Design of dielectric and pyroelectric properties by use of spark plasma sintering method

利用火花等离子烧结法（SPS），通过两种不同成分之间的成分级配，开发了一种在宽温度范围内具有高热释电系数的热释电材料的制备方法。在20 ~ 50℃范围内获得了具有较高热释电系数的热释电材料。在本研究中，通过两种成分的混合物对sps烧结体进行扩散处理，获得了类似的性能。用这种方法，裂纹往往是由于扩散引起的体积变化引起的。新开发的方法解决了这个问题。因此，新开发的方法可以应用于广泛的领域。为了获得缺陷少的材料，需要将起始材料固定在较高的温度下。然而，在高温下烧制会降低材料的烧结性。这是通过使用纳米铣削技术来克服的。利用SPS特性成功制备了BaNd_2Ti_4O_<12>/Bi_4Ti_3O_<12>/Bi_4Nd_2Ti_4O_<12>层合材料。以纳米氧化锌和氧化铌为原料，成功制备了纳米氧化锌和氧化铌。

A method of a fabrication of pyroelectric material that exhibits high pyroelectric coefficient over a wide temperature region was developed using spark plasma sintering method (SPS) by a gradation of composition between two different compositions. Conditions were widely determined and the pyroelectric material which exhibits high pyroelectric coefficient in the region between 20℃ and 50℃ was obtained. In the beguiling of this research, similar property was attained by a diffusion treatment of a SPS-sintered body from a mixture of two compositions. By this method, crack is often caused because of the volume change by diffusion. Newly developed method cleared this problem. So, the newly developed method can be applied to a wide area. In order to obtain a material having few defects, starting material is desired to be fixed at higher temperatures. However, firing at high temperatures lowers the sinterability of the material. This was overcome by a use of nano-milling technology. Preparation of BaNd_2Ti_4O_<12>/Bi_4Ti_3O_<12>/Bi_4Nd_2Ti_4O_<12> laminated material was also succeeded using the characteristics of SPS. As a preparation of starting material, methods to fabricate nano-sized zinc oxide and niobium oxide were succeeded.