What Is ASTM B209 3003-H26 Aluminum Sheet?
ASTM B209 3003-H26 is a non-heat-treatable aluminum-manganese sheet produced to the ASTM B209 specification. Alloy 3003 is the most widely used general-purpose aluminum alloy: it adds roughly 1.0-1.5% manganese to pure aluminum, which raises strength above the 1xxx series while keeping excellent formability, weldability, and corrosion resistance. The H26 temper identifies a strain-hardened and partially annealed condition at about 3/4 hard, so the sheet is noticeably stronger and stiffer than the common H14 half-hard temper while remaining workable for bending and light forming. The same material is covered internationally by EN 485-2 (EN AW-3003), JIS H4000 (A3003), and GB/T 3880.
In the H2X temper family the metal is strain hardened by cold rolling and then partially annealed to restore some ductility. The digit 6 means approximately 3/4 hard: the strength sits between H24 (half hard) and H28 (full hard). The result is a sheet with higher tensile strength and dent resistance than H14, but lower elongation, so it is not suitable for deep drawing. Typical processing includes slitting to custom widths, cut-to-length, and press-brake bending with a generous bend radius.
Chemical Composition (ASTM B209)
| Element | Weight % |
|---|---|
| Silicon | 0.60 max |
| Iron | 0.70 max |
| Copper | 0.05-0.20 |
| Manganese | 1.00-1.50 |
| Zinc | 0.10 max |
| Others, each | 0.05 max |
| Aluminum | Remainder |
Mechanical Properties (thickness dependent)
| Temper | Tensile Strength (MPa) | Yield Strength 0.2% (MPa) | Elongation |
|---|---|---|---|
| 3003-H26 | 170-215 | 145 min | 3% min |
| 3003-H14 (reference) | 140-180 | 115 min | 4-8% |
| 3003-O (reference) | 95-130 | 35 min | 20-25% |
Values vary with gauge and follow the ranges published in ASTM B209; the H26 temper provides the highest dent and scratch resistance of the common sheet tempers.
Dimensional Tolerances (typical, per ASTM B209)
| Nominal Thickness (mm) | Width below 1000 mm | Width 1000-1250 mm | Width 1250-1500 mm |
|---|---|---|---|
| 0.50-1.20 | +/-0.05 | +/-0.06 | +/-0.08 |
| 1.21-2.00 | +/-0.08 | +/-0.09 | +/-0.10 |
| 2.01-3.00 | +/-0.10 | +/-0.12 | +/-0.14 |
| 3.01-5.00 | +/-0.15 | +/-0.18 | +/-0.20 |
Typical Applications of 3003-H26 Sheet
Transportation: trailer side panels, truck boxes, toolboxes, and floor liners that need dent resistance.
Architecture: metal roofing, exterior cladding, flashings, and weather strips.
HVAC: ducting, heat-exchanger fins, and equipment enclosures.
Manufacturing: general sheet-metal fabrication, protective covers, and guards for outdoor machinery.
For international trade, 3003 alloy sheet is classified under HS code 7606.12 (aluminum alloy rectangular plates and sheets over 0.2 mm thick).
Fabrication Notes
3003-H26 can be bent on a standard press brake when the inside radius is at least 2-3 times the sheet thickness. It must not be specified for deep drawing or complex stamping; for those operations use 3003-O or H14. The alloy welds readily with 4043 or 5356 filler, and because it is non-heat-treatable, welding does not require post-weld heat treatment to restore corrosion resistance, though the HAZ will soften toward the annealed condition. Continuous service temperatures should stay below about 150 °C, above which strength declines; at sub-zero temperatures the alloy remains ductile, which suits refrigeration equipment.
Frequently Asked Questions
What does H26 mean in 3003-H26? H26 means the sheet was strain hardened by cold rolling and then partially annealed to a 3/4-hard condition, balancing strength and remaining ductility.
Is 3003-H26 heat treatable? No. 3003 is a non-heat-treatable Al-Mn alloy; its strength comes from cold working (H tempers), and annealing (O temper) restores softness and ductility.
Can 3003-H26 be deep drawn? No. The 3/4-hard temper lacks the elongation for deep drawing. Choose 3003-O or H14 for drawn or heavily formed parts.
What is the difference between 3003-H26 and 3003-H14? H26 is about 3/4 hard with higher tensile strength and stiffness; H14 is half hard with better formability. H26 suits panels, H14 suits bends and drawn parts.
What is the maximum service temperature for 3003? Continuous service above roughly 150 °C progressively reduces mechanical strength, so design loads assume cooler service unless the annealed temper is accepted.
Which standards cover 3003 aluminum sheet? ASTM B209 in North America, EN 485-2 / EN 573-3 in Europe, JIS H4000 (A3003) in Japan, and GB/T 3880 in China. Need 3003-H26 sheet or slit coil in 4x8 ft or custom sizes? Our mill supplies material test certificates to EN 10204 3.1 with every order. Request your quotation today.
