Experimental Investigations on the Development of Hybrid Metal Matrix Composite of Al7075 on Microstructural, Mechanical, and Dry Sliding Aspects

This research work aims to synthesize a hybrid Al7075 metal matrix composite reinforced with sustainable and synthetic reinforcement. With the employment of an ultrasonic transducer, two-stage stir casting is used to synthesize composite materials. The prepared samples were machined and polished for mechanical, tribological, and microstructural characterization. Optical microscopy and field emission scanning electron microscopy with elemental mapping were used to analyze the microstructure of the composite material. The microstructural examination revealed the homogeneous dispersion of reinforcement particles throughout the matrix. With the incorporation of reinforcement, the synthesized composite's compressive strength and micro-hardness were both increased, and the highest values were found to be 569.172 MPa and 178.86 HV, respectively, in one of the samples (B3 sample) as compared to as-cast Al7075 alloy. Tribological examination of composite samples shows that wear-rate enhances with an increase in the content of reinforcement. The wear resistance of sample B3 is highest among all prepared composite samples. Wear debris, grooves, micro-cracks, and small pits were observed on the worn-out surfaces of the samples by field emission scanning electron microscope analysis.