What-is-the-difference-between-5083-H116-and-H321-aluminum-sheet.pdf
Both GNEE 5083-H116 and 5083-H321 are marine-grade aluminum alloys within the 5xxx series (Al Mg4.5Mn0.7). While they share identical base chemical compositions, their tempering processes differ, leading to distinct performance characteristics and application suitability.
Comparison Table: 5083-H116 vs. H321
| Aspect | 5083-H116 | 5083-H321 |
|---|---|---|
| Processing Method | Strain-hardened only | Strain-hardened and thermally stabilized |
| Tensile Yield Strength | ~230 MPa (33 ksi) | ~240 MPa (35 ksi) |
| Ultimate Tensile Strength | ~320 MPa (47 ksi) | ~330 MPa (48 ksi) |
| Elongation at Break | ~12 % | ~13 % |
| Brinell Hardness (HB) | 83 | 89 |
| Corrosion Resistance | Excellent seawater resistance; suitable for long-term underwater environments | Enhanced resistance to exfoliation and intergranular corrosion; ideal for highly corrosive or chemical-exposure conditions |
| Stability | Contains residual stress from cold working | Reduced residual stress; improved dimensional stability |
| Fatigue Resistance | Standard performance | Superior under dynamic loads |
| Weldability & Formability | Requires strict control in forming | Better weldability and formability; suitable for complex structures |
| Optimal Applications | Non-welded marine structures (e.g., hull panels, ship decks) | Welded components and dynamic-load structures (e.g., pressure vessels, offshore platforms) |
| Thermal Endurance | Suitable for continuous use up to 66°C | Maintains performance under thermal variation |
Key Differences Explained
Temper Definitions & Processing
GNEE 5083-H116: This temper undergoes strain hardening (cold working) without subsequent thermal treatment. It must pass stringent ASTM G66/G67 exfoliation and intergranular corrosion tests. With magnesium content ≥4%, it is optimized for marine load-bearing applications.
GNEE 5083-H321: In addition to strain hardening, this variant receives a stabilization heat treatment. This low-temperature annealing process reduces residual stresses, enhances dimensional stability, and improves resistance to stress corrosion cracking.
Mechanical Properties
The H321 temper provides approximately 5% higher strength and slightly improved ductility compared to H116, due to its stabilized microstructure.
Corrosion Performance
Both alloys demonstrate strong corrosion resistance in seawater. However, GNEE 5083-H321 offers superior performance in exfoliation and intergranular corrosion tests. Its stabilized nature also ensures lower susceptibility to stress corrosion cracking in welded areas.
Application Suitability
GNEE 5083-H116 is typically specified for standard marine applications where welding is minimal.
GNEE 5083-H321 is preferred for welded structures and components exposed to highly corrosive environments, including chemical processing and underwater applications.
Why Choose GNEE Aluminum Alloys?
GNEE's 5083-H116 and H321 aluminum plates are manufactured under precise thermal-mechanical controls. The H321 variant, with its additional stabilization step, delivers enhanced reliability for critical marine and industrial structures, ensuring long-term performance under demanding conditions.
