Aluminum 5083 · temper
Aluminum 5083-H321
Properties of the H321 condition, compared with the other 5083 tempers.
Mechanically equivalent to H116 but produced by a stabilizing thermal treatment; specified by many shipyards and pressure-vessel codes (ASME).
What is 5083-H321?
5083-H321 is 5083 in the H321 temper — mechanically equivalent to H116 but produced by a stabilizing thermal treatment; specified by many shipyards and pressure-vessel codes (ASME). 5083-H321 has a yield strength of 228 MPa (33.1 ksi) and a tensile strength of 317 MPa (46 ksi) — stronger than 59% of aluminum grades. Elongation at break is 16% and the elastic modulus is 71 GPa (10.3 Msi). 5083-H321 has a density of 2.66 g/cm³ (0.0961 lb/in³), lighter than 84% of aluminum grades. It melts at 574°C (1,065 °F).
Advantages
- Good corrosion resistance — 82/100, better than 99% of aluminum grades
- Tough — resists crack growth — 34 MPa·√m (30.9 ksi·√in), better than 90% of aluminum grades
- Readily welded — 90/100, better than 90% of aluminum grades
- Ductile — tolerates forming and impact — 16%, better than 84% of aluminum grades
Limitations
- Limited service temperature — 65°C (149 °F), worse than 97% of aluminum grades
- Poor heat conductor — 117 W/m·K (67.6 BTU/hr·ft·°F), worse than 83% of aluminum grades
- Low electrical conductivity — 29 % IACS, worse than 78% of aluminum grades
5083-H321 properties
Typical room-temperature values for 5083-H321 — 12 properties are specific to this condition; the rest are grade-level values shared by every 5083 temper. Each bar shows where the value sits among the aluminum grades in FabDigit's library — further right is higher.
Physical3
5083-H321 has a density of 2.66 g/cm³ (0.0961 lb/in³), lighter than 84% of aluminum grades. It melts at 574°C (1,065 °F).
Mechanical12
5083-H321 has a yield strength of 228 MPa (33.1 ksi) and a tensile strength of 317 MPa (46 ksi) — stronger than 59% of aluminum grades. Elongation at break is 16% and the elastic modulus is 71 GPa (10.3 Msi).
Thermal6
5083-H321 is rated for continuous service to 65°C (149 °F). It conducts heat at 117 W/m·K (67.6 BTU/hr·ft·°F), worse than 83% of aluminum grades. Thermal expansion is 23.8 µm/m·K (13.2 µin/in·°F).
Electrical3
5083-H321 conducts electricity at 29 % IACS, worse than 78% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is very good (82/100), better than 99% of aluminum grades.
Sustainability4
Producing a kilogram of 5083-H321 takes about 175 MJ of energy and emits 11.5 kg of CO₂ — less than 92% of aluminum grades. Typical recycled content is 30%.
Manufacturability8
5083-H321's machinability is fair (50/100, worse than 65% of aluminum grades); weldability excellent (90/100); formability good (55/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 5083 tempers and conditions
5083 is also supplied in 16 other conditions. The full side-by-side table is on the 5083 overview.
- H36Three-quarter-hard stabilized 5083 sheet: highest practical cold-worked strength while keeping the corrosion stability of the H3x series.305 MPa yield · 96 HB
- H343Highest-strength standard 5083 sheet temper; used for hard-worked tank and body panels where bend radii can stay generous.300 MPa yield · 100 HB
- H16Three-quarter-hard cold-rolled 5083 with high strength and limited bend ductility; unstabilized high-Mg temper reserved for cold, dry-service applications.290 MPa yield · 95 HB
- H26Three-quarter-hard back-annealed sheet: near-maximum cold-worked strength for 5083 with slightly better ductility and stability than H16.285 MPa yield · 93 HB
- H34Half-hard sheet given a low-temperature stabilizing treatment; high yield strength with the sensitization resistance needed for high-Mg 5083.275 MPa yield · 90 HB
- H14Half-hard cold-rolled 5083 sheet: substantially higher yield strength with reduced ductility; unstabilized so not recommended for hot or long-term marine service.255 MPa yield · 90 HB
- H24Half-hard sheet produced by over-rolling and back-annealing; good balance of strength and bendability for formed marine and vehicle panels.250 MPa yield · 88 HB
- H323Sheet temper for formed parts needing higher strength than H321 with SCC-resistant processing (tanks, trailer panels).250 MPa yield · 90 HB
- H116Default marine/LNG plate temper: qualified to ASTM B928 exfoliation (ASTM G66) and intergranular (G67) tests for continuous saltwater immersion.228 MPa yield · 85 HB
- H321Mechanically equivalent to H116 but produced by a stabilizing thermal treatment; specified by many shipyards and pressure-vessel codes (ASME).228 MPa yield · 85 HB
- H12Strain hardened only to quarter-hard; higher yield than O but unstabilized, so long-term exposure above ~65 °C risks sensitization and stress-corrosion cracking.200 MPa yield · 85 HB
- H22Over-worked then back-annealed to quarter-hard; quarter-hard strength with better ductility and more stable structure than H12.195 MPa yield · 82 HB
- H111Standard temper for 5083 extrusions and lightly worked sheet where near-annealed ductility is wanted with a small strength bonus.165 MPa yield · 70 HB
- OPick for maximum formability — deep drawing, tight bends, spinning — or where post-form welding will anneal the part anyway.145 MPa yield · 65 HB
- FAs-fabricated hot-worked 5083 with no guaranteed mechanical limits; properties near annealed level and dependent on the forming route.145 MPa yield · 72 HB
Working with 5083-H321
Is 5083 easy to machine?
Cuts easily but gummy — use sharp polished high-rake carbide, high surface speed, generous flood coolant or lubricant to avoid built-up edge; harder H32x/H34x tempers give cleaner chips than O.
Can 5083 be welded?
Excellent for GMAW/GTAW and friction stir with 5183 (highest strength) or 5356 filler; never use 4043 or 4xxx fillers (brittle Mg₂Si), keep interpass temperature low and avoid prolonged heating above 65 °C.
Can 5083 be formed, bent or molded?
Form in O or H111 for tight radii; H116/H321 plate bends well at generous radii but shows springback and Lüders/orange-peel markings — hot forming 200–250 °C is possible but re-sensitizes the alloy.
What surface finishes work on 5083?
Takes clear and hard anodizing well and paints/powder-coats readily after chromate-free conversion coating; leave mill or brushed finish for marine work, and do not plate or braze.
5083 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Si | ≤ 0.4 | 0.15 |
| Fe | ≤ 0.4 | 0.25 |
| Cu | ≤ 0.1 | 0.03 |
| Mngrain-structure control | 0.4 – 1 | 0.7 |
| Mgprimary strengthening element | 4 – 4.9 | 4.45 |
| Cr | 0.05 – 0.25 | 0.12 |
| Zn | ≤ 0.25 | 0.05 |
| Ti | ≤ 0.15 | 0.03 |
| Others (each)0.15 % total | ≤ 0.05 | — |
| Alremainder, nominally ~94 % | balance | — |
5083-H321 — frequently asked
What is 5083-H321 used for?
5083-H321 is typically used for ship hulls and superstructures, LNG and cryogenic storage tanks, welded pressure vessels, tank trailers and road tankers, armour-grade plate and marine deck fittings and hardware. In short: tough marine alloy; impact resistant.
What is the yield strength of 5083-H321?
5083-H321 has a typical yield strength of 228 MPa (33.1 ksi) and a tensile strength of 317 MPa (46 ksi) — stronger than 59% of aluminum grades. Strength varies by condition: see the 17 listed tempers.
Is 5083-H321 easy to machine?
Reasonably — machinability is rated fair (50/100, worse than 65% of aluminum grades). Cuts easily but gummy — use sharp polished high-rake carbide, high surface speed, generous flood coolant or lubricant to avoid built-up edge; harder H32x/H34x tempers give cleaner chips than O.
Can 5083-H321 be welded?
Yes — weldability is rated excellent (90/100). Excellent for GMAW/GTAW and friction stir with 5183 (highest strength) or 5356 filler; never use 4043 or 4xxx fillers (brittle Mg₂Si), keep interpass temperature low and avoid prolonged heating above 65 °C.
What surface finishes work on 5083-H321?
Takes clear and hard anodizing well and paints/powder-coats readily after chromate-free conversion coating; leave mill or brushed finish for marine work, and do not plate or braze.
Can 5083-H321 be formed, bent or molded?
Form in O or H111 for tight radii; H116/H321 plate bends well at generous radii but shows springback and Lüders/orange-peel markings — hot forming 200–250 °C is possible but re-sensitizes the alloy.
What is the maximum service temperature of 5083-H321?
5083-H321 is rated for continuous use to about 65°C (149 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in 5083-H321?
Yes — 5083-H321 is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM B209 — Aluminum and Aluminum-Alloy Sheet and Plate — ASTM International (2021)
- ASTM B928 — High Magnesium Aluminum-Alloy Sheet and Plate for Marine Service — ASTM International (2019)
- EN 485-2 / EN 573-3 (EN AW-5083, AlMg4.5Mn0.7) — CEN (2018)
- International Alloy Designations and Chemical Composition Limits (Teal Sheets) — The Aluminum Association (2018)
- ASM Handbook Vol. 2 — Properties of Nonferrous Alloys — ASM International (1990)
- MMPDS-16 (Metallic Materials Properties Development and Standardization) — Battelle/FAA (2021)
- Marine plate 5083 H116/H321 datasheets — Constellium / Alcoa (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.