Abstract | The solidification of Al-4.6Cu-0.5Fe-0.5Mn (206 type) cast alloy has been studied using Thermal Analysis, Differential Scanning Calorimeter, Scanning Electron Microscopy, Electron Back-Scattered Diffraction (EBSD), and Transmission Electron Microscopy (TEM). It is interesting to note that an iron-rich intermetallic phase, Al3(FeMn), is experimentally observed to be dominantly present in the fully solidified cast structure of the experimental 206 cast alloy, in addition to β-Fe (Al7Cu2(FeMn)/Al7Cu2Fe) phase. Al3(FeMn) phase is formed through a eutectic reaction approximately at 640 °C during solidification, possibly resulting from the phase selection and segregation of Fe in liquid Al. The presence of the Al3(FeMn) phase has been confirmed by both EBSD and TEM. It is also found that both β-Fe and Al6(FeMn) are possible to nucleate on Al3(FeMn), as confirmed by the calculated low planar disregistries. The possible solidification reactions have been established for 206-type cast alloy at 0.5%Fe. |
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