Investigation on Wear Characteristics of Oxide-Added Cast 7075 Aluminum Alloy

Aluminum 7075 alloy has excellent mechanical properties and exhibits good ductility, strength, toughness, and fatigue resistance. The addition of oxide additives to cast Al7075 has also enhanced tribological properties apart from these properties. In this study, the tribological properties of cast Al7075 with the addition of 2.5% zirconium oxide (Zirconia) and titanium oxide (Titania), produced in a resistance melting furnace followed by die casting, were investigated. The wear test is conducted using a pin-on-disc wear testing machine, as specified by ASTM G99. The comparison is based on two independent process variables: a fixed sliding distance of 1000 m for all samples and applied load variations are 10, 20, 30, and 50 N with 500, 700, and 1000 revolution speeds. Using a scanning electron microscope (SEM), the wear surface morphology of the samples was analyzed, and the wear test results were compared. Further, it was found that oxides added samples showed less wear loss compared to as-cast Al7075 samples. The abrasion mechanism for as-cast Al7075 samples is identified as ploughing and deep wear tracks, while for Al7075 samples with Zirconia and Titania addition, it is characterized by delamination and shallow wear marks that show less wear.