Preparation and Magnetic Properties of Glass-Ceramics Containing α-Fe for Hyperthermia
Preparation and Magnetic Properties of Glass-Ceramics Containing α-Fe for Hyperthermia
复制标题
含α-Fe高温微晶玻璃的制备及磁性能
DOI：
10.2109/jcersj.105.833
复制
发表时间：
1997
影响因子：
1.1
通讯作者：
T. Kokubo
中科院分区：
文献类型：
--
作者：
Hiroyasu Konaka;F. Miyaji;T. Kokubo
铁磁性微晶玻璃有望作为癌症热疗的种子材料，特别是位于身体深处的癌症，因为当癌症受到交变磁场的作用时，肿瘤局部会产生滞后损失加热。在H2气氛下对α-CaO-SiO_2系玻璃进行热处理，得到了在CaO-SiO_2系玻璃基质中含有大量Fe-Fe微粉的微晶玻璃。α-Fe在70 0℃以上析出，随着热处理温度的升高，其微晶尺寸和含量逐渐增大，在110 0℃时分别达到150 nm和17mol%。随着热处理温度从650℃升高到1150℃，样品的饱和磁化强度从9增加到57emu·g-1，样品的矫顽力从650℃的50Oe增加到750℃的237Oe，然后随着热处理温度的升高而减小。700℃热处理的样品在300Oe和100 kHz下的产热最大，为3W·g-1。因此，由于α-Fe微晶玻璃具有较大的饱和磁化强度和/或矫顽力，因此，如果有高达10kOe的磁场，则其相对较低的发热量可能会显著增加。
Ferromagnetic glass-ceramics can be expected to be useful as thermoseeds for hyperthermia of cancer, especially cancer located at deep parts of body, since hysteresis loss heating locally occurs at the cancer when they are subjected to an alternating magnetic field. Glass-ceramics containing a large amount of α-Fe fine particles in a CaO-SiO2-based glassy matrix were obtained by heat treatment of Fe2O3-CaO-SiO2 glasses under H2 atmosphere. The α-Fe precipitated above 700°C, and its crystallite size and fraction increased with increasing heat treatment temperature to reach 150nm and 17mol% at 1150°C, respectively. The saturation magnetization of the specimen increased from 9 to 57emu·g-1 with increasing heat treatment temperature from 650 to 1150°C. The coercive force of the specimen increased from 50Oe at 650°C to 237Oe at 750°C, and then decreased with increasing heat treatment temperature. The specimen heat-treated at 700°C showed the maximum heat generation, 3W·g-1, under 300Oe and 100kHz. Thus reratively low heat generation of α-Fe-containing glass-ceramics could increase significantly if a magnetic field as large as 10kOe would be available, due to their large saturation magnetization and/or coercive force.