Evaluation and Optimization of Tribological Properties of Al7055 Reinforced Stir Cast Nano Silicon Nitride Metal Matrix Composites Using Moora - Entropy Method

In this present work, the study of tribological characteristics on Al7055 reinforced with nano silicon nitride with different weight percentages. The bottom-pouring stir casting method was used to fabricate Al7055/ Si ₃ N ₄ Nano composite.The nano Si ₃ N ₄ particles are taken in different weight fractions such as 3 wt. %, 6 wt. %, and 9 wt. %, also the size of reinforced particles varied from 30 nm to 90 nm in the step of 30 nm. The results show that the maximum hardness value obtained is 139.8 VHN for 9 wt % Si ₃ N ₄ of 30 nm size. SEM image shows a cluster formation for 9 wt % composites due to the inclusion of hard ceramic reinforcement of nano-sized particles. Moora entropy method was used to optimize wear parameters. From the wear test it can be concluded that the wear rate increased with normal load, meanwhile wear resistance significantly improved with the addition of Si ₃ N ₄ particles, ANOVA results shows that normal load and weight percent of reinforcement are the dominant parameters on wear, and their contributions are 27.72% and 13.80%, respectively.