The aim of this study was to produce bulk Al-10 wt.%Al 3 V And Al-10 wt.%(Al 3 V-Al 2 O 3 ) nanocomposites and to investigate the high temperature properties of samples. The structural characteristic of powder particles and consolidated samples were studied by X-ray diffraction (XRD), scaning electron microscopy (SEM), differential thermal analysis (DTA), and transmission electron microscopy (TEM). Mechanical properties and wear behavior of extruded samples at room and high temperature was evaluated. In order to study the creep behavior of samples, creep tests were performed at 250-350°C. The results showed that MA of Al 75 V 25 powder mixture leads to formation of amorphous phase after 40 h. After heat treatment of mechanically alloyed powder at 600°C for 1h, Al 3 V was formed. Al 3 V -Al 2 O 3 reinforcements was produced through a mechanochemical reaction of Al and V 2 O 5 . In order to produce nanocomposite powders, Al 3 V and Al 3 V-Al 2 O 3 reinforcements powders were added to the pure Al powders and milled for 5h. The prepared nanocomposite powders were consolidated by hot extrusion. The average Al grains in the as milled powder was measured to be 40 nm which increased to 50 nm after hot extrusion. The result showed that Al-10 wt.%Al 3 V And Al-10 wt.%(Al 3 V-Al 2 O 3 ) nanocomposites have tensile strength of 209 and 226 MPa, repectively. In addition, mechanical properties at high temperatures showed no drastical decrease up to 300°C. The creep test showed significant curvature in plots of the minimum creep rate vs stress, leading to high values for the apparent stress exponent and the apparent activation energy for creep. By introducing a threshold stress into the analysis, it was demonstrated that the true stress exponent, n, was close to 5 which suggests that the creep is controlled by a dislocation climb process. The results of wear test showed a lower wear rate for nanocomposies in contrast to the nanostructure pure Al. Dominate wear mechanism of nanocomposites was recognized to be formation of mechanically mixed layer (MML) on the worn surfaces. Comparison of wear behavior of the Al-10 wt.%Al 3 V and Al-10 wt.%(Al 3 V-Al 2 O 3 ) samples showed that Al-10 wt.%Al 3 V sample at different temperatures and for different loads has less wear rate than the Al-10 wt.%(Al 3 V-Al 2 O 3 ) sample. due to the weaker bond strength between Al 2 O 3 particles and aluminum matrix. Keywords: Aluminium matrix nanocomposite, Mechanical alloying, Hot extrusion, Creep, Wear.
