中文摘要：

研究了传统固相反应法制备所得xCa_（0.5）Nd_（0.5）（Mn_（0.7）Fe_（0.3））O_3-（1–x）Ca_（0.61）Nd_（0.26）TiO_3（0.1≤x≤0.25,CNMFT_x）多晶陶瓷相组成、显微结构、烧结性能与微波介电性能之间的影响关系。X射线衍射研究表明,在研究组分范围内CNMFT_x样品均为单一正交钙钛矿结构;当烧结条件为1 400℃/4 h,x=0.1~0.2时,Fe~（3＋）/Mn~（3＋,4＋）替代Ca_（0.61）Nd_（0.26）TiO_3中Ti~（4＋）后,相对介电常数（εr为88.5~77.5）、品质因子（Q·f为7 010~9 370 GHz）和谐振频率温度系数（τf为207.4×10~（–6）/℃~149.1×10~（–6）/℃）逐渐降低,而当x=0.25时,εr（73.4）与τf值（119.6×10~（–6）/℃）仍按规律降低,虽然此时样品晶粒尺寸更为均匀,但Q·f值（5 100 GHz）降幅增加。因此,对于ABO3型钙钛矿结构的微波介质陶瓷,当具有铁磁效应离子的添加量较小时,微波介电性能的变化符合预期规律;但当置换量达到一定比例时,铁磁性增加,导电性增强,巨磁电阻效应减小,致使微波陶瓷介电损耗增加。

英文摘要：

xCao 5Nd0.5（Mno.vFe0.3）O3-（1-x）Ca0.61Nd0.26TiO3（0.1 ≤x≤0.25, CNMFTx） ceramics were prepared by the solid state reaction method. The phases structure, microstructures, sintering behaviors and microwave dielectric properties of the ceramics were studied. XRD results show that an orthorhombic perovskite structure is formed in the CNMFTx compositions with x = 0.1-0.25. With an increasing of Fe3＋/Mn3＋,4＋ substitution for Ti4＋ in CNMFTx （x = 0.1-0.2） samples sintered at 1 400 ℃ for 4 h, the relative permittivity （εr）, quality factor （Q · J） and temperature coefficient of resonant frequency （τf） decrease gradually from 88.5, 9 370 GHz and 207.4×106/℃ to 77.5, 7 010 GHz and 149.1×10-5/℃, respectively. When x = 0.25, the er （73.4） and τfvalue （119.6× 10-6/℃） of the samples are still decreased in accordance with the expectation, however, an obvious decreasing Q τfvalue （5 100 GHz） is found in the sample with uniform grain size distribution. Thus, for the microwave ceramic dielectric materials （ABO3 perovskite structure）, a small number of ferromagnetism Fe3＋/Mn3＋,4＋ ions additive can make a coexistence in ferromagnetism and microwave dielectric properties. But an increasing proportion of these ions additive can also enhance the dielectric loss due to an increase in ferromagnetism, conductivity and a decrease in rnagnetoresistance.