent porosity is 7% or less; a total void volume of pores having a pore diameter of 1 μm or less is 80% or more of an integrated void volume of pores of the entire sample of the refractory product; and a gas permeability is 50×10.sup.−17 m.sup.2 or less.

A ceramic article and method of manufacturing. The ceramic article comprises a porous ceramic material having a microstructure comprising an interconnected network of porous spheroidal ceramic beads. The microstructure has a total open porosity defined as the sum of an open intrabead porosity of the beads and an interbead porosity defined by interstices between the beads in the interconnected network. The microstructure has a bimodal pore size distribution having an intrabead peak corresponding to the open intrabead porosity and an interbead peak corresponding to the interbead porosity. An intrabead median pore size of the intrabead porosity is less than an interbead median pore size of the interbead porosity.

A ceramic tool material, in particular with piezoelectric effect and a preparation method thereof, and a cutting tool. The ceramic tool material includes the following raw materials by weight: 30-70 parts of matrix material, 30-70 parts of piezoelectric material, 5-10 parts of binder, and 10-20 parts of reinforcing phase and can be made into cutting tools. The cutting tool has a piezoelectric effect and excellent mechanical properties and can convert the cutting force signal into the charge signal during machining. By collecting charge signals, a cutting force can be measured and ceramic cutting tool condition can be monitored. Cutting force measurement function and high mechanical properties are integrated. A ceramic tool material with piezoelectric effect can measure the cutting force on the premise by meeting the cutting performance requirements.

A sintered body includes a crystal grain containing silicon nitride, and a grain boundary phase. If dielectric losses of the sintered body are measured while applying an alternating voltage to the sintered body and continuously changing a frequency of the alternating voltage from 50 Hz to 1 MHz, an average value ε.sub.A of dielectric losses of the sintered body in a frequency band from 800 kHz to 1 MHz and an average value ε.sub.B of dielectric losses of the sintered body in a frequency band from 100 Hz to 200 Hz satisfy an expression |ε.sub.A−ε.sub.B|≤0.1.

Various embodiments of the present invention relate to reactive media including calcium. A reactive media includes a vitrified calcium silicate comprising reactive calcium. Various embodiments of the reactive media described herein are useful for removal of anionic impurities such as phosphate from water.

A dielectric ceramic composition including a first component and a second component. The first component comprises an oxide of Ca of 0.00 mol % to 35.85 mol % an oxide of Sr of 0.00 mol % to 47.12 mol %, an oxide of Ba of 0.00 mol % to 51.22 mol %, an oxide of Ti of 0.00 mol % to 17.36 mol %, an oxide of Zr of 0.00 mol % to 17.36 mol %, an oxide of Sn of 0.00 mol % to 2.60 mol %, an oxide of Nb of 0.00 mol % to 35.32 mol %, an oxide of Ta of 0.00 mol % to 35.32 mol %, and an oxide of V of 0.00 mol % to 2.65 mol %. The second component includes (by mass) at least (a) an oxide of Mn of 0.005% to 3.500% and (b) one or both of an oxide of Cu of 0.080% to 20.000% and an oxide of Ru of 0.300% to 45.000%.

To provide a sintered body with improved impact resistance due to impact absorption through plastic deformation before brittle fracture for an impact exceeding the fracture resistance of the sintered body, and/or a method for producing the sintered body.

A sintered body including: zirconia containing a stabilizer; and a region in which an impact mark is formed when an impact force is applied.

A capacitor body includes a plurality of dielectric layers and a plurality of internal electrode layers stacked alternately. The plurality of dielectric layers include crystal grains of barium titanate, a rare earth element, and silicon. The crystal grains include a first crystal grain and a second crystal grain. The crystal grains each include a surface layer as a shell and an interior portion surrounded by the shell as a core. The first crystal grain has a higher concentration distribution of the rare earth element in the shell than in the core. The second crystal grain has distribution in which a ratio of a concentration of the silicon in the core and the shell is lower than a ratio of a concentration of the rare earth element in the core and the shell in the first crystal grain.

The present disclosure relates to a porous ceramic media that may include a chemical composition, a phase composition, a total open porosity content of at least about 10 vol. % and not greater than about 70 vol. % as a percentage of the total volume of the ceramic media, and a nitric acid resistance parameter of not greater than about 500 ppm. The chemical composition for the porous ceramic media may include SiO.sub.2, Al.sub.2O.sub.3, an alkali component and a secondary metal oxide component selected from the group consisting of an Fe oxide, a Ti oxide, a Ca oxide, a Mg oxide and combinations thereof. The phase composition may include an amorphous silicate, quartz and mullite.

A process for the manufacture of inorganic fibres comprises: (a) selecting a composition and proportion of: (i) silica sand; (ii) lime comprising at least 0.10 wt % magnesia; and (iii) optional additives comprising a source of oxides or non-oxides of one or more of the lanthanides series of elements, or combinations thereof; (b) mixing the silica sand; lime; and optional additives to form a mixture; (c) melting the mixture in a furnace; and (d) shaping the molten mixture into inorganic fibres. The raw materials selection comprises composition selection and proportion selection of the raw materials to obtain an inorganic fibre composition comprising a range of from 61.0 wt % and 70.8 wt % silica; less than 2.0 wt % magnesia; less than 2.0% incidental impurities; and no more than 2.0 wt % of metal oxides and/or metal non-oxides derived from said optional additives; with calcia providing the balance up to 100 wt %; and wherein the inorganic fibre composition comprises no more than 0.80 wt % Al.sub.2O.sub.3 derived from the incidental impurities and/or the optional additives.