Study On The Dielectric Material With High Breakdown Strength Used For High Capacitance Impulse Capacitance

The development of pulsed power technology increasingly requires the miniaturization and lightening of energy systems.Energy storage components occupy the largest part of the energy system,increasing the density of the dielectric material storage density of great significance.The influence of Bi₂O₃·3TiO₂?Abbreviation BT?doping,CaO doping,Bi(Mg_1/2Ti_1/2)?Abbreviation BMT?doping and preparation process on the dielectric properties,compressive strength and energy storage characteristics of?Sr,Pb?TiO₃ ceramics was investigated in this paper.The main contents are as follows:?1-x?Sr_0.84Pb_0.16TiO3_-xBi₂O₃·3TiO₂?x=0,0.03,0.07,0.09,0.14?ceramics were prepared by solid-state reaction.The effects of Bi₂O₃·3TiO₂ doping content on ceramic phase,Microstructure and dielectric properties.It is found that the increase of Bi₂O₃·3TiO₂ contributes to the growth of crystal grains,and the dielectric constant of the material is also increasing at room temperature.The Curie peak of the material also moves to the high temperature with the increase of the doping amount,and the obvious relaxation characteristic appears.When x=0.09,the ceramic has the best performance:?_r=3044,tan?=0.002,BDS=114.4kV/cm and J=0.702 J/cm³ at 100 kV/cm.?2?On the basis of 0.91Sr_0.84Pb_0.16TiO₃-0.09Bi₂O₃·3TiO₂,the influence of CaO doping on the composition,microstructure and dielectric properties of ceramics was studied.It was found that the addition of small amount of CaO could improve the dielectric constant of the ceramic material.With the increase of CaO content,the dielectric constant of the material decreased with the increase of CaO content.When the doping amount of CaO was 0.005,The dielectric constant of the material rose to about 3300,and itscompressivestrengthcomparedtoundopedsamples0.91Sr_0.84Pb_0.16TiO₃-0.09Bi₂O₃·3TiO₂ change is not great.?3?The solid-state method was also used to study the doping of Bi(Mg_1/2Ti_1/2)O₃into Sr_0.84Pb0.16TiO₃?SPT?ceramics,and the?1-x?SPT-xBMT?x=0,0.02,0.04?,0.06,0.08).As the x value increases,the breakdown strength increases,and the ceramic material exhibits relaxation properties.The ceramic material has the best performance at x=0.06:?r=1980,tan?=0.00325,BDS=16 kV/mm,and energy storage density J=0.544 J/cm³?E=11 kV/mm?.?4?Select the optimal solution of the above three groups of experiments,the use of isostatic pressing process to discuss the impact on the performance of their technology,the conclusion is that the isobaric pressure on Bi₂O3·3TiO₂ doped group almost no effect on CaO And the dielectric constant increases a lot.The field strength of the BMT-doped group is greatly affected,and its value increases obviously.