THE EFFECTS OF MN ADDITION FOR THE PREDICTION OF THE THIXOFORMABILITY OF FE-CONTAINING AL-SI BASED ALLOYS
M. V. Koshelev, E-mail:
A. G. Prigunova, E-mail:
A. G. Vernidub
Physico-Technological Institute of Metals and Alloys of the NASU, Kyiv
Abstract
The effects of Mn addition for the prediction of the thixoformability of Fe-containing Al-Si based alloys have been investigated by DTA and optical microscopy. The experimental findings clearly demonstrated that altered Mn/Fe ratios (up to 0.7) in the studied alloys can reduce temperature sensitivity of liquid fraction (dfL/dT0.3–0.5) and enlarge to a large extent the solidification temperature interval and the temperature window between 30% and 50% fraction liquid. Moreover, with increasing Mn/Fe ratio from 0.3 to 0.7 plate-like β-Al5FeSi phase transforms to a more compact α* - Al(FeMn)Si phase which are more favorable for the semi-solid forming technology.
Keywords: thixoformability, Al-Si based alloys, phase transformation
