The Effect of Lithium on the Microstructure and Morphology of Fe-Rich Intermetallic Compounds in 360 Cast Alloy
In this study, the effect of small additions of lithium on the microstructure and morphology of Fe-containing intermetallic compounds in A360 alloy has been investigated. Different Fe contents (1, 1.5 and 2%) were added into A360 alloy, and Li concentrations also varied from 0 to 0.5 wt. %. The image analysis results showed that, the maximum length of β-Al5FeSi plate in Li-modified specimens is changed significantly in comparison with non-modified ones. It is evident that the maximum reduction in the average length of Fe containing platelets occurs in specimens with 2% Fe. Also, the lowest changes in the length of intermetallic phases -as Fe content decreases- occur in the 0.5 wt% Li. At higher Li concentrations, the presence of Al-Li-Si intermetallics in the microstructure can provide undesirable condition. This intermetallic can be so damaging in mechanical properties especially in coarse shapes.
M.S.J. Hashmi, S. Mridha and S. Naher
N. Nasiri et al., "The Effect of Lithium on the Microstructure and Morphology of Fe-Rich Intermetallic Compounds in 360 Cast Alloy", Advanced Materials Research, Vols. 264-265, pp. 1782-1787, 2011