3003-O/H14/H22 Aluminum Square Tube

What Is 3003 Aluminum Square Tube?

3003 aluminum square tube is a hollow extruded profile with a square cross-section, made from the 3003 alloy — a manganese-strengthened, non-heat-treatable aluminum alloy. With approximately 1.0–1.5% Mn, it offers 10–20% higher strength than commercial-pure aluminum (1100/1060) while retaining excellent corrosion resistance, weldability, and formability. The square tube form provides uniform bending stiffness in both directions, making it suitable for structural frameworks, enclosures, and decorative trim where a clean rectangular profile is preferred.

In tube products, 3003 is commonly supplied in strain-hardened tempers (H12, H14, H16, H22, H24) as well as the fully annealed O temper. All tempers are non-heat-treatable — strength is gained through cold working, not precipitation hardening. This makes 3003 square tube easy to bend, weld, and fabricate without concern for heat-treatment distortion after welding.

Available 3003 Aluminum Square Tube Products

3003-O Square Tube (Annealed)

The O temper offers the lowest strength and highest ductility. It is the right choice when severe bending, flaring, or expansion is required during installation. Tensile strength ranges from 75 to 130 MPa, and elongation exceeds 30%, allowing complex forming operations without cracking. Typical uses include decorative trim, conduit, and ductwork that requires in-field bending.

3003-H14 Square Tube (Half-Hard)

H14 is the most commonly stocked temper for 3003 square tube. It balances moderate strength (tensile 115–180 MPa, yield ≥ 50 MPa) with sufficient ductility for standard fabrication. H14 tube is suitable for general-purpose structural frames, equipment enclosures, and furniture where some forming is still needed but higher stiffness is desired over the O temper.

3003-H22 Square Tube (Quarter-Hard)

H22 temper provides slightly lower strength than H14 but retains more formability. Tensile strength falls in the 95–155 MPa range. It is often specified when moderate bending or roll-forming is required after delivery, but the finished part still needs to carry light loads.

3003 Square Tube — Size & Weight Reference

Below is a representative selection of common cross-section sizes. Custom dimensions outside this range are available on request.

Outer Side (mm)	Wall Thickness (mm)	Approx. Weight (kg/m)	Standard Length
10	1.0	0.10	1000–6000
15	1.0	0.16	1000–6000
15	1.5	0.23	1000–6000
20	1.0	0.21	1000–6000
20	1.5	0.31	1000–6000
25	1.5	0.39	1000–6000
25	2.0	0.51	1000–6000
30	1.5	0.48	1000–6000
30	2.0	0.63	1000–6000
40	2.0	0.86	1000–6000
40	3.0	1.24	1000–6000
50	2.0	1.08	1000–6000
50	3.0	1.57	1000–6000
60	2.0	1.30	1000–6000
60	3.0	1.91	1000–6000
80	2.5	2.20	1000–6000
80	3.0	2.61	1000–6000
100	3.0	3.28	1000–6000
100	4.0	4.27	1000–6000

Notes: Weights are approximate, calculated at density 2.73 g/cm³. Standard lengths are 1–6 m; custom lengths and wall/side combinations outside the above table are available with typical lead times of 10–60 days.

Specifications & Equivalent Designations

Specification	Detail
UNS Designation	A93003
EN Designation	EN AW-3003 (AlMn1Cu)
DIN Material Number	3.0517
Primary Standard	ASTM B221 (Aluminum Alloy Extruded Tubes)
Chinese Standard	GB/T 6893
JIS Standard	H 4080
Series	3xxx (Mn-strengthened, non-heat-treatable)

Chemical Composition

Per ASTM B221 / GB/T 3190, the composition of 3003 alloy is:

Element	Content (%)
Si	0.6 max
Fe	0.7 max
Cu	0.05–0.20
Mn	1.0–1.5
Mg	0.05 max*
Zn	0.10 max
Others: Each	0.05 max
Others: Total	0.15 max
Al	Balance

* Mg limit applies when Mn is below 1.0%; otherwise Mg is not separately specified in some references. Verify against the specific standard edition governing your purchase order.

Mechanical Properties by Temper

The following values represent typical ranges for 3003 aluminum tube per ASTM B221. Actual properties depend on wall thickness and production lot; always confirm with the MTC provided with your order.

Temper	Tensile Strength (MPa)	Yield Strength (MPa)	Elongation (%)
O	75–130	≤ 40	≥ 30
H12	95–155	≥ 35	≥ 12
H14	115–180	≥ 50	≥ 8
H16	135–200	≥ 70	≥ 5
H22	95–155	≥ 30	≥ 16
H24	115–180	≥ 40	≥ 10

Key point: In strain-hardened tempers (H1x), the number after H indicates the degree of cold work: H12 & H22 → quarter-hard, H14 & H24 → half-hard, H16 → three-quarter-hard. H2x tempers are strain-hardened then partially annealed, providing similar strength to H1x with improved ductility.

Temper Selection Guide

Choosing the right temper for your 3003 square tube depends on the fabrication demands and the in-service load requirements:

Temper	Best For	Formability	Strength
O	Severe bending, flaring, expansion	Highest	Lowest
H12 / H22	Moderate forming with light load-carrying	Good	Low–Moderate
H14 / H24	General fabrication, structural frames, enclosures	Fair	Moderate
H16	High stiffness, minimal post-forming	Low	Higher

For most general-purpose square tube orders, H14 is the default temper stocked by Linsy. If your project requires significant bending after delivery, request O or H22.

Key Characteristics

Corrosion Resistance

3003 alloy resists atmospheric, freshwater, and mild chemical corrosion well, thanks to the manganese addition which stabilizes the aluminum oxide layer. It is widely used in chemical processing, marine splash-zone trim, and food-contact equipment where long-term corrosion resistance matters. For aggressive saltwater immersion, consider 5083 or 5052 which offer higher marine-grade performance.

Formability & Weldability

3003 is one of the easiest aluminum alloys to form and weld. In the O temper, it can be bent to tight radii without cracking. All tempers can be joined by TIG and MIG welding using 4043 or 5356 filler wire. Because 3003 is non-heat-treatable, weld zones do not lose strength through precipitation dissolution — the only strength reduction is local annealing in the heat-affected zone, which can be mitigated by using strain-hardened base metal away from the weld.

Moderate Strength

With Mn providing roughly 20% strength gain over pure aluminum, 3003 square tube is adequate for light structural loads, equipment framing, and decorative applications. It is not intended for heavy-load bearing. If your design requires higher structural strength (tensile ≥ 240 MPa), 6061-T6 or 6063-T5 are more appropriate alternatives within the 6xxx series.

Applications

• Chemical processing equipment frames and conduit
• Ductwork and ventilation systems
• Storage tank reinforcement and trim
• General sheet metal frameworks
• Food and beverage container supports
• Marine trim and splash-zone components
• Light structural frameworks for signage and enclosures
• Furniture frames and decorative architectural trim

Processing & Surface Finish Notes

3003 square tube is straightforward to process:

• Cutting: Saw cutting, laser cutting, and CNC mill cutting are all suitable. Wall thickness up to 4 mm can be cleanly laser-cut.
• Bending: O and H22 tempers bend easily. H14 requires larger bend radii (minimum ≥ 2–3× outer side length). H16 should be avoided for tight bends.
• Welding: TIG and MIG welding with ER4043 or ER5356 filler. No pre- or post-weld heat treatment needed. HAZ reverts toward O temper locally.
• Surface finishes: Mill finish (standard), anodizing (clear or colored for architectural use), powder coating, polishing, and PVC-film protective wrapping during transit.

For precision-cut or bent square tube, provide drawings with tolerances. Linsy can CNC-cut to length ±1 mm and bend to specified radii on request.

Quality Documents & Inspection

Every order of 3003 aluminum square tube from Linsy is accompanied by:

• Mill Test Certificate (MTC) — confirms chemical composition, mechanical properties, and temper for each production lot
• Dimensional inspection report — outer side, wall thickness, straightness, and length measured per ASTM B221 tolerance classes
• SGS third-party test report — available on request for buyers requiring independent verification

Linsy operates under ISO 9001 (quality management), ISO 14001 (environmental), and ISO 45001 (occupational health & safety) certified systems. SGS test reports are third-party verification documents, not company certifications.

Why Choose Linsy for 3003 Square Tube

Linsy Aluminum is a Shenzhen-based factory with over 20 years of experience supplying 1000–8000 series aluminum products, including tube, bar, sheet, coil, wire, and profile. For 3003 square tube specifically:

• Temper flexibility: O, H12, H14, H16, H22, H24 available
• Size range: Outer side 10–100 mm, wall 0.8–5 mm, custom sizes on request
• Custom lengths: Cut to length or standard 1–6 m bars; typical lead time 10–60 days for custom specifications
• MTC included: Every shipment carries a Mill Test Certificate
• Global delivery: Exported to 20+ countries with competitive freight

Whether you need a few lengths for a prototype or a production run for an OEM project, Linsy can accommodate your order size and delivery schedule.

Related Resources

For deeper technical background on 3003 alloy and comparisons with alternatives:

• A Comprehensive Guide to 3003 Aluminium Alloy
• Guide to 3003 H14 Aluminum — Properties, Tempers, and Uses
• 3104 vs 3003 vs 3004 Aluminum — Which Sheet Alloy Fits Your Project?
• 3003 vs 6061 Aluminum — In-Depth Comparison

3003 Aluminum Square Tube FAQ

What sizes of 3003 square tube does Linsy supply?

Standard outer side dimensions range from 10 mm to 100 mm with wall thickness from 0.8 mm to 5 mm. Custom cross-section sizes outside this range can be produced with typical lead times of 10–60 days.

Can 3003 square tube be welded?

Yes. 3003 has excellent weldability using TIG or MIG methods. Recommended filler wires are ER4043 (for general welding) or ER5356 (when higher weld strength is needed). Since 3003 is non-heat-treatable, there is no strength loss from precipitation dissolution in the weld zone.

Is 3003 square tube suitable for marine use?

3003 offers good resistance to freshwater and mild atmospheric corrosion. For full saltwater immersion or splash-zone service, 5083 or 5052 alloys are more appropriate due to their higher magnesium content and marine-grade performance.

What is the difference between H14 and H24 temper?

H14 is strain-hardened to half-hard condition directly from cold working. H24 is strain-hardened then partially annealed. Both reach similar tensile strength (~115–180 MPa), but H24 retains slightly more ductility (elongation ≥ 10% vs ≥ 8%) because the partial anneal relaxes internal stresses without fully reverting to O temper.

What tolerances apply to 3003 square tube dimensions?

Per ASTM B221, typical tolerances for extruded aluminum tube are: outer side ±0.25 mm (for sizes ≤ 50 mm) and wall thickness ±10% of nominal. Straightness tolerance is typically 1.5 mm per 3 m length. Tighter tolerances can be negotiated for custom orders.

General Ordering FAQ

What is the minimum order quantity (MOQ)?

Linsy supports low MOQs for trial orders. For standard sizes and tempers from existing stock, MOQs are typically a few hundred kilograms. For fully custom specifications, MOQs may be higher — contact our team for your specific requirement.

How long does delivery take?

Standard sizes from available stock: 7–15 business days (domestic) or 15–30 business days (international). Custom specifications: typical lead time 10–60 days depending on size, temper, and quantity.

What quality documents come with my order?

Every order includes a Mill Test Certificate (MTC) confirming chemical composition, mechanical properties, and temper. SGS third-party test reports are available on request for buyers needing independent verification.

Can Linsy cut or bend square tube to my specifications?

Yes. Linsy offers CNC cutting to length (±1 mm tolerance), bending to specified radii, and surface finishing (anodizing, powder coating, polishing). Provide your drawings or specifications and our engineering team will confirm feasibility and lead time.