Patent classifications
C04B2235/85
Dielectric ceramic composition and multilayer ceramic capacitor comprising the same
A dielectric ceramic composition includes a barium titanate (BaTiO.sub.3)-based base material main ingredient and an accessory ingredient, the accessory ingredient including dysprosium (Dy) and praseodymium (Pr) as first accessory ingredients. A content of the Pr satisfies 0.233 mol≤Pr≤0.699 mol, based on 100 mol of the barium titanate base material main ingredient.
Dielectric composition and electronic device
A dielectric composition includes main phases and Ca-RE-Si—O segregation phases. The main phases include a main component expressed by ABO.sub.3. “A” includes at least one selected from barium and calcium. “B” includes at least one selected from titanium and zirconium. “RE” represents at least one of rare earth elements. A molar ratio of (Si/Ca) is larger than one. A molar ratio of (Si/RE) is larger than one, provided that the molar ratio of (Si/RE) is a molar ratio of silicon included in the segregation phases to the rare earth elements included therein. An average length of major axes of the segregation phases is 1.30-2.80 times as large as an average particle size of the main phases. An average length of minor axes of the segregation phases is 0.21-0.48 times as large as an average particle size of the main phases.
ALUMINUM TITANATE-CONTAINING PARTICLES, AT-CONTAINING GREEN AND CERAMIC HONEYCOMB BODIES, BATCH MIXTURES, AND METHODS OF MANUFACTURE
Aluminum titanate-containing particles made up of a conglomerate of multiple partial grains. The aluminum titanate-containing particles are formed by breaking apart ceramic bodies along cracks, which are formed predominantly through the grains, rather than between the grains. Batch mixtures forming the aluminum titanate-containing particles, as well as batch mixtures utilizing the aluminum titanate particles are disclosed. Green bodies, such as green honeycomb bodies having peak intensity ratios (PIRs) in an axial direction of less than or equal to 0.50, ceramic honeycomb bodies, methods of manufacturing green honeycomb bodies, and ceramic honeycomb bodies are provided, as are other aspects.
ARMOR PLATING MADE OF FINE-GRAIN BORON CARBIDE AND SILICON CARBIDE
An antiballistic armor-plating component, includes a ceramic body made of a material comprising, as percentages by volume, between 35% and 55% of silicon carbide, between 20% and 50% of boron carbide, between 15% and 35% of a metallic silicon phase or of a metallic phase including silicon.
Ferrite sintered magnet
A ferrite sintered magnet comprises a plurality of main phase grains containing a ferrite having a hexagonal structure, wherein at least some of the main phase grains are core-shell structure grains each having a core and a shell covering the core; and wherein the minimum value of the content of La in the core is [La]c atom %; the minimum value of the content of Co in the core is [Co]c atom %; the maximum value of the content of La in the shell is [La]s atom %; the maximum value of the content of Co in the shell is [Co]s atom %; [La]c+[Co]c is 3.08 atom % or more and 4.44 atom % or less; and [La]s+[Co]s is 7.60 atom % or more and 9.89 atom % or less.
CERAMIC DIELECTRICS WITH HIGH PERMITTIVITY AND LOW DIELECTRIC LOSS AND PREPARATION METHOD THEREFOR
Disclosed is a polycrystalline ceramic dielectric comprising: crystal grain bulks made of a barium titanate-based ceramic; and grain boundaries comprising interfaces between the crystal grain bulks, wherein the composition of the grain boundaries is controlled using dopants. By controlling the grain boundary composition using dopants so that the dopants are distributed across a width of 5 nm or less and using a nano-sized, fine-grained barium titanate-based ceramic precursor, the grain boundary structure within the polycrystals may maintain electroneutrality, and their ferroelectricity may be controlled, thereby allowing for smoother polarization reaction. Accordingly, the present disclosure provides polycrystalline ceramic dielectrics that have dielectric properties such as high permittivity and low dielectric losses in a wide frequency range, a small amount of reduction in electric field-dependent relative permittivity, high temperature stability, non-reducibility under a reduction sintering condition, and resulting high insulation resistance, and a preparation method therefor.
CERAMIC ELECTRONIC COMPONENT
A ceramic electronic component includes a body including a dielectric layer and an internal electrode; and an external electrode disposed on the body and connected to the internal electrode. The dielectric layer has a perovskite structure represented by a general formula ABO.sub.3 as a main phase, and includes a region in which Dy is dissolved. In the region in which Dy is dissolved, an atomic ratio of a content of Dy dissolved in an A-site of the perovskite structure to a content of Dy dissolved in a B-site is 1.6 or more and 2.0 or less.
CERAMIC ELECTRONIC COMPONENT
A ceramic electronic component includes a body including a dielectric layer and an internal electrode; and an external electrode disposed on the body and connected to the internal electrode. The dielectric layer has a perovskite structure represented by a general formula ABO.sub.3 as a main phase, and includes a region in which Dy is solid solubilized. In the region in which the Dy is solid solubilized, an X-ray count of Dy solid-solubilized in an A-site of the perovskite structure measured by using Scanning Transmission Electron Microscopy-Energy Dispersive X-ray Spectroscopy (STEM-EDS) is AD, an X-ray count of Dy solid-solubilized in a B-site of the perovskite structure is BD, and an average value of AD/BD is 1.6 or more and 2.0 or less.
Ferrite sintered magnet and rotating electric machine comprising the same
A ferrite sintered magnet comprising an M type Sr ferrite having a hexagonal structure as a main phase, wherein the ferrite sintered magnet does not substantially comprise a rare earth element and Co, a content of B is 0.005 to 0.9% by mass in terms of B.sub.2O.sub.3, and a content of Zn is 0.01 to 1.2% by mass in terms of ZnO.
DIELECTRIC COMPOSITION AND MULTILAYERED ELECTRONIC COMPONENT COMPRISING THE SAME
A dielectric composition includes a main ingredient having a perovskite structure represented by ABO.sub.3, where A is at least one of Ba, Sr, and Ca and B is at least one of Ti, Zr, and Hf, and a first accessory ingredient. The first accessory ingredient comprises 0.1 mole or more of a rare earth element, 0.02 mole or more of Nb, and 0.25 mole or more and 0.9 mole or less of Mg, a sum of contents of the rare earth element and Nb is 1.5 mole or less.