As a typical non-heat-treatable Al-Mg aluminum alloy, 5083 aluminum alloy features excellent weldability, formability and superior marine environmental adaptability. It has been widely adopted as a core structural material for shipbuilding, offshore platforms and marine engineering equipment. The seawater-air interface of marine environments, including the splash zone, waterline (tidal fluctuation) zone and full immersion zone, suffers from combined adverse factors such as alternating wet and dry conditions, salt spray erosion, microbial attachment and wave scouring, which make it a high-risk area for corrosion failure of aluminum alloys. Based on a 2.5-year in-situ marine exposure test conducted in the Bohai Sea, this article systematically investigates the corrosion behavior and mechanisms of long-sized 5083 aluminum alloy specimens in different regions of the seawater-air interface. Combining macroscopic characterization, microscopic analysis and electrochemical tests, this study reveals the regulatory effect of interfacial environmental factors on the corrosion process. The research outcomes provide solid experimental data and theoretical support for corrosion protection design and service life evaluation of 5083 aluminum alloy applied in marine engineering projects.

3003 aluminum alloy is a high-performance medium-strength aluminum alloy, renowned for its excellent atmospheric corrosion resistance, superior weldability, and good cold formability. Compared with 1000 series alloys, it boasts better mechanical properties, especially in elevated temperature environments, making it a versatile choice for multiple industries.

7075 is a premium high‑strength aluminum alloy from the 7xxx Zn‑Mg‑Cu series, widely recognized as aircraft aluminum for exceptional strength‑to‑weight ratio, fatigue resistance, and structural stability. It is the preferred material for aerospace, defense, automotive, and high‑performance engineering applications.

Aluminum alloys are widely used in manufacturing due to their outstanding advantages such as light weight, strong corrosion resistance, and high specific strength. In the shipbuilding industry, the lightweight properties of aluminum alloys can significantly reduce the ship's hull weight, lower the center of gravity, and improve corrosion resistance, thereby optimizing ship stability and operational economy, making it one of the ideal materials for lightweight ship design. However, the difficulty in welding aluminum alloys and their lower strength compared to traditional marine carbon steel have limited their large-scale application in ocean-going vessels.

6061 aluminum alloy is one of the most widely used heat-treatable aluminum alloys in the world, valued for its outstanding mechanical properties, corrosion resistance, machinability, and weldability. When supplied in T5 and T6 tempers, 6061 aluminum bar exhibits consistent performance for structural, manufacturing, and engineering applications across industries including automotive, automation, aerospace, machinery, and electronics.

This article compares 6061 and 5052 aluminum alloy sheets in three core dimensions: mechanical strength, weldability, and corrosion resistance. It clearly explains their performance differences, typical application scenarios, and provides straightforward selection advice for fabricators, engineers, distributors and procurement teams.