Preparation and investigation of mechanical behavior and characterization of AA7475/ZrO2/Gr hybrid MMC

Abstract

In this study, the influence of zirconium dioxide (ZrO2) and graphite (Gr) on the mechanical behavior and characterization of Hybrid metal matrix composites (HMMCs) is investigated. By using the stir casting method, the samples are prepared with aluminum alloy (AA7475) as matrix and 2, 3, and 4 weight percentages (wt%) of zirconium dioxide (ZrO2) and graphite (Gr) as reinforcements. The synthesized composites were subjected to microstructural, density, porosity, yield strength (YS), ultimate tensile strength (UTS), and hardness were examined. Microstructural characteristics were examined using scanning electron microscopy (SEM). The XRD pattern indicated the presence of the ZrO2 and Gr phases in HMM composites. By conducting a corrosion resistance test, the rate of corrosion for the HMMCs was determined. Furthermore, the Tafel plot curve was employed to probe the level of corrosion resistance. With an increase in ZrO2 the corrosion resistance increases whereas decline in ductility is noted. The HMMCs 3 sample exhibit superior physical and mechanical properties when compared to other HMMCs and base matrix. Tensile fractography was carried out to determine the various fracture mechanisms.