Effect of iron-intermetallics on the fluidity of 413 aluminum alloy

The effect of Fe content on the fluidity of 413 aluminum alloy has been investigated in both un-modified and Mn-modified states by vacuum fluidity test. Increasing Fe decreases the fluidity due to the formation of beta-Al5FeSi and alpha-Al-15(Fe, Mn)(3)Si-2-intermetallic compounds. The effect of melt holding time was also studied. The fluidity of Mn-modified alloys decreases drastically with increasing holding time. Agglomeration of alpha-intermetallics and subsequent sludge formation is the main cause of fluidity descending. The fluidity of un-modified alloys is, however, less sensitive to holding time. Applying enough superheat and holding time, corresponding to segregation factor of the alloy, is an effective way to increase the fluidity of Mn-modified alloys by the dissolution of Fe-bearing intermetallics. (C) 2008 Elsevier B.V. All rights reserved.