Experimental investigation of the mechanical properties of AA7075/ ZrO2/Gr composite fabricated by friction-stir additive manufacturing

Purpose This study aims to improve the structural performance of AA 7075 aluminium alloy by reinforcing it with ZrO2 and graphene using friction stir additive manufacturing (FSAM). The goal is to enhance mechanical properties such as hardness, tensile strength and compressive strength through uniform dispersal of the reinforcements in the aluminium matrix. The study successfully achieved significant improvements in these properties, making the composite more suitable for real-world applications. Design/methodology/approach This study used FSAM to reinforce AA 7075 aluminium sheets with varying weight percentages of ZrO2 and graphene (Gr). A high-speed steel (HSS) tool with a triangular pin integrated the reinforcements into the aluminium matrix. Microstructural analysis confirmed uniform dispersal of the reinforcements, and mechanical tests showed significant improvements. The composite demonstrated a notable increase in hardness, tensile strength and compressive strength compared to the base material. Findings The study found that the AA 7075 composite reinforced with ZrO2 and graphene (Gr) achieved significant mechanical improvements. Microstructural analysis confirmed uniform dispersal of reinforcements. The composite with 4 Wt.-% ZrO2 and 6 Wt.-% Gr showed a 27.2% increase in hardness, 23.8% improvement in tensile strength and 18.5% increase in compressive strength, demonstrating the effectiveness of FSAM in enhancing material performance. Originality/value The study’s originality lies in using FSAM to reinforce AA 7075 aluminium alloy with ZrO2 and graphene (Gr), enhancing its mechanical properties. The innovative use of different reinforcement percentages and a HSS tool with a triangular pin ensures uniform dispefrsal, significantly improving hardness, tensile strength and compressive strength. This contributes to advancing the structural performance of aluminium alloys for practical applications.