5251 is a medium-strength aluminum-magnesium alloy (AlMg2) with very good corrosion resistance, especially in marine environments, and good weldability. It is supplied in sheet, plate, bar, tube, and wire across O, H22, H24, H32, H34, and H38 tempers for boats, panels, and transport use.
Available forms: sheet / plate / bar / tube / wire / coil
Common tempers: O, H22, H24, H32, H34, H38
Processing support: CNC machining / laser cutting / welding / anodizing
Quality documents: MTC report with every order
5251 Aluminum Alloy (AlMg2) is a non-heat-treatable aluminum-magnesium (5xxx) alloy. Its strength comes from magnesium in solid solution and strain hardening, not heat treatment. It offers good corrosion resistance—especially in marine and industrial environments—and welds well, which makes it a common choice for structures exposed to water, chemicals, or cycling loads.
5251 Aluminum Alloy is supplied in several forms and tempers. Standard size ranges are below; other dimensions can be discussed with our team.
| Item | Range |
|---|---|
| Thickness | 0.5 – 150 mm |
| Width | 1000 – 3000 mm |
| Length | 1000 – 6000 mm |
| Common tempers | O, H22, H24, H32, H34, H38 |
| Item | Range |
|---|---|
| Diameter / side | 6 – 400 mm |
| Length | 1000 – 6000 mm |
| Common tempers | O, H22, H24, H32, H34, H38 |
| Item | Range |
|---|---|
| Outer diameter | 6 – 400 mm |
| Wall thickness | 0.5 – 40 mm |
| Length | 1000 – 6000 mm |
| Common tempers | O, H22, H24, H32, H34, H38 |
| Item | Range |
|---|---|
| Diameter | 0.8 – 12 mm |
| Coil weight | 10 – 500 kg |
| Size tolerance | ± 0.05 mm |
| Common tempers | O, H22, H24, H32, H34, H38 |
| Standard | Designation |
|---|---|
| AA (USA) | 5251 Aluminum Alloy |
| EN AW | AlMg2 |
| Series | 5000 (Al-Mg, non-heat-treatable) |
| Element | Weight % |
|---|---|
| Si | 0.40 max |
| Fe | 0.50 max |
| Cu | 0.15 max |
| Mn | 0.10 – 0.50 |
| Mg | 1.7 – 2.4 |
| Cr | 0.30 max |
| Zn | 0.20 max |
| Ti | 0.20 max |
| Al | Balance |
Values are typical AA composition ranges; confirm against the ordered specification and the supplied MTC.
| Temper | Tensile (MPa) | Yield (MPa) | Elongation (%) | Brinell |
|---|---|---|---|---|
| O | 210 | 90 | 18 | 55 |
| H22 / H32 | 230 | 130 | 14 | 60 |
| H24 / H34 | 250 | 160 | 10 | 65 |
| H38 | 270 | 200 | 7 | 70 |
Mechanical values are representative room-temperature typicals for plate, sheet, or bar and should be confirmed against the ordered thickness and the supplied MTC.
Choose the softest temper that meets the strength need to keep forming and welding straightforward.
A medium-strength 5xxx alloy with good all-round properties for general fabrication.
Very good in marine and outdoor environments; suitable for boat and transport use.
Welds well and forms readily in softer tempers.
5251 Aluminum Alloy is a non-heat-treatable 5xxx alloy, so strength comes from strain hardening (H-tempers), not heat treatment. It cuts, drills, and welds well with standard aluminum tooling.
Note: anodized color of 5xxx alloys can differ slightly from 6xxx alloys; confirm the finish on a sample if color match matters.
Every 5086 order ships with a Mill Test Certificate (MTC) that reports the actual chemical analysis and mechanical results for the supplied material. Third-party SGS or equivalent test reports can be arranged on request for project or tender requirements.
Linsy Aluminum is a Shenzhen-based aluminum supplier with more than 20 years of experience serving marine, transport, and general engineering customers. We supply 1000–8000 series material in plate, bar, tube, wire, coil, profile, and block forms.
For a quote, share your alloy, temper, dimensions, quantity, and any certificate requirements.
No. 5251 is a non-heat-treatable 5xxx alloy; strength comes from magnesium and strain hardening.
O, H22, H24, H32, H34, and H38 are typical for sheet, bar, and tube.
Both are medium-strength 5xxx alloys with similar corrosion behavior. Choice often comes down to available temper, thickness, and local specification.
Custom sizes are usually produced within 10–60 days depending on alloy, temper, and quantity. Confirm the schedule when you request a quote.
Yes. An MTC is provided with every order, and third-party test reports can be arranged on request.
Mill finish, anodizing, polishing, powder coating, and PVC film are available depending on the form.
We support low MOQs for custom requests. Share your required size and quantity for a quote.
Linsy Advantages
Linsy Aluminum is a leading supplier of aluminum processing products, serving diverse industries including aerospace, general engineering, automotive, marine, shipbuilding and other specialized industrial applications.
We are committed to maintaining the highest standards of quality and environmental responsibility, as demonstrated by our certifications: ISO 9001:2008， ISO 14001:2004 and SGS.
