The effects of elements with different melting points on epsilon-FeSi size in FeSi2 alloy

摘要

The size of epsilon-FeSi phase in iron disilicide with impurities was investigated in this study. The impurity was chosen according to different melting points which are Sn (232 degrees C), Pb (327 degrees C), Zn (420 degrees C), Al (660 degrees C), Ag (962 degrees C) and Gd (1341 degrees C). The mixture of each element was melted in a furnace under Ar atmosphere and the size of epsilon-phase was analyzed from SEM photographs. It was found that the size of epsilon-phase has some correlation with the melting point whereby the lower the melting point, the lower the size of epsilon-phase. The size of a 5% Sn sample was close to that prepared by the thermal quenching method. Data for Sn in the composition of 0.0-1.0% also reveals that the size of epsilon-phase tends to decrease with increasing Sn composition, up to a factor of 3-4 for 1.0% Sn. This finding could help reduce the annealing time for the peritectoid process (epsilon + alpha -> beta) due to initially smaller epsilon-phase size. (C) 2016 Elsevier B.V. All rights reserved.