Characterization and Property Analysis of Heat-treated Functionally Graded Al8Si3Cu Alloy and TiC reinforced Composite

Abstract

Functionally graded (FG) Al8Si3Cu alloy and 8 wt% titanium carbide (TiC) reinforced composite (∅out100 × ∅56in × 100 mm) was fabricated through horizontal centrifugal casting, followed by T6 heat treatment. Metallographic analysis confirmed fine grain structure at FG alloy outer layers, whereas heat-treated alloy displayed spheroidised eutectic silicon. Gradient microstructure was observed for FG composite. Enhanced hardness for outer layer (10.31%) and tensile strength for outer zone (58.71%) were observed for heat-treated Al8Si3Cu/TiC composite owing to the high concentration of spheroidised eutectic Si and TiC particles, compared to as-cast composite. Linear reciprocating wear analysis performed on as-cast, heat-treated alloy and composite, respectively, at varying load (10–40 N) and sliding distance (500–2000 m) confirmed increasing wear rate, with heat-treated composite having superior wear resistance. Delamination wear was the predominant wear mechanism influencing wear behaviour of heat-treated composite. The alloy and composite were characterized using X-ray diffraction (XRD), energy dispersive spectrometry (EDS), optical microscopy (OM) and scanning electron microscopy (SEM).