摘要:
The present invention provides barium titanate semiconductive ceramic having low specific resistance at room temperature and high withstand voltage, which fully satisfies the demand for enhancing withstand voltage. The average ceramic grain size of the barium titanate semiconductive ceramic is controlled to about 0.9 &mgr;m or less. By this control, the ceramic possesses low specific resistance at room temperature and high withstand voltage fully satisfying a recent demand for enhancing withstand voltage and may suitably used for applications such as controlling temperature and limiting current, or in exothermic devices for constant temperature. Accordingly, the barium titanate semiconductive ceramic enables an apparatus using the same to have enhanced performance and reduced size.
摘要:
The present invention provides a barium titanate-based semiconducting ceramic which exhibits excellent PTC characteristic and which can be fired at a temperature lower than 1000.degree. C. The present invention also provides an electronic element fabricated from the ceramic. The semiconducting ceramic contains, in a semiconducting sintered barium titanate; boron oxide; an oxide of at least one of barium, strontium, calcium, lead, yttrium and a rare earth element; and an optional oxide of at least one of titanium, tin, zirconium, niobium, tungsten and antimony in which the atomic boron is0.005.ltoreq.B/.beta..ltoreq.0.50 and1.0.ltoreq.B/(.alpha.-.beta.).ltoreq.4.0wherein .alpha. represents the total number of atoms of barium, strontium, calcium, lead, yttrium and rare earth element contained in the semiconducting ceramic, and .beta. represents the total number of atoms of titanium, tin, zirconium, niobium, tungsten and antimony contained in the semiconducting ceramic.
摘要翻译:本发明提供一种钛酸钡系半导体陶瓷,其表现出优异的PTC特性,并可在低于1000℃的温度下烧制。本发明还提供了由陶瓷制成的电子元件。 半导体陶瓷在半导体烧结的钛酸钡中含有; 氧化硼 钡,锶,钙,铅,钇和稀土元素中的至少一种的氧化物; 和钛,锡,锆,铌,钨和锑中的至少一种的任选的氧化物,其中原子硼为0.005≤B/β= 0.50和1.0 B /(α-β) /=4.0其中α表示半导体陶瓷中含有的钡,锶,钙,铅,钇和稀土元素的原子总数,β表示钛,锡,锆,铌,钨的总原子数, 锑包含在半导体陶瓷中。
摘要:
The semiconducting ceramic material of the present invention containing BaTiO3 and having a positive temperature coefficient of resistance is endowed with high withstand voltage. In the semiconducting ceramic material, a boundary temperature defined at the boundary between a first temperature range and a second temperature range is 180° C. or more (e.g., 370° C.) higher than the Curie temperature, wherein the first temperature range is higher than the Curie temperature and the ceramic material has a positive temperature coefficient of resistance in the range, and the second temperature range is higher than the first temperature range and the ceramic material has a negative temperature coefficient of resistance in the range.
摘要:
A BaTiO3-type semiconducting ceramic material which has undergone firing in a reducing atmosphere and re-oxidation, wherein the relative density of the ceramic material after sintering is about 85–90%. A process for producing the semiconducting ceramic material of the present invention and a thermistor containing the semiconducting ceramic material are also disclosed.
摘要:
The present invention provides barium titanate powder having a withstanding voltage of 800 V/mm or more and a specific resistance at room temperature of 100 .OMEGA..multidot.cm or less, the specific resistance at room temperature undergoing substantially no time-course change. Barium titanate of the powder of the present invention assumes a cubic crystal system. The powder has a particle size of about 0.1 .mu.m or less; the ratio represented by BaCO.sub.3 /BaO as obtained through XPS is about 0.42 or less; the lattice constant is about 0.4020 nm or more; and the ratio represented by Ba/Ti is about 0.988-0.995.
摘要:
A ceramic electronic component includes a component body having semiconductive ceramic layers and internal electrodes. The semiconductive ceramic layers and the internal electrodes are alternately laminated. The semiconductive ceramic layers have a relative density of about 90% or less and contain no sintering additives. The component body is provided with an external electrode on each side thereof. The ceramic electronic component has a low resistance and a high withstand voltage.
摘要:
The present invention provides a semiconducting ceramic which possesses a dielectric strength of 800 V/mm or more and a specific resistance at room temperature of 100 &OHgr;·cm or less, the specific resistance at room temperature undergoing substantially no time-course change. The semiconducting ceramic is formed of a sintered semiconducting material containing barium titanate, wherein the average grain size of the semiconducting ceramic is about 1.0 &mgr;m or less and the relative spectral intensity ratio represented by BaCO3/BaO, which is determined by XPS at the surface of the ceramic, is 0.5 or less.
摘要:
A multilayer PTC thermistor reliably decreases the resistance by decreasing the thickness of ceramic layers composed of a BaTiO3 semiconductor ceramic and achieves a resistance close to the resistance calculated from the multilayer structure. The thermistor is adjusted to satisfy the conditions 5≦X≦18 and 4≦X·Y≦10, wherein X is a thickness (μm) of each ceramic layer disposed between adjacent internal electrodes and Y is a donor content (%) in the barium titanate semiconductor ceramic constituting the ceramic layers, Y being expressed in terms of (number of donor atoms/number of Ti atoms)×100.
摘要:
A semiconductive ceramic in which the B constant is maintained at about 4000 K or more at elevated temperature to thereby decrease power consumption, and the B constant is lowered less than 4000 K at low temperature so as to avoid unnecessary increase of resistance; as well as a semiconductive ceramic element using the same. The semiconductive ceramic is formed of a lanthanum cobalt oxide, which serves as the primary component, and, as a secondary component, at least one oxide of Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Ni, Cu and Zn. The semiconductive ceramic element is fabricated through use of the semiconductive ceramic and an electrode formed thereon.
摘要:
A ceramic element is formed by a rare earth and transition element oxide such as LaCoO.sub.3. The ceramic element is substantially isolated from the atmosphere by a case base, a case, etc.