Aluminum Plate for Ship Deck: Grades, Tempers, Dimensions & Buyer’s Guide
Last updated: August 2026 — Reviewed by Delin Aluminum Marine Engineering Team
Choosing the wrong aluminum plate for a ship deck can lead to corrosion, slipping accidents, and costly rework within a single season at sea. If you are specifying material for a yacht, ferry, or commercial vessel, this guide will walk you through the alloys, tempers, thicknesses, and patterns that professional shipbuilders trust. We will also show you how to read the most common specification table so you can order with confidence.
By the end of this page, you will know exactly which marine-grade aluminum plate matches your hull design — and where to source it at mill-direct prices.
- What Is a Ship Deck and Why It Matters
- Key Functions of a Marine Aluminum Deck
- Main Aluminum Alloys Used for Ship Decks
- 5052 Aluminum Check Plate
- 5083 Aluminum Deck Plate
- 5086 Aluminum Diamond Plate
- 6061 Aluminum Tread Plate
- Specification of Aluminum Deck Plate
- Common Pattern Types
- Ship Types That Use Aluminum Decks
- Certifications & Quality Standards
- People Also Ask
- Related Product
- Request a Free Quote
1. What Is a Ship Deck and Why Does Material Choice Matter?
A ship deck is the horizontal plate surface that separates the hull into upper and lower compartments. Together with the deck framework, it carries crew, cargo, vehicles, and weather loads 24 hours a day, 365 days a year.
On a typical vessel, the deck absorbs:
- Foot traffic and rolling cargo
- Sea-spray, rain, and UV exposure
- Oil, fuel, and chemical contamination
- Thermal cycling between tropical sun and cold ocean air
Because of this constant abuse, the deck plate is one of the most demanding structural components on any vessel. Steel is heavy and corrodes; wood rots; fiberglass cracks. Marine-grade aluminum plate — especially the 5xxx series — offers the best combination of light weight, corrosion resistance, weldability, and slip resistance.
2. Key Functions of a Marine Aluminum Deck
The aluminum deck plate on a ship serves four critical functions:
- Structural support — distributes vertical and lateral loads from cargo and waves into the hull.
- Watertight boundary — partitions the hull into independent watertight compartments, improving survivability.
- Working platform — provides a safe surface for crew to walk, work, and operate equipment.
- Anti-slip surface — the raised pattern of a tread plate dramatically reduces slip accidents in wet conditions.
To meet all four functions, the deck plate must be corrosion-resistant, slip-resistant, wear-resistant, and easy to clean. This is exactly why 5052, 5083, 5086, and 6061 aluminum checkered plates dominate shipyard order books worldwide.
3. Main Aluminum Alloys Used for Ship Decks
The four alloys below account for over 95% of marine aluminum deck plate orders. They are all from the 5xxx or 6xxx series — known for high strength, weldability, and seawater resistance.
| Alloy Series | Representative Grade | Key Strength | Common Temper | Typical Use on Deck |
|---|---|---|---|---|
| 5xxx (Al-Mg) | 5052 | Excellent corrosion resistance, easy forming | H32, H34, H114 | Small craft, superstructure decking |
| 5xxx (Al-Mg) | 5083 | Highest strength in 5xxx series | H116, H321, H112 | Yachts, ferries, work boats, hull & deck |
| 5xxx (Al-Mg) | 5086 | Strong weldability, marine-grade | H116, H321, H112 | Large commercial vessels, LNG carriers |
| 6xxx (Al-Mg-Si) | 6061 | Heat-treatable, structural | T6, T651 | Structural framing, walkways, consoles |
4. 5052 Aluminum Check Plate
5052 aluminum check plate is the lightweight entry point for marine decks. With about 2.5% magnesium, it has a tensile strength around 200 N/mm² and elongation over 10%, so it bends without cracking under foot traffic and minor impacts.
It weighs only about 7 kg per square meter at typical thickness. That low mass reduces the vessel’s overall weight and improves fuel economy — a big advantage for small fishing boats and inland ferries.
Best for: small recreational boats, dinghies, pontoon decks, and non-structural inner decks where weight saving matters more than ultimate strength.
5. 5083 Aluminum Deck Plate
5083 aluminum deck plate is the workhorse of the marine industry. With 4.0–4.9% magnesium, it is the strongest non-heat-treatable alloy in common marine use. It has been successfully applied on yachts, ferries, cruise ships, and work boats for decades.
The most common tempers are:
- 5083-H116 — for hull bottoms and decks exposed to seawater.
- 5083-H112 — general structural use.
- 5083-H321 — the preferred temper for marine certification (DNV).
5083 resists corrosion in natural seawater, galvanic couples, and salt spray, and its weldability is excellent — it does not crack during standard MIG or TIG welding.
For ship decks specifically, Delin recommends 5083-H116 tread plate in 4 mm, 5 mm, or 6 mm thickness.
6. 5086 Aluminum Diamond Plate
5086 aluminum diamond plate is often specified for larger vessels such as LNG carriers and offshore support vessels. Its magnesium content (3.5–4.5%) gives slightly lower strength than 5083, but its corrosion resistance in long-term immersion is on par.
Weldability is one of 5086’s strongest selling points — it welds cleanly with no hot-cracking tendency. That makes it ideal for large deck panels that must be welded into the hull without post-weld stress relief.
7. 6061 Aluminum Tread Plate
6061 aluminum tread plate is the only heat-treatable alloy on this list. In T6 or T651 temper, it offers the highest mechanical strength — perfect for wheelhouse floors, mast platforms, and structural walkways.
However, 6061 has lower seawater resistance than 5083/5086 and can suffer stress-corrosion cracking if used incorrectly. For this reason, 6061 is reserved for non-immersed, structural deck applications where its extra strength pays off.
8. Specification of Aluminum Deck Plate
The table below is the standard specification used by Delin Aluminum for marine-grade deck plate. It covers the four alloys discussed above with the tempers, thicknesses, and panel sizes most shipyards order.
| Alloy | Temper | Thickness (mm) | Width (mm) | Length (mm) |
|---|---|---|---|---|
| 5052 | F, O, H12, H14, H16, H18, H19, H22, H24, H26, H28, H32, H34, H36, H38, H111, H112, H114 | 3 – 50 | 20 – 2650 | 500 – 16000 |
| 5083 | O, H12, H14, H16, H18, H19, H22, H24, H26, H28, H32, H34, H36, H38, H111, H112, H114, H116, H321 | 3 – 50 | 20 – 2600 | 500 – 16000 |
| 5086 | O, H111, H112, H116, H321 | 3 – 50 | ≤ 3600 | 500 – 16000 |
| 6061 | F, O, T4, T6, T651 | 3 – 500 | 500 – 2800 | 500 – 16000 |
Reading the table: for a 6 mm 5083-H116 deck panel for a 12 m fishing vessel, you would typically order 1500 × 6000 mm plates to minimize welds. Delin can cut to any custom size from the same mill stock.
9. Common Pattern Types
Aluminum deck plate comes in several raised patterns. The choice affects both slip resistance and cleaning ease.
- One-bar (single diamond) — a classic look, common on small leisure boats.
- Two-bar — slightly more grip than one-bar, used on work boats.
- Three-bar — a good balance of slip resistance and cleanability.
- Five-bar — the most popular marine pattern. Excellent anti-slip performance, easy to sweep clean.
- Diamond / lentil — traditional pattern, less common today but still specified for some heritage and replica vessels.
10. Ship Types That Use Aluminum Decks
Across the global shipbuilding industry, aluminum deck plate appears on an enormous range of vessels. The table below summarizes the most common applications.
| Vessel Category | Examples | Typical Deck Alloy & Temper |
|---|---|---|
| Transport ships | Passenger ships, ferries, LNG carriers, container ships | 5083-H116, 5086-H116, 5052-H32 |
| Fishing boats | Trawlers, purse seiners, longliners, squid boats | 5083-H116, 5052-H32/H34 |
| High-speed craft | Hydrofoils, hovercraft, fast ferries | 5083-H116, 5086-H321 |
| Crew transfer & survey craft | CTVs, survey and dive support vessels | 5083-H116, 5086-H116, 5456-H116 |
| Yachts & pleasure craft | Motor yachts, sailing yachts | 5052-H32, 5083-H116, 6061-T6 (structure) |
| Offshore platforms | Drilling rigs, accommodation barges | 5083-H116, 5086-H321, 5454-H32 |
| Work boats | Tugboats, pilot boats, supply vessels | 5083-H116, 5086-H116 |
11. Certifications & Quality Standards
When you order marine aluminum deck plate, always ask for:
- DNV-recognised marine grades — 5083, 5086 and 5754, supplied to ASTM B209 / EN 485-2.
- Mill Test Certificate (EN 10204 3.1) — confirms chemistry and mechanical properties.
- Compliance with ASTM B209 or EN 485 — the two main product standards for marine plate.
12. People Also Ask
Which aluminum alloy is best for a ship deck?
For most ship decks — especially on commercial vessels, yachts, and work boats — 5083-H116 is the best all-around choice. It offers the highest strength among non-heat-treatable marine alloys, excellent seawater corrosion resistance, and trouble-free welding. For very light-duty decks on small boats, 5052-H32 is a more economical alternative.
What thickness of aluminum plate is used for ship decks?
Most ship decks use 4 mm to 8 mm aluminum tread plate. Small leisure boats typically use 3–4 mm; work boats and yachts use 5–6 mm; commercial vessels and workboats use 6–10 mm for heavily loaded decks. Anything thicker than 10 mm is reserved for special-purpose structures.
What is the difference between H116 and H321 temper?
Both are marine-grade tempers for 5xxx alloys with more than 3% magnesium. H116 is strain-hardened and stabilized for seawater service. H321 is a low-temperature heat-treated variant of H116 with slightly better formability. Both are accepted by classification societies; H321 is often required by DNV for certain applications.
Can aluminum deck plate be welded?
Yes. 5083, 5086, and 5052 all weld cleanly with MIG (GMAW) or TIG (GTAW) processes using 5183 or 5356 filler wire. 6061-T6 can also be welded (with 4043 or 5356 filler) but loses about 30–40% of its strength in the heat-affected zone, so welded 6061 is rarely used for primary deck plating.
How long does an aluminum ship deck last?
With proper alloy selection and basic maintenance (freshwater rinse, anti-fouling), an aluminum deck plate will last 20 to 30+ years in service. 5083-H116 decks on well-maintained yachts have been in continuous use for over 25 years without replacement.
Is aluminum deck plate slippery when wet?
Smooth aluminum plate is slippery when wet, but a properly patterned 5-bar tread plate reduces slip risk dramatically — usually meeting or exceeding international anti-slip standards for marine walkways. For maximum safety, choose a 5-bar pattern oriented across the direction of foot traffic.
13. Related Product
Below are the marine-grade aluminum plates Delin Aluminum supplies for ship deck and related hull applications. Click through for full specifications, mechanical properties, and mill certificates.
5083 Aluminum Sheet for Marine
Temper: H111, H112, H116, H321 — the most popular marine plate, DNV & CCS certified.
6061 Aluminum Sheet
Heat-treatable structural alloy. Tempers T6, T651. Best for wheelhouse floors and consoles.
14. Request a Free Quote
Need a specific alloy, temper, or panel size for your ship deck project? Send us your drawing or rough dimensions and our marine engineering team will respond within 12 hours with a mill-direct quotation.
What to include in your inquiry:
- Alloy & temper (e.g., 5083-H116, 5052-H32)
- Thickness × width × length (or panel layout)
- Pattern type (1-bar, 5-bar, diamond)
- Quantity (pieces or total tonnage)
- Delivery port & destination
- Certification required (DNV, CCS, ABS, etc.)
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References: Hou Shizhong, “Research and Application of Aluminum Alloy for Ships,” Light Alloy Fabrication Technology, 2019; Wang Jue, “Application and Development of Aluminum Alloys in Shipbuilding,” Light Metals, 1994. Internal data from Delin Aluminum marine plate supply records.
