HIGH-FIELD MAGNETIZATION PROCESS IN R2FE14B AND R2FE17NX COMPOUNDS

General method of calculating magnetization curves in ternary system R-Fe-X is given, where R is a rare-earth element and X a non-magnetic element such as B. In this method the ferromagnetism of Fe sublattice is treated phenomenologically, while exchange and crystal field acting on R ions are exactly taken into account. Experimental data on R2Fe14B and R2Fe17Nx systems are summarized in comparison with the calculated curves. Detailed analyses have shown that in the light R compounds the inter-multiplet mixing via the R-Fe exchange interaction is important especially for the first-order magnetization process, which often occurs at low temperatures with external fields along the hard direction.