Скачать или смотреть Ceramic Components in Production of Capacitors

Ceramic Components in Production of Capacitors Irrespective of their manufacturers, the ceramic components are in the forefront of the miniaturization tendency. Special manipulations with raw ceramics helped decrease the size of capacitors and create conditions for domination of the multi-layered ceramic capacitors in the field. The extremely low impedance of ceramics coupled with the relatively high capacitance often makes the developers choose the ceramic capacitance over the electrochemical ones. The ceramics are also demanded for because of their piezo electric properties, which facilitate generation of electricity and ferroelectricity. The piezoelectric constant in ferroelectric ceramics is much greater than in other natural materials. Besides, the process leads to spontaneous polarization and reverse spontaneous polarization. In 1950, as the barium titanate applications grew more popular, the ferroelectricity discovered already back in 1921, became a lot more important in the field of electronics. This ferroelectric material is built as an oxygen octahedron with common corners. Generally, all the ferroelectric materials can be further divided into three categories: organic polymers, ceramic polymer composites and substances containing radicals with hydrogen bonds. Among the materials structured as an oxygen octahedron with common angles, the barium titanate is considered a part of the perovskite family. The barium titanate is specifically ideally fitted for production of multi-layered ceramic capacitors, due to the large value of its dielectric constant under the room temperature. For example, for ceramics based on the barium titanate the dielectric constant can reach up to 7,000, whereas in other types of ceramics (like titanium dioxide) the constant can lie anywhere between 20 and 70. In the narrow temperature range the dielectric constant of the barium titanate can reach up to 15,000, whereas in the majority of popular ceramic and polymeric materials it does not exceed 10.