H112
As extruded. The usual condition for machined nuts, bosses and fittings. Minimum yield 110 MPa (5083) or 190 MPa (5383).
Marine hexagon bar
5083 and 5383 Marine Grade Aluminium Hexagon Bar
5083 hexagon bar is the standard stock for aluminium nuts, bosses, couplings and fittings on welded aluminium vessels: it is the same alloy as most hull plate, resists seawater uncoated and keeps its strength when welded. 5383 is the higher-strength development of 5083 for weight-critical craft. Metline supplies both in O, H111 and H112, cut to length and certified, worldwide.
- Alloys
- 5083, 5383
- Tempers
- O, H111, H112
- Min yield, H112
- 110 MPa / 190 MPa
- Rules
- IACS UR W25 · ASTM B221
5083 and 5383 hex bar for marine fittings
5083 is the most widely used aluminium alloy in shipbuilding. Hexagon bar in the same alloy lets yards machine nuts, bosses and threaded fittings that weld straight into 5083 plating with the same filler and procedures, and that age in seawater at the same rate as the hull around them.
The alloy contains 4.0 – 4.9 % magnesium with manganese and chromium. It is not heat-treatable; extruded hex bar is supplied as-extruded (H112), annealed (O) or annealed and lightly strain-hardened (H111). Because its strength comes from solid solution rather than precipitation, welding softens it only modestly, unlike 6061 or 6082.
5383 is a tighter-controlled, slightly richer version of 5083 with more manganese and a zirconium allowance. In the extruded H112 condition its minimum yield is 190 MPa against 110 MPa for 5083, and it keeps more strength after welding. It is used where designers of fast craft want smaller, lighter fittings and is usually extruded to order.
Chemical composition of 5083 and 5383
| Element (wt %) | 5083 | 5383 |
|---|---|---|
| Silicon (Si) | 0.40 | 0.25 |
| Iron (Fe) | 0.40 | 0.25 |
| Copper (Cu) | 0.10 | 0.20 |
| Manganese (Mn) | 0.40 – 1.0 | 0.7 – 1.0 |
| Magnesium (Mg) | 4.0 – 4.9 | 4.0 – 5.2 |
| Chromium (Cr) | 0.05 – 0.25 | 0.25 |
| Zinc (Zn) | 0.25 | 0.40 |
| Titanium (Ti) | 0.15 | 0.15 |
| Zirconium (Zr) | — | 0.20 |
| Others, each / total | 0.05 / 0.15 | 0.05 / 0.15 |
| Aluminium (Al) | Remainder | Remainder |
Single figures are maximums. For 5383, zirconium (max 0.20 %) is excluded from the "others" total. Limits as in IACS UR W25 Table 1.
Mechanical properties of extruded 5083 and 5383
These are the IACS UR W25 minimums for extruded products 3 – 50 mm; ASTM B221 and EN 755-2 give the same values for 5083. Hex bar is measured across flats.
| Alloy | Temper | Yield Rp0.2 min (MPa) | Tensile Rm (MPa) | Elongation A50 / A5 min (%) |
|---|---|---|---|---|
| 5083 | O | 110 | 270 – 350 | 14 / 12 |
| 5083 | H111 | 165 | 275 | 12 / 10 |
| 5083 | H112 | 110 | 270 | 12 / 10 |
| 5383 | O / H111 | 145 | 290 | 17 / 17 |
| 5383 | H112 | 190 | 310 | — / 13 |
Source: IACS UR W25 Rev.4 Table 3. Elongation A50 up to 12.5 mm, A5 above. Actual values are reported on the mill certificate.
Physical properties of 5083
- Density
- 2.66 g/cm³ (0.096 lb/in³)
- Modulus of elasticity
- about 71 GPa
- Thermal conductivity
- about 117 – 121 W/m·K
- Electrical conductivity
- about 29 % IACS
- Coefficient of thermal expansion
- about 24 µm/m·°C (20 – 100 °C)
- Melting range
- about 574 – 638 °C
Which temper to order
H111
Annealed then lightly strain-hardened by straightening. 5083-H111 has a higher specified yield (165 MPa) than H112 because of that controlled cold work.
O
Fully annealed, for parts that will be swaged, flared or cold formed after machining.
Standards and equivalents
| Standard | Scope |
|---|---|
| IACS UR W25 and class rules | Extruded 5083 and 5383 for hull and marine structure |
| ASTM B221 / B221M | Extruded bar, rod and profiles (5083 O, H111, H112) |
| ASTM B928 / B928M | High-magnesium marine products with corrosion testing |
| EN 755-2 / EN 755-6 | Extruded bar properties / hexagonal bar dimensions and tolerances |
| EN 573-3 | Chemical composition |
| System | 5083 | 5383 |
|---|---|---|
| Aluminum Association / ASTM | 5083 | 5383 |
| UNS | A95083 | A95383 |
| European (EN 573-3) | EN AW-5083 / AlMg4.5Mn0.7 | EN AW-5383 / AlMg4.5Mn0.9 |
| German Werkstoff | 3.3547 | — |
| ISO | AlMg4.5Mn0.7 | — |
| Japan (JIS) | A5083 | — |
| China (GB/T 3190) | 5083 | 5383 |
Hex bar sizes and weights
Supply range
- Across flats
- 5083 in common metric and imperial sizes; large sections and 5383 extruded to order
- Length
- 3 m and 6 m standard, or cut lengths
- Tolerances
- EN 755-6 or ANSI H35.2 for extruded hexagonal bar
- Documents
- EN 10204 3.1; class certificate where the producing mill is approved
Hex bar weight per metre = 0.866 × s² × 2.66 / 1000 = 0.002304 × s² kg, with s the across-flats dimension in mm.
| Size (mm) | kg per metre | 3 m bar (kg) | 6 m bar (kg) |
|---|---|---|---|
| 10 | 0.230 | 0.69 | 1.4 |
| 13 | 0.389 | 1.17 | 2.3 |
| 17 | 0.666 | 2.00 | 4.0 |
| 19 | 0.832 | 2.49 | 5.0 |
| 22 | 1.11 | 3.34 | 6.7 |
| 24 | 1.33 | 3.98 | 8.0 |
| 27 | 1.68 | 5.04 | 10.1 |
| 30 | 2.07 | 6.22 | 12.4 |
| 32 | 2.36 | 7.08 | 14.2 |
| 36 | 2.99 | 8.96 | 17.9 |
| 41 | 3.87 | 11.62 | 23.2 |
| 46 | 4.87 | 14.62 | 29.2 |
| 50 | 5.76 | 17.28 | 34.6 |
| 55 | 6.97 | 20.91 | 41.8 |
| 60 | 8.29 | 24.88 | 49.8 |
| 65 | 9.73 | 29.20 | 58.4 |
| 70 | 11.29 | 33.86 | 67.7 |
| 80 | 14.74 | 44.23 | 88.5 |
| 100 | 23.04 | 69.11 | 138.2 |
Machining and welding 5083 hex bar
Machining
5083 is gummy in O and fair in H112. Use sharp, polished carbide inserts with high positive rake, high speeds and flood coolant; chip breakers help on automatic lathes.
Threads
Rolled threads outperform cut threads in fatigue. Use anti-seize or thread inserts where stainless fasteners are used.
Welding
ER5183 is the standard filler for 5083 and 5383. ER5356 is acceptable for less-stressed joints. Do not use 4xxx fillers.
Temperature limit
Avoid sustained service above about 65 °C; long exposure between about 65 °C and 200 °C can sensitise the alloy to intergranular corrosion.
Galvanic isolation
Separate from bronze, copper and stainless steel with insulating sleeves and washers.
Finishing
Normally left bare in seawater service; can be anodised or painted.
Typical applications
- Nuts, couplings and unions for seawater cooling, bilge and drain lines
- Through-hull and deck bosses welded into 5083 plating
- Standoffs and mounting studs for equipment and consoles
- Cleats, fairleads and bollard parts on workboats and ferries
- High-strength fittings in 5383 on fast ferries and patrol craft
- Offshore, aquaculture and port hardware in permanent immersion
5083 hex bar compared with other options
| Property | 5052-H112 | 5083-H112 | 5383-H112 | 6082-T6 |
|---|---|---|---|---|
| Min yield (extruded) | 70 MPa | 110 MPa | 190 MPa | 260 MPa |
| Min tensile | 170 MPa | 270 MPa | 310 MPa | 310 MPa |
| Seawater immersion | Very good | Excellent | Excellent | Needs protection |
| Class-listed extrusion | No | Yes | Yes | Yes, protected |
How to order
- SpecifyAlloy (5083 or 5383), temper, across-flats size, length, quantity, standard and class requirement.
- QuoteAvailability, certificates and EXW, FOB, CIF or DAP terms confirmed.
- InspectDimensions, straightness and surface checked; bars cut to length if required.
- ShipBundled in wooden cases with EN 10204 3.1 or class certificates.
References and standards
- IACS Unified Requirement W25 – Aluminium alloys for hull construction and marine structure
- ASTM B221 – Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles and Tubes
- EN 755-2 – Extruded rod/bar, tube and profiles: mechanical properties (with EN 755-3, -4 and -6 for round, square and hexagonal bar tolerances)
- ASTM B928/B928M – High Magnesium Aluminum-Alloy Products for Marine Service and Similar Environments
- The Aluminum Association – International Alloy Designations and Chemical Composition Limits (Teal Sheets)
5083 and 5383 aluminium (aluminum) hex bar: FAQ
What is the yield strength of 5083-H112 hex bar?
The specified minimum is 110 MPa, with minimum tensile strength 270 MPa, under ASTM B221, EN 755-2 and IACS UR W25. Actual values are usually higher.
What is the difference between 5083 and 5383?
5383 is a more tightly controlled variant with more manganese and a zirconium allowance. Extruded 5383-H112 has a minimum yield of 190 MPa against 110 MPa for 5083 and keeps more strength after welding.
Can 5083 hex bar be welded to 5083 plate?
Yes, with ER5183 filler and the same procedure used for the hull. That is one of the main reasons for using 5083 hex for marine fittings.
How much does 5083 hex bar weigh?
About 0.002304 × (across flats in mm)² kg per metre. A 30 mm hex weighs about 2.07 kg/m.
Is 5083 hex bar suitable for hot areas?
Not for sustained service above about 65 °C, where sensitisation can occur. Use 5454 for warm areas.
Need 5083 hex bar?
Send size, temper, length and quantity. Metline will reply with availability, certificates and a delivered price.
