Tribological behavior of AA7075 hybrid composites reinforced with Al2O3 and TiO2 particles

Abstract

The study investigates the wear behavior of AA7075 hybrid composites reinforced with varying percentages of Al2O3 andTiO2. The microstructure reveals a homogenous distribution of reinforcing particles in the aluminum alloy matrix, enhancedby the addition of K2TiF6 flux. The wear process parameters, including % reinforcement, applied load, temperature, slidingvelocity, and sliding distance, are systematically studied to understand their effects on wear resistance. The results reveala non-linear trend in wear rate with increasing % reinforcement, showing an optimal percentage for the lowest wear rate. Applied load initially improves wear resistance but can lead to increased wear rates beyond threshold limit. The wear ratedecreases initially with increasing temperature, indicating improved wear resistance, but increased at higher temperaturesdue to thermal softening effects. Sliding velocity and distance also significantly influence wear behavior, with lower wear ratesobserved at moderate velocities and distances due to the formation of protective layers. The addition of reinforcement reducesthe COF, the relationship between COF and wear rate is inversely proportional, with lower COF leading to lower wear rates. The presence of reinforcement stabilizes the COF at different sliding distances, indicating improved wear resistance. The wornsurface morphology indicates severe abrasion, micro-cutting, and plastic deformation, influenced by particle characteristicsand load.