A Guide to Understanding Marine Grade Aluminum 

The corrosive nature of water and saltwater dictates the use of special materials for shipbuilding, off-shore drilling platforms, and more. Due to its many beneficial properties, marine-grade aluminum is eminently suitable for building seafaring vessels and structures, as well as the machinery and components used within them.

What is Marine-Grade Aluminum?

Even though pure aluminum has a high natural resistance to corrosion compared to many other metals, the constant exposure to water and moisture in marine applications warrants additional protection. When alloyed with other metals like magnesium, aluminum develops an even higher level of corrosion resistance that can tolerate constant contact with water and saltwater. These specially treated aluminum alloys are known as marine-grade aluminum.

What are the Benefits of Using Aluminum in Marine Applications?

Marine-grade aluminum is specifically developed to make it ideal for use in marine environments. As such, it possesses a number of properties required in these applications. Some of these properties include:

• Superior corrosion resistance
• Lightweight with a high strength-to-weight ratio
• Compatibility with a variety of fabrication processes
• Wide availability in sheets, extrusions, and plates

Properties of Aluminum for Marine Applications

There are many grades of marine aluminum, each differing slightly in its properties due to the alloy materials that are included.

Continental Steel supplies several grades of marine aluminum in a variety of stock forms, including plate, sheet, coil, pipe, tube, bars, and extrusions We can also provide them with varying degrees of temper. The grades we can provide include: 

• 5083. 5083 marine-grade aluminum is ideal for applications that need superlative corrosion resistance in hostile environments. 5083 is the strongest non-heat treatable aluminum alloy and maintains its strength even after welding.
• 5086. This alloy is highly conductive with superior corrosion resistance. 5086 can be strengthened through strain hardening and cold working until it is even stronger than in 5083. Though compatible with multiple welding methods, electric arc welding is preferred for this alloy.
• 5454. The beneficial properties of 5454 include high strength, superior corrosion resistance, and good formability and weldability. 
• 5456. Widely used for structural applications, 5456 is well-suited to the extrusion process. It is also amenable to forming operations like rolling and forging. 5456 can be made stronger through cold working, but the process reduces its ductility.
• 5754. Its superior resistance to corrosion makes 5754 very suitable for the marine industry and other industrial applications possessing corrosive operating environments. It is also suitable for flooring applications due to its high strength.

Aluminum Products for Marine Applications

Marine aluminum is used to make a wide variety of marine products. Two of these include honeycomb panels and metal powder. 

Honeycomb panels are composite products inspired by the structure of honeycombs in bee colonies. A honeycomb panel consists of a core layer of hexagonal honeycomb fabricated with aluminum. The core is sandwiched between two aluminum plates glued to either side. This structure can be fabricated with various thicknesses. 

Honeycomb panels have the following beneficial properties:

1. Low weight
2. High rigidity, strength, and vibration damping
3. High resistance to impacts
4. Good insulation from heat and sound
5. Good pliability

Since the honeycomb panel requires a smaller quantity of aluminum than a solid sheet of comparable mechanical properties and thickness, it is more cost-effective than aluminum panels. It’s lighter weight also saves on shipping costs for bulk orders. Like all aluminum, honeycomb panels can be infinitely recycled.

Aluminum metal powders are used in a variety of industries, including the marine industry. These fine particles of aluminum are used in many manufacturing techniques, such as aluminum injection molding, surface coating, and additive manufacturing.

Marine Grade Aluminum From Continental Steel

Continental Steel is an ISO 9001:2015-certified supplier and distributor of high-quality specialty metals, including marine aluminum. We provide these value-added services for all grades of aluminum to facilitate one-stop shopping for our customers:

• Anodizing
• Chemical milling
• Deep hole drilling
• Grinding
• Perforating
• Polishing
• Rigidizing
• Trepanning

Please contact us or request a quote for more information about our marine-grade aluminum supply and capabilities.