The primary role of AQ51 is to serve as a cost-effective structural material for non-critical ship parts, where high strength and basic corrosion resistance are required without the need for extreme low-temperature performance. Its advantages include good weldability and formability—AQ51 can be easily welded using standard marine welding techniques without extensive pre-heat treatment, reducing manufacturing time and costs. It also has inherent corrosion resistance due to its chemical composition (typically containing 0.18% max carbon, 1.60% max manganese, and trace elements like copper), which helps withstand exposure to seawater and marine atmospheres.
In terms of application scope, AQ51 is widely used in the construction of coastal ships, inland waterway vessels, and small to medium-sized cargo ships. Common applications include hull framing, deck plating, bulkheads, and superstructure components that are not exposed to extremely low temperatures or heavy dynamic loads. It is also suitable for offshore structures like jetties and small oil platforms, where the operating environment is relatively mild. Additionally, AQ51 is used in the repair and maintenance of older ships, as it matches the strength requirements of many legacy marine structures.