Shipbuilding is an industry where the most stringent requirements are placed on materials. Ships and offshore platforms must withstand significant loads, temperature fluctuations, exposure to salt water and chemicals, and long service cycles. Under these conditions, steel remains the main structural material, ensuring the strength, durability and safety of ships.

Company ArtMetal (art-metal.com.ua) has experience supplying rolled metal and structural steel for the maritime industry. In this article, we'll take a detailed look at What steel is used in shipbuilding, its properties and main areas of application.

Why is steel so important for shipbuilding?

Steel has a unique combination of properties required for marine structures:

High strength and ductility
Allows to withstand heavy loads, wave impacts, wind and ice effects.
Durability
The service life of steel housings can exceed 25-30 years with proper operation and maintenance.
Possibility of welding and processing
Steel is easy to weld, cut, stamp, and heat treat, which is important in the production of complex structures.
Corrosion resistance (during processing)
With the help of alloying elements and protective coatings, the steel is resistant to salt water and aggressive environments.
Accessibility and cost-effectiveness
Steel remains more affordable than aluminum or composite materials, especially for larger vessels.

Types of steel used in shipbuilding

The choice of steel grade depends on the vessel's intended purpose, operating conditions, and strength requirements. The main types are:

1. Low-alloy structural steel

Application: hulls, decks, bulkheads, superstructures.
Specifications: High tensile and impact strength; good ductility; weldability.
Popular brands: St3, A36, S235JR (according to international standards).

Advantages: inexpensive, versatile, easy to process.
Restrictions: requires protective coatings to prevent corrosion in the marine environment.

2. High-strength marine steel

Application: The hull elements are resistant to impact loads and waves.
Specifications: increased strength, improved viscosity and impact toughness at low temperatures.
Examples: AH36, DH36, EH36 (IACS classification).

These steel grades can withstand extreme operating conditions, including ice loads and severe storms.

3. Corrosion-resistant and alloy steel

Application: deck equipment, tanks, pipelines, superstructure elements.
Specifications: The addition of chromium, nickel, and molybdenum increases resistance to salt water and chemical environments.
Brands: AISI 304, AISI 316 (for individual elements).

These steels are especially important in areas of constant contact with sea water, where the risk of corrosion is high.

4. Lightweight and high-strength alloys

They are used less frequently, but can be used in special ship components: outboard structures, elements of boats and yachts.
They combine high strength and reduced weight, which improves the efficiency and speed of the vessel.

Features of the use of steel in shipbuilding

Ship's hull
The most critical element, requiring a combination of strength and ductility. Low-alloy structural steel or AH36 marine steel are typically used.
Decks and superstructures
Strength and corrosion resistance are important here. Low-alloy and alloy steels with protective coatings are used.
Tanks and pipelines
Stainless and corrosion-resistant steels are used for fuel, water and chemical liquids.
Ice and Arctic vessels
Steels with high impact toughness at sub-zero temperatures are required - EH36 and similar grades.
Mechanisms and equipment
Steel alloys are used for cranes, pulleys, anchor systems and other critical components.

Steel protection technologies on marine vessels

To extend service life and reduce the risk of corrosion, the following are used:

Zinc and polymer coating
Primers, epoxy coatings, and polymer layers increase resistance to salt water.
Cathodic protection
Used for large objects, reduces electrochemical corrosion of the body.
Regular maintenance
Cleaning, hull inspection and repainting will extend the life of your vessel.

Advantages of steel in shipbuilding

high strength and reliability;
the ability to weld and manufacture complex structures;
Durability with proper protection;
economic accessibility;
compliance with international standards of classification societies (Lloyd's Register, DNV GL, Bureau Veritas).

Conclusion

Steel remains key material in shipbuilding Thanks to their combination of strength, ductility, and corrosion resistance, various steel grades allow for the design of hulls, superstructures, equipment, and mechanisms for ships operating in any conditions—from river vessels to icebreakers.

Company ArtMetal supplies high-quality rolled metal products for the maritime industry, ensuring the reliability and durability of ship structures. Selecting the right steel grade, protecting it, and properly processing it are key to the safety and efficiency of marine vessels.