The growing demand for materials with exceptional corrosion resistance and mechanical properties in the aerospace and ocean industries has led to increased research interest in versatile alloys like nickel–aluminum bronze (NAB). NABs exhibit excellent corrosion performance due to the formation of a protective, duplex corrosion product film on the surface, which is largely influenced by their complex microstructure. While NABs are typically produced as cast or wrought products, the emergence of additive manufacturing (AM) technologies has enabled 3D printing of near-net-shape NABs with intricate geometries. This paper provides a critical review of the corrosion properties, passivity, and microstructural characteristics of conventionally produced and AMed NAB alloys, as well as the fundamental mechanisms governing their corrosion behavior under varying conditions. Additionally, it highlights the current research gap and unprecedented challenges associated with the corrosion behavior of traditional and AMed NABs.

Ferrous alloys, particularly steels, form a specialized class of metallic materials extensively employed in industrial sectors to combat deterioration and failures caused by wear. Despite their commendable mechanical properties, steels are not immune to wear-induced degradation. In this context, surface nanocrystallization (SNC) technologies have carved a distinct niche for themselves by enabling the nanostructuring of the surface layer (with grain sizes < 100 nm). This process enhances overall mechanical properties to a level desirable for wear resistance while preserving the chemical composition. Existing literature has consistently highlighted the efficacy of various SNC methods in improving the wear resistance of ferrous alloys, positioning SNC as a promising tool to extend materials’ service life in practical applications. This review provides a comprehensive examination of the SNC techniques employed in surface treatment of ferrous alloys and their impact on wear behavior. We delved into the underlying mechanisms governing wear in SNC-treated Fe-based alloys and concluded with a discussion on current challenges and future perspectives in this evolving field.