Effect of Fe Content on the Microstructure and Properties of Hot-extruded 6061 Aluminum Alloy

Abstract The effect of Fe content on the microstructure and properties of Hot-extruded 6061 aluminum alloy was investigated. The results show that the recrystallization process can be effectively inhibited by increasing Fe content appropriately, and consequently affect the grain refinement. After hot extrusion, the iron-rich phase in 6061 aluminum alloy was broken, and fragmented phases are distributed along extrusion direction. After T4 and T6 heat treatment, a large amount of fragmented α-Al(FeMnCr)Si and Mg2Si phases are distributed for the sample with 0.3% content of Fe element. After T6 treatment, the yield strength, tensile strength and elongation of the 0.3%Fe-contenting sample are 298.95MPa, 337.43MPa and 17.88%, respectively. Compared with the hot extruded sample, its tensile strength is significantly increased, about 74.1%, but without noticeable sacrifice of its elongation.