INVESTIGATION OF WEAR BEHAVIOR OF AL6061 BASED HYBRID COMPOSITE USING STATISTICAL TECHNIQUES

Abstract

Because of their exceptional strength-to-weight ratio, outstanding thermal conductivity, and resistance to corrosion, AMCs   have become a viable material for lightweight structural and tribological applications. Hybrid AMCs reinforced with different reinforcements have drawn a lot of interest recently because they allow for cost and weight optimization while providing a balanced improvement in mechanical and tribological qualities. In this regard, the current study focuses on the creation and methodical characterization of a hybrid metal matrix composite based on Al6061 that is reinforced with ceramic particles of titanium dioxide (TiO₂) and coconut shell ash (CSA), a bio-filler obtained from agricultural waste.

The primary objective of this work is to investigate the synergistic influence of ceramic and bio-based reinforcements on the mechanical and tribological behavior of Al6061 alloy. The use of TiO₂ as a hard ceramic reinforcement is intended to enhance hardness, strength, and wear resistance, while CSA is incorporated to reduce density, improve sustainability, and contribute to tribological performance. Hybrid AMCs were fabricated using the stir casting method by varying the TiO₂ content while maintaining a constant CSA fraction. The fabricated composites were subjected to comprehensive microstructural, and tribological characterization. Dry sliding wear behavior was evaluated using a pin-on-disc tribometer under varying load, sliding speed, and sliding distance conditions. A Taguchi L16 orthogonal array was employed to design the experiments, followed by analysis of variance (ANOVA) and Response Surface Methodology (RSM) to identify the relative significance of wear parameters. The statistical analysis identified that reinforcement is the primary factor influencing wear behavior, where hybrid composites incorporating filler particles exhibit improved wear resistance. while load and speed contributed to increased wear through mechanical and thermal effects. Increased hardness and the combined effect of CSA and TiO₂ reinforcements were highly associated with the hybrid composites' enhanced wear resistance. The effective utilization of agro-waste–derived CSA alongside ceramic reinforcement not only improves tribological performance but also contributes to sustainable and cost-effective composite development, making the material a promising candidate for wear-resistant engineering applications.