Impact Resistance and Fracture Surface of Al6061 Hybrid Composites Reinforced by Fly Ash and Calcium Oxide

Abstract

Phase formation, impact resistance, and fracture surface were investigated in unreinforced Al6061, Al6061-5wt% fly ash and Al6061 hybrid composites containing 5wt% fly ash and 1,3 wt% CaO. The Al6061 composites were fabricated the stir casting process. The XRD patterns reveal the formation of second phases (MgAl2O4, CaAl4O7 and MgSiO3), which were found in the Al6061 hybrid composites. The average grain size of Al6061 hybrid composite are much smaller than that of unreinforced Al6061.The impact resistance was enhanced by approximately 67% in Al6061 hybrid composite as compared to unreinforced Al6061 alloy. Brittle fracture indicting brittle fracture was observed in unreinforced Al6061 alloy while evidence of a mixture of brittle and ductile fracture was found in the Al6061 hybrid composites.