Document Type: Research Paper
Department of Materials Science and Engineering, School of Engineering, Shiraz University, Shiraz, Iran.
Department of Materials Science and Engineering, Shahid Bahonar University of Kerman, Kerman, Iran.
Excellent mechanical properties and fatigue performance of Al/Al2O3 metal-based nanocomposites caused to introduce this material as a good candidate for various applications. In this regard, the preparation and characterization of this composite can be considered as a hot issue for research. The study was carried out in several steps including: (i) preparation of Al/Al2O3 metal-based nanocomposites at various Al2O3 content as reinforcement (4, 6 and 8 wt.%) using wet attrition milling; (ii) hot forward extrusion process of prepared samples; (iii) determination of mechanical properties of prepared composite by tensile test; (iv) usage of rotating-bending fatigue test for determination of the fatigue performance of prepared composite and (v) analysis of the fracture surfaces of fatigue tests specimens to determine the mechanism/s of failure based on scanning electron microscope analysis. The results showed that the presence of Al2O3 nanoparticles up to 6 wt.% enhanced the fatigue strength of Al/Al2O3 nanocomposites while the higher amount of reinforcement has a detrimental effect on the fatigue strength. Also, the statistical nature of fatigue data confirmed the higher coherency as well as homogeneity of prepared composites by 6 wt.% of reinforcement. The EDX spectrum confirmed the presence of Al2O3 at the origin of crack. As a consequence, the most probable mechanisms for crack initiation through the cyclic loading can be considered as the fracture and/or detachment of reinforcement particles.