In this research work, ultrasonic cavitation assisted casting process was used to fabricate the aluminum alloy-nano boron carbide metal matrix nanocomposites. The optical microscopy results revealed the refined matrix grains in the microstructure of the aluminum alloy-nano boron carbide composites. Boron carbide nanoparticles were uniformly distributed in the aluminum alloy matrix, which can be confirmed by scanning electron microscopic images. The aluminum alloy-nano boron carbide composites show increased dislocation density, compared to the monolithic alloys, which was observed from the transmission electron microscopic images. The addition of nano boron carbide in aluminum alloy matrix, significantly improved its hardness and tensile strength, while the good ductility and impact resistance of the aluminum alloy was almost retained. The results of the dry sliding wear pin-on-disc tests showed improved wear resistance properties of aluminum alloy-nano boron carbide composites compared to the monolithic aluminum alloys.
In this investigation, the abrasive wear resistance of Al/ (B4C+SiC) hybrid nanocomposites was tested against hard SiC abrasive sheets and compared to those of unreinforced Al alloy. Three loadings of nano-SiC (0.5, 1.0, and 1.5 Wt. %) and one loading of nano-B4C (0.5 Wt. %) were mixed with an aluminium alloy to produce the aluminium hybrid nanocomposites using an ultrasonication assisted casting method. Scanning electron microscopy showed a uniform distribution of nanoparticles in the Al alloy. Transmission electron microscopy indicated an increase in the dislocation density of nanocomposites compared to monolithic Al. The abrasive wear experiments were conducted on a Pin-on-Disc tribometer using pins of 9 mm diameter and 15 mm height under dry sliding conditions at room temperature. The wear rate in terms of wear volume per unit weight was calculated for both unreinforced alloy and hybrid nanocomposites. It was observed that Al hybrid nanocomposites showed superior wear resistance properties compared to the unreinforced sample. The nanocomposite with 1.5 Wt.% nano-SiC and 0.5 Wt.% nano-B4C possessed better wear resistance properties compared to the other composites tested in this work. The worn out surface of the Al alloy and its hybrid nanocomposites imply that the wear mechanism is through plowing action on the surface by SiC abrading particulates. The nanocomposite with 1.5 Wt.% SiC and 0.5 Wt.% B4C showed 88.32 % increase in wear resistance compared to the monolithic Al. This combination of material can be selected for abrasive wear resistance applications.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.