Co_2Z钡锶铁氧体材料的高频磁性能

High-frequency magnetic properties of Co2Z barium strontium ferrite materials

采用固相法制备Sr2+部分取代Ba2+的Co2Z铁氧体材料(Ba1.5Sr1.5Co2Fe24O41),探究了预烧温度、烧结温度、烧结气氛等制备工艺对材料磁性能的影响,并用扫描电镜和XRD分析仪对材料的微观形貌和相成分进行了观察、测试。研究表明,当预烧温度为1250～1280℃时,起始磁导率随预烧温度的增高而降低,Q值(1GHz)随之增高。当烧结温度从1220℃升高到1280℃时,起始磁导率随之增高,Q值(1GHz)随之减小。当烧结气氛由空气改为氧气时,起始磁导率降低,Q值(1GHz)增高。1280℃下预烧2h、1240℃氧气气氛中烧结3h的材料磁性能较优,起始磁导率为4.2,品质因数Q值在1GHz时为11.3,截止频率高于1.8GHz。

Sr-doped Co2Z barium ferrite materials （Bal.5Sri.5Co2Fe24041） were prepared by conventional ceramic technique, and influence of preparation process, such as presintering temperature, sintering temperature and sintering atmosphere on their magnetic properties was investigated. The morphology and phase composition of the materials were tested by scanning electron microscope（SEM） and X-ray diffraction（XRD）. The result shows that, the initial permeability decreases and quality factor（1GHz） increases with increasing presintering temperature from 1250℃ to 1280℃. The initial permeability increases and the quality factor（1GHz） decreases with increasing sintering temperature from 1220℃ to 1280℃. When the sintering atmosphere is changed from air to oxygen the initial permeability reduces, and the quality factor（1GHz） increases. The optimun magnetic properties were obtained for sample presintered at 1280℃ for 2h and sintered at 1240℃ for 3h in oxygen atmosphere, with initial permeability of 4.2, quality factor of 11.3 at the frequency 1GHz, and the cut-off frequency of higher than 1.SGHz.