Evaluation of Microstructure and Mechanical Properties of Al-Zn-Mg-Cu Alloy Repaired via Additive Friction Stir Deposition

Abstract A novel solid-state additive manufacturing (AM) process, friction stir deposition (AFS-D), provides a new pathway for additively repairing damaged nonweldable aerospace materials that are susceptible to induced thermal gradients within the microstructure. In this work, we quantify microstructural evolution and mechanical performance of an repaired AA7075-T651 (Al-Zn-Mg-Cu) via AFS-D process. To evaluate process high strength aluminum alloys, technique was used fill linear groove machined into plate. After plate with subjected standard T6 heat treatment. The results study show heat-treated repair did not exhibit any significant grain growth demonstrated increase in average Vickers hardness compared wrought 7075-T651 control. Tensile fatigue behavior investigated exhibited wrought-like tensile properties yield stress (YS) ultimate stress; however, had scatter elongation failure. Additionally, mean repairs displayed reduction cycles failure Lastly, microstructure-sensitive life model elucidate process-structure-property mechanism relations AA7075.