Effect of Heat Treatment on Mechanical Properties of an Aluminum Alloy and Aluminum Alloy Composite: A Comparative Study

The primary objective of this paper is to present and discuss the appropriateness of using the stir casting process as a viable approach for the fabrication of an in situ aluminum alloy-based metal matrix composite (MMC). The exothermic chemical reaction that occurs between the K₂TiF₆ and KBF₄ salts is responsible for the formation and presence of the reinforcing titanium diboride (TiB₂) particles in the melted aluminum–copper alloy. Presence of these particles exerts an influence on hardness, tensile strength, and even ductility of the engineered composite material. With the help of X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM), both the chosen aluminum alloy and the synthesized aluminum alloy composite material were characterized to facilitate a better understanding of the intrinsic morphological details and/or intrinsic features to include the size, morphology, and distribution of the TiB₂ reinforcement in the aluminum alloy metal matrix. For purposes of enhancing the mechanical properties of the chosen Al-4.5 pct. Cu alloy and the Al-4.5 wt.pct Cu/xTiB₂ composite a T6 heat treatment sequence was used and test results of the heat treated alloy compared with results obtained for the as-cast counterpart.