Effect of Al<sub>2</sub>O<sub>3</sub> reinforcement nanoparticles on the tribological behaviour and mechanical properties of Al6061 alloy
Huda A. Al-Salihi, Hadia Kadhim Judran
Abstract
The goals of this investigation are the optimization and characterization of Al6061/Al<sub>2</sub>O<sub>3</sub> nanocomposite, which was synthesized by stir casting technique. Different concentrations of Al<sub>2</sub>O<sub>3</sub> nanoparticles as 5, 10, and 15 wt% with an average particle size of 40 nm were examined. The alumina nanoparticles were critically refined and distributed homogeneously in the Al6061 matrix. The microstructure of Al6061/Al<sub>2</sub>O<sub>3</sub> nanocomposite was observed by using scanning electron microscopy. The mechanical properties (tensile, hardness, and ductility) and tribological properties (wear and coefficient of friction) of Al6061/Al<sub>2</sub>O<sub>3</sub> nanocomposites were inspected. The experimental results revealed that there was a significant enhancement in the mechanical properties since it was observed that the yield tensile strength (YTS) increased from 52 to 69 MPa and ultimate tensile strength (UTS) increased from 122 to 158 MPa. The hardness test also showed an enhancement from 28 to 38 BHN at 10 wt% of alumina. The improvement ratios were observed at 32.69%, 29.51%, and 35.71%, respectively. Further, it was found that the incorporation of nano reinforcement can effectively improve the wear rate. It was observed 0.62 × 10<sup>-3</sup> (mm<sup>3</sup>/m) at 40 N of 10 wt% Al<sub>2</sub>O<sub>3</sub> nanoparticles comparison with 1.4 × 10<sup>-3</sup> (mm<sup>3</sup>/m) at the same load of the Al6061 alloy.