摘要 对以六方CaCu 5 型结构结晶的Dy 1− x Y x Co 5 [ x =0, 0.2, 0.4, 0.6, 0.8, 1] 化合物进行了结构和磁化研究。晶格参数和晶胞体积随着 Y 浓度的增加而增加。在所有化合物中都观察到场冷却和零场冷却磁化数据之间存在较大的热磁不可逆性,这归因于畴壁钉扎效应。直流磁化强度和交流磁化率的温度依赖性表明,除 DyCo 5 和 YCo 5 外,所有化合物都显示出 5-300 K 范围内的自旋重定向转变。自旋重定向温度随着 Y 浓度的增加而降低。磁性排列样品的粉末 X 射线衍射图表明,DyCo 5 在室温下具有平面各向异性,而所有其他化合物都具有轴向各向异性。自旋重定向转变归因于随着温度升高,易磁化方向从 ab 平面到 c 轴的变化。发现除 DyCo 5 之外的所有化合物的各向异性场都非常高。已通过考虑由稀土和过渡金属亚晶格引起的贡献的变化来解释磁性。发现除
Abstract Thermalexpansion (th.e.) and low frequency (15 Hz) initial susceptibility χ∥ (real, χ∥, and imaginary, χ∥ components) measurements were performed between 3.2 and 300 K for the uniaxial RECo5 permanent magnet compounds (RE = Pr, Nd, Ho and Y) in the form of oriented powder samples along the c-axis, and also for polycrystalline ones of NdCo5 and DyCo5.2. Anomalies in the th.e. and χ∥ were detected
Thermal expansion and spontaneous magnetostriction of RCo5 intermetallic compounds
作者:A.V. Andreev、S.M. Zadvorkin
DOI:10.1016/0921-4526(91)90011-3
日期:1991.7
Thermal expansion of RCo5 compounds (R = Pr, Nd, Sm, Gd, Tb, Dy, Ho) is investigated by X-ray diffractometry on single crystalline samples in the temperature range 5-1300 K. All compounds undergo large spontaneous magnetostrictive deformations, the volume effect reaches 3.2 x 10(-2) at 5 K in HoCo5.5. The contributions to the volume effect from Co-Co and R-Co exchange interactions are determined by comparison with YCo5, Y being the nonmagnetic analogue of R.