SOLIDIFICATION CHARACTERISTICS OF Fe-RICH INTERMETALLICS AND ITS EFFECT ON MECHANICAL PROPERTIES OF SQUEEZE CAST Al-5.0Cu-0.6Mn ALLOY

摘要

The development of high performance Al-Cu based alloys generally depends on the strict control of the Fe content. With the increasing use of recycled aluminum alloys, it is necessary to extend the tolerance of Fe content for the purpose of low cost, energy saving and environment protection. In this paper, the solidification characteristics of Fe-rich intermetallics and its effect on mechanical properties of squeeze cast Al-5.0Cu-0.6Mn alloy with Fe content up to 1.5 wt% have been investigated. The full solidification sequence of the squeeze cast alloys with different Fe contents has been established. The applied pressure is favor to the formation of Chinese script Fe-rich intermetallics α-Fe / Al_6(FeMn) and prevents the precipitate of needle-like P-Fe / Al_3(FeMn). The elongation of the alloys decreases gradually with the increase of Fe content and there is a maximum ultimate tensile strength and yield strength for the alloys with 0.5 wt% Fe.