Studies on Tensile Fracture and Two Body Wear Behavior of Al/Si3N4-Al2O3 Nanocomposites Prepared by Powder Metallurgical Route

The tensile fracture and two body wear behavior of [Al/Si3N4/Al2O3](P) nanocomposites were examined in the present investigation. The nanocomposites were prepared by using aluminum powder as matrix and Al2O3, Si3N4, and mixed composition of Al2O3 and Si3N4 reinforcing particles with varying compositions of 1%, 2%, and 3% each through powder metallurgical (PM) technique. Tensile characteristics and two body wear behavior of pure and fabricated samples were examined by performing tensile and dry sliding tests, and their results were correlated with microstructure, fracture, and worn surface morphology using scanning electron microscopy. Results revealed the improved tensile strength (203.38 MPa), hardness (56.6 HV), and lowest wear rate (1.14 x 10-6 mm(3)/N-m at 5 N) of pure Al reinforced with 2 wt.% Si3N4 and Al2O3 (M-2) attributing the agglomeration, cluster formation, and better diffusion of nanoparticles in the matrix material as compared to all other sample conditions where porosity, inhomogeneity, and improper bonding were observed. On revealing the SEM fractographs, the failure mode of M-2 sample transformed into ductile failure mechanism with respect to other compositions where brittle and mix-mode fracture was observed to be prominent fracture mechanism.