Magnetostriction and magnetic anisotropy in TbFe11TiHx (x=0,1) single crystals

Single crystals of TbFe11Ti and its hydride with tetragonal ThMn12-type str ucture were obtained. Magnetostriction measurements have been made on ToFe( 11)TiH(x) (x=0, 1) single crystals by the applied strain gauge method in th e temperature range from 77 to 400 K and in magnetic fields up to 13 kOe. M agnetization measurement along the main crystallographic directions of the tetragonal structure have been performed on RFe11TiHx (x=0, 1) single cryst als in applied high magnetic fields up to 120 kOe in the temperature range from 4.2 to 300 K. It was concluded that hydrogenation results in an increa se in rare-earth anisotropy that leads to the disappearance of the spin-reo rientation transition in the TbFe11TiH single crystal. Hydrogenation lead t o a change in sign of the magnetic anisotropy constant K, and the magnetost riction constant lambda (alpha ,2)(2). (C) 2001 Elsevier Science B,V. All r ights reserved.