Production of the Device for Measuring the Pressure Dependent Magnetization and its Application

3D过渡合金和化合物中磁矩的出现与磁性原子之间的距离密切相关。无论是直接压缩，还是不同离子半径的离子取代，都能有效地改变距离。这种化学压力有助于产生物理压缩手段难以实现的负压。通过考察化学压力和直接压缩效应，研究了Laves相中Gd&lt；1-x&Gt；Y_xCO_2的磁性。在本研究中，我们注意到夹持式微弹作为一种高压装置，并寻找能够产生高于1.5 Gpa的高压的良好的非磁性材料。应用于喷气发动机和火箭上的钛合金(Ti-6Al-4V)较轻(密度为4g/cc)，在低温下稳定，其磁性能表现出泡利顺磁性。4.2K时的磁化率为2.56×10~(-6)emu/g，使用过的高压容器(-50cc)在10kOe时的磁化强度为5emu/g，试件的力学性能优于Be-Cu合金。通过测量锰铜的电阻率，对常温以下高压容器内的压力进行了标定。以交流磁化率为例，测量了自旋触发器的临界温度随温度变化的压力效应。在NiAs型晶体结构中，当Mn磁矩沿c轴时，样品的体积比磁矩在c面时变大，磁矩的值也变大。

The appearance of the magnetic moment in the 3d transition alloys and compounds is closely related to the distance between the magnetic atoms. Not only the direct compression but also the substitution of ions with different ionic radius can change the distance effectively. This chemical pressure is useful to produce the negative pressure for which it is hard to be realized by the physical compression means. The magnetic properties of Gd_<1-x>Y_xCo_2 in Laves phase have been investigated by examining the chemical pressure and direct compression effect. In the present studies, we notice a clamp-type microbomb as a high pressure apparatus and searched the good nonmagnetic materials for yielding the high pressure more than 1.5 GPa. The titanium alloys (Ti-6Al-4V) which have been applied to jet engines and rockets is lighter (density = 4 g/cc) and is stable at low temperatures, and its magnetic properties show a Pauli paramagnetism. The magnetic susceptibility at 4.2 K is 2.56x10^<-6> emu/g and the value of the magnetization at 10 kOe for the used high pressure vessel (-50 cc) is 5 emu/g. The mechanical features of the test pieces show higher properties than Be-Cu alloys. Pressure in the high pressure vessel below room temperature has been calibrated by measuring the resistivity of Manganin. The pressure effect of the critical temperature on spin-flop depending on the temperature was measured with ac susceptibility as its application. When Mn magnetic moments are along c-axis in the NiAs-type crystal structure, the volume of the sample becomes larger comparing with when magnetic ones are in c-plane and the value of the moment also becomes large.