Phase relations of R-T-M ternary system, crystal structure and magnetic properties of R(T, M)13 compounds (R= light rare earth;T = Co, Fe;M = A1, Si) (I) —— Phase relations of R-T-M ternary system

Rare earth (R)-3d transition metal (T) intermetallic compounds have potential application as permanent magnets and other novel smart materials owing to their distinctive electronic structures. Since the saturation magnetization increases with the increase in the 3d transition metal content, T-rich intermetallic compounds are the most promising candidates for new magnetic materials. For example, a series of R1-δT5+2δcompounds can be formed by substituting dump-bell T-T atoms for the R atoms in RT5compounds with the CaCu5-type structure. For δ=1/2, which means that a dump-bell T-T atoms replaces one R atom in every two RT5units, there form RT12-type compounds with the ThMn12-type structure.For δ= 1/3, a dump-bell T-T atom substitutes for one R atom in every three RT5units,