The effect of Mn and Al dopants on the beta-FeSi2 stabilization by a two step route: mechanical alloying and annealing

J. DESIMONI,; J. MARTÍNEZ; S.M. COTES; J. RUNCO; M.A. TAYLOR

JOURNAL OF ALLOYS AND COMPOUNDS

ELSEVIER SCIENCE SA

Año: 2009 vol. 477 p. 789 - 794

0925-8388

Al andMndopant influence on beta-FeSi2 phase formationwas studied using X-ray diffraction and Mössbauer spectroscopy. Samples of Fe(1−x)RxSi2 (R = Al, Mn with 0.00≤x≤0.12) were prepared by the simultaneous mill of pure Si, Fe and R, under Ar atmosphere followed by an annealing at 1123K during 4 h at 1.33×10^(−5) Pa. The results indicate that the addition of Al improved the stabilization of beta-FeSi2 phase, reducing the amount of epsilon-FeSi from 20% to 6%. Also a preferential substitution at the Fe- site II by Mn atoms in beta-FeSi2 can be inferred from the present study. The sequence of phase formation is summarised by two reactions that account for the milling and the annealing effects