Investigations on mechanical and wear behavior of nano Al2O3 particulates reinforced AA7475 alloy composites

Abstract

In the present investigation synthesis, microstructure, mechanical and wear behavior of 5 weight percentage of nano Al2O3 particulate reinforced AA7475 alloy composites has been reported. AA7475 matrix composite containing nano Al2O3 were fabricated by conventional stir casting method. The microstructures of the composites were examined by scanning electron microscopy. Further, mechanical and wear behavior of as cast AA7475 alloy and AA7475 - 5 wt. % nano Al2O3 composites were studied. Mechanical properties like hardness, ultimate, yield strength and percentage elongation were evaluated as per ASTM standards. Pin on disc apparatus was used to conduct the dry sliding wear tests. The experiments were conducted by varying loads and constant sliding speed of 300rpm for sliding distance of 4000m. Microstructural observation revealed the uniform distribution of particles in the AA7475 alloy matrix. From the analysis, it was found that the hardness, ultimate tensile strength and yield strength of composites were increased due to addition of nano Al2O3 particle in the AA7475 alloy matrix. Percentage elongation of the composite decreased in 5 wt. % nano Al2O3 reinforced composites. Further, the volumetric wear loss was found to increase with the load and sliding distance for all materials. Worn surface analysis made by using scanning electron micrographs to know the various mechanisms involved in the wear process.