Electrical and Magnetic Properties of Nd2Fe14B Magnet in Demagnetized and Magnetized States at Low Temperatures
Below room temperature the spin reorientation phase transition was observed for Nd2Fe14B magnet with Tsr ～ 135 K. Spin reorientation refers to a change in the preferred direction of the M magnetization. The Nd2Fe14B magnet changes from a uniaxial or easy-axis material at T>Tsr, to an easy-cone material at T<Tsr. The transition from easy-axis to easy-cone anisotropy is an interesting physical phenomenon, which is important in a practical sense. The purpose of the present work is to study the electrical and magnetic properties of Nd2Fe14B magnet in the interval of temperatures ～ 15-273 K in demagnetized and magnetized states. For the first time measurements of electrical resistance (ft) and a complex magnetic susceptibility (X = X+ iX ) of Nd2Fe14B alloy in demagnetized state and at two directions of magnetization in a range of temperatures ～ 15-273 K were carried out. The following new effects were found out: (i) It was established that occurrences of the positive contribution to the value of p at the perpendicular magnetization and the negative contribution at the parallel magnetization, (ii) It was shown that, the value of the magnetic contribution in resistivity at the parallel magnetization, △ρII, has a minimum in a vicinity of temperature of the spin reorientation transition, Tsr. (iii) It was established the occurrence of maximums of X and X values in a vicinity of temperature of the spin reorientation transition, (iv) It was established that Tsr value at perpendicular magnetization goes down and at parallel magnetization increases in comparison with the demagnetized sample. The received data have the practical importance for the application of Nd2Fe14B based permanent magnets at low temperatures.
Nd2Fe14B magnet magnetocrystalline anisotropy spin reorientation phase transition electrical resistivity magnetic susceptibility
Alexander M.BOVDA Vera A.BOVDA Valerij V.DEREVYANKO Vitaly A.FINKEL Tatyana V.SUKHAREVA
National Science Center Kharkov Institute of Physics and Technology, National Academy of Science of Ukraine, ul.Akademicheskaya 1, Kharkov 61108, Ukraine
国际会议
北京
英文
92-96
2006-08-29（万方平台首次上网日期，不代表论文的发表时间）