On a Steady Course
Aluminium in Shipbuilding
Shipbuilding has been undergoing continuous transformation for years. New operating profiles and rising efficiency requirements place increasingly demanding expectations on design and material selection. Aluminium has played a decisive role in this development: what once began as a lightweight option has evolved into a key material for many maritime applications. At the same time, the perspective on the material itself has sharpened. Modern shipbuilding is no longer just about weight advantages or good weldability. What truly matters is how reliably material properties can be ensured over long service lives, changing loads, and international project requirements.
AMAG Marine Certifications
- DNV
- Bureau Veritas (BV)
- ABS
- Lloyd’s Register (LR)
- RINA
AMAG offers marine products with various combinations of certifications.
Proven alloys for one of the harshest environments in the world
The marine environment is rightly considered one of the most demanding operating conditions for metallic materials. Constant moisture, salt, temperature fluctuations, and mechanical loads impose strict requirements on material selection and processing. For this reason, magnesium containing aluminium alloys of the 5xxx series have proven themselves in shipbuilding for many years.In the marine sector, AMAG focuses on the alloys EN AW 5083 and EN AW 5086 in tempers H111, H116, and H321, supplied as sheets and plates. These materials combine good mechanical properties with excellent corrosion resistance and processing characteristics that meet the demands of shipbuilding, especially in welding. Even for established alloys, however, it is not only chemical composition that determines suitability for marine use. What truly matters is how consistently and reproducibly the desired properties can be achieved.
Corrosion resistance is the result of controlled processes
Corrosion in shipbuilding is rarely a uniform, surface wide phenomenon. Local effects are usually the critical factor: at grain boundaries, in heat affected zones of weld seams, or in areas with prior mechanical strain. This makes targeted process control during the production of the semi-finished material particularly important.AMAG achieves the corrosion resistance required for marine applications, both against intergranular corrosion and exfoliation corrosion through precise control of alloying elements in the slab and specially coordinated heat treatment processes. This approach ensures not only compliance with standard values, but also that the material properties prove reliable under real operating conditions. For shipyards and designers, this primarily means one thing: confidence in the reproducibility of the material across batches.
Dimensions that enable design freedom
Another key aspect in shipbuilding is the availability of suitable dimensions. Hull sections must be assembled across multiple structural units, reinforcement plates often need to be re-dimensioned after welding trials, and adjustments in weight distribution sometimes require wider or thicker panels. A material portfolio must be able to reflect this dynamic. AMAG’s marine programme covers thicknesses from 3 to 152.4 mm, widths up to 2,020 mm, and lengths up to 10,000 mm.
| Alloy | Temper | Thickness [mm] | Width [mm] | Length [mm] |
|---|---|---|---|---|
| 5083 | H111 | ≥ 2.000 to ≤ 2.020 | ≥ 2.000 to ≤ 2.020 | 1.000 to 10.000 |
| 5083 | H111 | ≥ 2.000 to ≤ 2.020 | ≥ 2.000 to ≤ 2.020 | 2.000 to 6.500 |
| 5083 | H116/H321 | ≥ 1.220 to ≤ 1.300 | ≥ 1.220 to ≤ 1.300 | 1.000 to 10.000 |
| 5083 | H116/H321 | ≥ 1.400 to ≤ 1.680 | ≥ 1.400 to ≤ 1.680 | 1.000 to 10.000 |
| 5083 | H116/H321 | ≥ 1.900 to ≤ 2.020 | ≥ 1.900 to ≤ 2.020 | 1.000 to 10.000 |
| 5083 | H116/H321 | ≥ 1.000 to ≤ 1.550 | ≥ 1.000 to ≤ 1.550 | 1.000 to 6.500 / 7350 (1) |
| 5083 | H116/H321 | ≥ 1.575 to ≤ 2.020 | ≥ 1.575 to ≤ 2.020 | 2.000 to 6.500 |
| 5086 | H116 | ≥ 1.000 to ≤ 1.550 | ≥ 1.000 to ≤ 1.550 | 1.000 to 6.500 / 7350 (1) |
Certifications as an integral part of the material
International shipbuilding projects are now the norm. Just as diverse are the requirements for testing, documentation, and approvals by classification societies. Material deliveries must be not only technically suitable but also formally eligible for approval. In the marine sector, AMAG is certified by DNV, Bureau Veritas, ABS, and Lloyd’s Register.Most recently, certification by RINA was added in December 2025. Particularly relevant in practice is the ability to supply products with combined approvals from several classification societies. For internationally oriented projects, this reduces interfaces, simplifies documentation, and increases planning reliability.
Sustainability
Tenders and project decisions increasingly require verifiable information on the CO₂ footprint of the materials used AMAG responds to these requirements with AMAG AL4® ever, a product line that guarantees a defined CO₂ footprint without compromising material properties. The concept is based on predefined CO₂ levels, which are verified by a mill certificate for each product and quantity. Depending on material temper, marine products can achieve CO₂ footprints below 3 t CO₂ per tonne of aluminium.This system enables a fact based discussion on sustainability, tailored to the actual technical requirements of each material and avoiding blanket statements. The ability to represent sustainability precisely and transparently fits seamlessly into AMAG’s overall philosophy for the marine sector: technically sound, reproducible, and tailored to real project requirements.Against this backdrop, the overall picture becomes clear. With a focus on proven alloys, robust processes, and international approval capability, AMAG positions itself as a reliable partner for the marine industry and for all stakeholders who need to safely integrate these materials into complex projects.
