Experimental Investigation of Phase Equilibria in Fe–Ho System

Current study deals with the phase diagram evaluation of the Fe–Ho system. The alloys in the system have been studied by the means of SEM, EPMA, and DTA. The congruent melting phases in the system are: Ho 2 Fe 17 , HoFe 3 , HoFe 2 , and Ho 6 Fe 23 forms from the peritectic reaction. The temperatures and the compositions of the following eutectic reactions have been found: L ⇄ (Ho) + HoFe 2 (922 ± 1°C, 66 at % Ho), L ⇄ HoFe 3 + HoFe 2 (1290 ± 1°C, 30 at % Ho), L ⇄ Ho 6 Fe 23 + Ho 2 Fe 17 (1282 ± 3°C, 20 at % Ho), L ⇄ (γFe) + Ho 2 Fe 17 (1335 ± 1°C, 9 at % Ho).