Development of sintering and joining processes of high performance ceramics for next generation by using high power millimeter-wave radiation

基于毫微微波辐射的接合和接合过程是通过使用毫微微波光谱学研究开发的，以制造高性能的陶瓷和基本性质的陶瓷动力。以下结果已获得：在研究中，关于澄清毫米波地区陶瓷粉的非电特性，硅碳粉的功率吸收是首次通过毫米波光谱仪测量的，并发现了吸收协同作用的增加，以增加粉尺寸、温度和自由碳的含量。第二，使用去除粉末密度和增加zirconia含量的红外常数显示出高值的铝-zirconia常数。新的定位辅助元件被开发为具有28 GHz毫米口径的定位硅镍的Yb_2O_3。波浪辐射和一个快速插入过程已成功地被制造成块状硅镍，其中只有一个小时低一个温度低一个约400 ° C以上。在传统方法中。快速Millimeter-Wave焊接工艺也被应用于具有约190 W/m·K的高温下的铝硝酸盐的制造工艺，成功地在200℃以下的温度下产生，在传统方法中的一个10个短路的时间，作为制造纳米晶体管Bulk材料的一个例子，由Millimeter-Wave加热的研究结果，纳米-powder Anatase的整合是由Millimeter-Wave加热进行的。在平均直径为300 Hv的硬度为200纳米的多孔块钛中发现的结果。进一步的，聚焦的毫米波光束过程允许在400℃以下的低温下结晶出粗糙的SrTiO_3薄膜，并具有良好的结晶化SrTiO_3薄膜，与高密度恒定相似的聚晶体块SrTiO_3薄膜实现了合成成功。

Sintering and joining processes based on millimeter-wave radiation were developed for fabricating high performance ceramics and fundamental properties of ceramics powders were investigated by using millimeter-wave spectroscopy. Following results were obtained.In the research on clarifying the dielectric characteristics of ceramics powders in the millimeter-wave region, power absorption of silicon carbide powder was first measured by millimeter-wave spectroscopy and it was found that the absorption coefficient increased with increasing the powder size, temperature and the content of free carbon. Secondly, the dielectric constant of alumina-zirconia showed high values with decreasing powder density and increasing zirconia content.New sintering aids containing Yb_2O_3 were developed for sintering silicon nitrides with 28GHz millimeter-wave radiation and a rapid sintering process was successfully established for fabricating bulk silicon nitrides which were sintered within only one hour lower a temperature which was lower by about 400℃ than those in conventional methods. The rapid millimeter-wave sintering process was also applied to the fabrication of aluminum nitride with high thermal conductivity of about 190 W/m・K was successfully produced at a temperature of 200℃ lower and at a sintering time of one-tenth shorter than those in conventional methods.Subsequently, as an example of fabricating nanocrystalline bulk materials, consolidation of nano-powder anatase was investigated by millimeter-wave heating, resulting in obtaining porous bulk titania with 200 nm in the average diameter with 300 Hv in the hardness.Further, focused millimeter-wave beam process enabled to crystallize amorphous SrTiO_3 films at a low temperature below 400℃ and well-crystallized SrTiO_3 films with high dielectric constant similar to polycrystalline bulk SrTiO_3 was synthesized successfully.