Investigation of the magnetic properties of Nd2Fe17 and Nd2Fe17Hx(x=3, 4.9) in high magnetic field

Through high magnetic field magnetization measurements performed in field u p to 200 kOe, the magnetic properties of ferromagnetic compounds Nd2Fe17, N d2Fe17H3 and Nd2Fe17H4.9 are investigated in the temperature range 4.2-300 K. The sample preparation and the interstitial element location in the unit cell are reminded. Powder samples embedded in a resin and then aligned at room temperature in a 10 kOe field are prepared in order to obtain oriented samples. Although the influence of the hydrogen insertion on the saturatio n magnetization is weak, the anisotropy constants are very sensitive to the hydrogen content and decrease strongly in the two hydrides. In Nd2Fe17H3 a n abrupt field-induced transition is observed in a large temperature range. It shows that the Nd anisotropy is deeply modified by the hydrogen inserti on. (C) 2000 American Institute of Physics. [S0021-8979(00)40208-2].