ИСТИНА

The fundamental magnetic characteristics of R2Fe14B intermetallics are highly sensitive to atomic substitutions and interstitial absorption of light elements. In this work, both were combined, and the influence of the substitutions in the R-sublattice and hydrogen absorption on the magnetization of (RR’)2Fe14BHx (R is Tm or Er, and R’ is Nd) in magnetic fields up to 58T was studied. (Tm0.5Nd0.5)2Fe14B and (Er0.5Nd0.5)2Fe14B were prepared. By using direct hydrogen absorption, (R0.5Nd0.5)2Fe14BHx compounds were obtained with hydrogen content 0≤x≤5.5. Magnetic measurements of both the parent alloys and their hydrides were carried out on nanopowders. The strength of the inter-sublattice coupling in (Tm0.5Nd0.5)2Fe14B, (Er0.5Nd0.5)2Fe14B and their hydrides is estimated by analysing high-field magnetization data. Itis shown that hydrogenation weakens the inter-sublattice exchange interaction up to 45 %. (Tm0.5Nd0.5)2Fe14B, with the maximum hydrogen content of 5.5 at.H/f.u., reaches the field-induced ferromagnetic state at about 55 T.