Tensile and Dry Sliding Wear Properties of Compo-Cast SiO2 Coated ABOw/ Al-319 Composites

Abstract

Al-319 matrix composite reinforced by SiO2-coated Al18B4O33 (ABOw) whiskers with different percentages (2.5,5,7.5,10%) were fabricated by a compo-casting technique. SiO2 coating of aluminium borate whiskers was prepared by hydrolysis route in our previous work. The effect of coating and whisker percentage content matrix microstructures, mechanical and tribological properties and fracture mechanisms of the composites were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS) and transmission electron microscopy (TEM). Scanning probe microscopy (SPM) was used for worn surface analysis of the composite. The mechanical results showed that adding SiO2-coated 7.5% ABO whiskers in Al-319 led to an improvement in yield strength, ultimate tensile strength, dry sliding wear and hardness. The reason is that the MgAl2O4 interfacial product resulting from the reaction between the SiO2 coating, and the liquid Al can enhance the interfacial bonding strength and increase the load transfer from the matrix to the reinforcement, which leads to higher wear properties composite. © 2023, The Author(s), under exclusive licence to Springer Nature B.V.