摘要
为探讨热处理条件与纳米钡铁氧体磁性能的关系，文中采用X射线衍射（X—ray diffraction，XRD）、红外光谱（infrared spectrum，IR）、振动样品磁强计（vibrating sample magnetometer，VSM）、场发射扫描电子显微镜（field emission scanning electron microscopy，FESEM）分析纳米钡铁氧体组成、磁性能及粒度。研究发现：在800℃／4h或900℃／3h生成单相钡铁氧体纳米晶后，适当增加焙烧温度与时间可使纳米钡铁氧体的饱和磁化强度（舰）和剩余磁化强度（Mr）增加，但对矫顽力Hc影响不大；在适宜的焙烧温度与时间条件下纳米钡铁氧体有最大磁能积。在焙烧条件为800℃／4h时，纳米钡铁氧体的饱和磁化强度Ms=58．03A·m^2·kg^-1，剩余磁化强度Mr=35．91A·m^2·kg^-1，矫顽力Hc=474．90kA·m^-1，纳米粉末平均粒径在40-70nm。
Aim. At the beginning of this paper, we review recent publications and point out that, in order to obtain better and better inherent magnetic properties of BaFe12O19, customarily shortened to BaM, it is necessary to understand better the effect of heat treatment on its magnetic properties. In the full paper, we explain the effects in some details in this abstract, we just add some pertinent remarks to listing the two topics of explanation. The first topic is： experimental materials and method. In this topic, we use the X-ray diffractometer, infrared spectrometer, vibrating sample magnetometer and field emission scanning electron microscope to study the composition, magnetic properties and grain size of BaM. The second topic is： results and their discussion. Its four subtopics are： the phase constitution and generation of BaM intermediate products （subtopic 2. 1）, the effects of calcination temperature on the phase constitution and magnetic properties（subtopic 2.2）, the effect of calcination time on the phase constitution and magnetic properties （subtopic 2. 3） and the morphology of BaM and the comparison of its magnetic properties with those reported abroad（subtopic 2.4）. In subtopic 2.1, we find that the transitional phase of BaM occurs at the temperature of 500℃/4 h and that the primary phase of its intermediate product is γ- Fe2O3. Also in subtopic 2.1, we find that the saturated magnetic strength is 52.6 A · m^2·kg^-1 and the coercivity is close to zero. In subtopic 2.2, we point out that the single-phase BaM of proper grain size is formed at the temperature of 800℃/4h or 900℃/3h; increasing the temperature and time helps increase both saturated and residual magnetic strengths. In subtopic 2. 3, we observe that： when the BaM is calcined for 4 to 6 hours, the magnetic energy properties are the best; when the BaM is calcined for 6 hours and annealed for two hours, its magnetic properties are not affected. In subtopic 2.4, we compare the magnetic properties of the BaM with those reported abroad, the comparison results being summarized in Table 1.
出处
《西北工业大学学报》
EI
CAS
CSCD
北大核心
2007年第6期874-879,共6页
Journal of Northwestern Polytechnical University
基金
航天支撑技术基金(N5CH0001)资助
关键词
纳米钡铁氧体
磁性能
热处理
nanocrystalline barium ferrite （BaM）, magnetic property, heat treatment
