5083 Aluminum Sheet and Plate

What Is 5083 Aluminum?

5083 is a high-magnesium Al-Mg (non-heat-treatable) alloy containing 4.0–4.9% Mg and 0.4–1.0% Mn. The elevated magnesium content produces a dense, self-healing oxide film that gives 5083 the best seawater corrosion resistance of any common structural aluminum alloy.

In short: 5083 is the industry-standard alloy for structural hull plating, offshore platforms, and cryogenic pressure vessels wherever strength, weldability, and seawater resistance must coexist.

Product Specifications

Temper Selection Guide

Quick Comparison

Detailed Temper Profiles

5083-H116 — The Marine Standard

• Why it matters: H116 is the only temper mandated by ASTM B928 for marine hull plate exposed to seawater. Its controlled thermomechanical processing ensures resistance to both exfoliation corrosion (ASTM G66 ≤ PB) and intergranular corrosion (ASTM G67 NAMLT ≤15 mg/cm²).
• Certifications: DNV·GL, ABS, LR, CCS full classification society approval.
• Applications: Ship keels, hull shells, polar icebreaker plating, offshore platform decks.

5083-H321 — Heavy Plate & High Impact

• Edge: Available in thicknesses up to 250 mm; stabilized at higher temperatures for thick-section performance.
• Applications: Coal/ore carrier floors, military armor plate, manned submersible pressure hulls.

5083-H112 — Cost-Effective Structural

• Edge: ~15% lower processing cost than H116 while delivering UTS ≥275 MPa and Yield ≥125 MPa.
• Applications: Oil/chemical tanker shells, industrial piping, non-classified marine structures.

5083-O — Formability & Cryogenics

• Edge: Elongation ≥14%; excellent cold formability for dished heads and deep-drawn shapes.
• Applications: LNG tank components (−162°C service), cryogenic pressure vessels, spun/formed parts.

Chemical Composition (per ASTM B209 / B928)

Critical note: Mg content above 3% makes the alloy susceptible to sensitization (β-phase Al₃Mg₂precipitation at grain boundaries). The H116 and H321 tempers incorporate thermal stabilization (200–250°C) to distribute precipitates uniformly and prevent this failure mode. Verify with ASTM G67 on every production lot.

Physical Properties

Mechanical Properties

Additional data:

• Fatigue strength: ~160 MPa at 5 × 10⁸cycles (R =−1).
• Shear strength: ~175 MPa (H116).
• Weld-zone strength: ≥275 MPa tensile with ER5183 filler (≥90% of O-temper parent).

Processing & Fabrication

Forming

Welding

Surface prep: Remove oxide layer with stainless-steel brush or chemical etch before welding. Never use carbon-steel wire wheels — iron contamination creates corrosion initiation sites.

Cutting & Machining

• Sawing/shearing: Standard for plate ≤25 mm; plasma or waterjet for thicker sections.
• CNC machining: Carbide tooling, high spindle speed (2000–4000 RPM), flood coolant.
• Note: 5083 work-hardens during machining — use sharp tools and avoid dwelling.

5083 vs. Other Marine Alloys

When to upgrade from 5052 → 5083: Any structural marine component exposed to direct seawater, requiring class society certification, or serving at cryogenic temperatures.

Stock Inventory

We stock 5083 plate in O, H116, and H321 tempers across a full range of thicknesses. All cut-to-size. Contact us for current availability.

5083-O Aluminum Sheet and Plate in Stock

Standards: ASTM B209, ASME SB209. All supplied with mill test reports.

5083-H116 Aluminum Sheet and Plate in Stock

All sizes cut to order. Width and length per customer specification.

5083-H321 Aluminum Sheet and Plate in Stock

Packaging & Shipping

Pricing

FOB Price = SMM A00 Aluminum Ingot Price + Processing Fee

FAQ

What is the difference between 5083-H116 and 5083-H321?

Both deliver ≥303 MPa tensile and ≥215 MPa yield. The key difference is corrosion qualification: H116 is specifically tested to ASTM B928 for exfoliation and intergranular corrosion resistance and is mandatory for classified marine hull plate. H321 is thermally stabilized at a higher temperature and is more common in thick plate for armor and heavy structural applications. For shipbuilding, always specify H116.

Can 5083 be used for LNG tanks?

Yes — 5083-O is the primary alloy for LNG containment systems (−162°C). It retains excellent ductility and fracture toughness at cryogenic temperatures, certified per EN 13445 and ASME Section VIII.

What filler wire should I use to weld 5083?

ER5183 (Al-4.5Mg-0.7Mn) is preferred for maximum joint strength (~275 MPa). ER5356 (Al-5Mg) is also acceptable and more widely available. Always use 100% argon shielding and clean joints within 4 hours of welding.

Is 5083 better than 5052 for marine use?

For structural components exposed to seawater — yes. 5083 offers ~30% higher strength and superior exfoliation corrosion resistance (H116 temper). However, 5052 is more formable, ~30% cheaper, and perfectly adequate for non-structural marine parts like fuel tanks, interiors, and ductwork.

What class society certifications does your 5083 carry?

Our 5083-H116 and H321 plates are certified by DNV·GL, ABS, Lloyd's Register (LR), CCS, BV, NK, and KR. All plates ship with original mill test reports plus third-party verification on request.

Does 5083 require surface coating in seawater?

Bare 5083-H116 resists seawater corrosion without coating. However, for below-waterline hull surfaces, most classification rules require an epoxy anti-fouling coating system plus cathodic protection (Zn-Al anodes) as supplementary protection to maximize service life.