Influence mechanisms of Cu or Fe on the microstructures and tensile properties at 350 °C of network AlNp reinforced Al composites

In this work, the influences of alloying elements like Cu and Fe on the microstructures and tensile properties (at 350 °C) of network AlNp reinforce Al composites have been studied. After alloying element introduction, Cu atoms tend to segregate on the AlNp/Al interface, while Fe atoms not. Meanwhile, the α-Al grains show a 〈111〉Al fiber texture in the AlNp reinforced Al composites with Cu addition and a {110}Al 〈111〉 Al texture in the AlNp reinforced Al composites containing Fe, which are different from the random α-Al orientations in the AlNp/Al composites without element addition. The tensile properties of AlNp/Al composites containing alloying elements at 350 °C are affected by the preferred orientations of α-Al grains and the changes of dislocation density. The elongation of the composites containing Cu increased remarkably from 3.5% to 14% with just little tensile strength sacrifice at 350 °C. Nevertheless, after Fe incorporation, the tensile strength is increased to 140 MPa, coupled with the elongation of 7% at 350 °C.