Fatigue and Fretting Wear Behaviors of Friction Stir Powder Additive-Manufactured AA7075 Aluminum Alloy

Abstract

Aluminum 7075 alloy is widely used in aerospace and automotive industries due to its high strength-to-weight ratio. However, traditional manufacturing processes for this alloy can lead to various issues, including porosity and poor fatigue properties. Friction stir powder additive manufacturing (FSPAM) is an emerging additive manufacturing technique promising to improve the corrosion resistance, fatigue behavior and fretting wear of AA7075 aluminum alloys. This work investigates the microstructure, fretting wear behavior, tensile strength, and fatigue behavior of AA7075 aluminum alloys fabricated using FSPAM. The microstructure revealed a distinct difference in grain size between the two materials. Notably, the grain size in the FSPAM AA7075 was much finer than in the as-casted AA7075 aluminum alloy. The investigation into fretting wear under applied loads of 5, 10, and 15N revealed a consistent reduction in the coefficient of friction (COF) with load increases. The microhardness, tensile strength and fatigue strength of FSPAM AA7075 aluminum alloy have increased significantly. This finding highlights the impact of the strength of AA7075 aluminum alloy through FSPAM. © ASM International 2025.