Mechanical characterization and reciprocating wear analysis of AA 7075 hybrid metal matrix composite reinforced with B 4 C and BFS

High strength 7XXX series aluminum alloys find wide use in aerospace, marine, military and defense. Nevertheless, these applications require improved wear resistance, which is lagging in the case of AA 7075 alloy. This study aims to investigate the effects of boron carbide and blast furnace slag reinforcement on the mechanical properties and reciprocating wear performance of AA 7075 hybrid metal matrix composites under different wear environments. Casting samples with varying weight percentages of boron carbide and blast furnace slag were prepared for this analysis. Reciprocating wear tests were conducted under dry, lubricated and elevated temperature conditions with a fixed applied load of 40 N. The wear profile was analyzed using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, and various mechanical properties, such as hardness, tensile strength, and impact strength were also evaluated for the composites. The composite with highest reinforcement content (15 wt.% B 4 C + 8 wt.% BFS) yields superior wear resistance, marked by 46 % increase in ultimate tensile strength (275.34 MPa) and a 48 % rise in hardness (189.43 HV) relative to an unreinforced composite (187.56 MPa & 128.87 HV). These improvements underscore the role of reinforcement in enhancing mechanical performance. The study uniquely highlights the effectiveness of boron carbide and blast furnace slag as a hybrid reinforcement system in significantly overcoming the wear limitations of AA 7075, providing a practical and novel solution to improve service life of components in high performance applications.