3A21 Aluminum Bar
3A21 aluminum bar is a wrought aluminum-manganese alloy belonging to the 3000 series, renowned for its excellent corrosion resistance, good formability, and moderate strength. The primary alloying element, manganese, enhances strength while maintaining workability, making 3A21 a preferred material for applications requiring durability combined with ease of fabrication. With a chemical composition typically comprising approximately 96.8–99.0% aluminum and 1.0–1.6% manganese, this alloy strikes a balance between mechanical performance and processability.
Due to its stable metallurgical structure, 3A21 aluminum rod bar retains good dimensional stability during forming, bending, deep drawing, and spinning operations. It also exhibits excellent weldability using common techniques such as TIG, MIG, and resistance welding, producing joints with comparable corrosion resistance to the base metal. Machinability is favorable, though chip formation may require optimized tooling compared to free-cutting alloys. Electrical and thermal conductivity remain relatively high, close to commercially pure aluminum, making it useful in certain conductive applications.
Advantage |
Explanation |
Typical Benefit |
| Excellent Corrosion Resistance | Mn addition and Al–Mn matrix inhibit rust; suitable for humid and mildly aggressive environments | Long service life with minimal protective coatings in tanks, piping, and outdoor parts |
| High Plasticity and Formability | Very ductile in the annealed (O) state; well-suited to bending, deep drawing, and complex shaping | Enables thin-wall and intricate parts with consistent quality |
| Good Weldability | Compatible with common fusion and resistance welding; post-weld corrosion resistance remains close to base metal | Reliable joints in tanks, ducts, and structural assemblies |
| Cold-Work Strengthening | Strength is increased by cold working; no quench/cure cycles needed | Simpler processing routes and dimensional control via cold drawing/rolling |
| Good Machinability in O/H112 | Responds well to machining; dimensional control achievable for rods, bars, and profiles | Efficient production of bolts, fittings, and custom components |
Our 3A21 aluminum rod bar meet or exceed international standards, including ASTM B221, ASTM B211, EN 573 / EN 755, GB/T 3191. Our quality management system ensures compliance with these standards and provides reliable, certified materials for your critical applications.
HSTF Aluminum is a high-quality 3A21 aluminum rod bar supplier and manufacturer in China. We have large stock, factory direct price, quality assurance, fast delivery.
Specification
| Alloy | 3A21 (also known as 3003 equivalent in some standards; Al-Mn alloy) |
| Chemical Composition | Al ≥ 96.8%, Mn 1.0–1.6%, Fe ≤ 0.7%, Si ≤ 0.6%, Cu ≤ 0.05%, Zn ≤ 0.1%, Other each ≤ 0.05%, Total others ≤ 0.15% |
| Temper Options | O (annealed), H14 (strain hardened, half hard), H18 (strain hardened, full hard), H24, H26 |
| Form | Solid round bar, square bar, hexagonal bar, rectangular bar |
| Production Process | Hot extrusion, cold drawing, hot rolling, cold rolling |
| Diameter / Section Size | Round bar: 5 mm–350 mm; Square bar: 5 mm–250 mm; Hexagonal bar: 5 mm–120 mm; Rectangular bar: width 10–300 mm × thickness 5–150 mm |
| Length Range | 1 m–6 m standard; custom lengths available |
| Tolerance (Dimensions) | Standard ±0.1 mm–±0.5 mm; precision ±0.05 mm–±0.2 mm |
| Length Tolerance | ±2 mm standard; precision ±1 mm |
| Density | 2.73 g/cm³ |
| Tensile Strength | O temper: 110–130 MPa; H14: 140–170 MPa; H18: 185–215 MPa |
| Yield Strength | O temper: 40–55 MPa; H14: 115–145 MPa; H18: 165–195 MPa |
| Elongation at Break | O temper: 23–30%; H14: 5–12%; H18: 2–6% |
| Hardness (HV) | O temper: 28–35 HV; H14: 45–60 HV; H18: 70–85 HV |
| Elastic Modulus | ~70 GPa (10.2×10⁶ psi) |
| Electrical Conductivity | 40–50% IACS (International Annealed Copper Standard) |
| Thermal Conductivity | 120–160 W/m·K |
| Melting Range | 643–654 °C |
| Packing | Moisture-resistant wrapping, VCI paper interleaving, strapped bundles, wooden pallets/crates for export protection |
Application
Chemical Processing Equipment: 3A21 aluminum bar is widely used in tanks, pipes, fittings, and reaction vessels handling chemicals, thanks to its corrosion resistance and ease of fabrication.
Architectural & Building Components: Curtain wall frames, decorative trims, handrails, and signage benefit from the alloy’s weather resistance and attractive surface finish options.
Heat Exchangers & Radiators: Its good thermal conductivity and corrosion resistance make it ideal for fins, tubes, and structural supports in HVAC and refrigeration systems.
Automotive Components: Fuel lines, brackets, heat shields, and decorative panels take advantage of the alloy’s light weight and corrosion resistance.
General Fabrication & Engineering: Machined parts, brackets, couplings, and structural members in industrial machines and consumer goods.
Marine Hardware (non-critical load-bearing): Deck fittings, railings, and housings in marine environments benefit from excellent saltwater corrosion resistance.
Package
| Packing | 1,Generaally package:Anti-water paper+strapped with min three strapping strips. |
| 2,Standard exporting package:Anti-water paper and plastic+covered by iron shrrt+strapped with min three strapping strips. | |
| 3,Excellent package:Anti-water paper and plastic film+covered by iron sheet+strapped with min three strapping strip+fixed on the iron or wooden pallets by strapping strips. | |
| Shipping | 1,Shipping by containers |
| 2,Shipping by bulk ship | |
| Custom | Customization is available upon request |
Why Choose Us?
Quality Assurance – All products comply with ASTM, EN, ISO and other international standards, ensuring high purity, uniformstructure, and stable performance.
Professional Supplier – Professional 3A21 aluminum bar rod supplier in China. We have an advanced factory to ensure quality and efficiency.
Competitive Price – The mature supply chain system, advanced equipment and technology ensure that our products are highly competitive in cost and price.
Superior Quality – Quality supervision on whole process of production from raw materials, manufacturing, packaging, warehousing till container loading.
On-Time Delivery – The mature logistics management system and company self owned freight forwarder ensure that our OTD rate reaches 100%.
FQA
Yes,we promise to provide best quality products and delivery on time .Honesty is our company’s tenet.
We can provide the sample for customer with free, but the customer account will cover the courier freight.
The manufacturing process produces each piece in certified workshops. Our inspection team checks them piece by piece. This is done according to national QA/QC standards. We also could issue the warranty to customer to guarantee the quality.
We specialize in steel business for years. Our headquarters is in Liaocheng Economic Zone. This is in Shandong province. You are welcome to investigate in any way. By all means, you could place an order. Use trade assurance for your payment security.
Our team will check email and fax within 24 hours. Meanwhile, these platforms remain online 24 hours. They include Facebook, Skype, WeChat, and WhatsApp. Please send us your requirements and order information. Provide the specification details. These include steel grade, size, and quantity. Also include the destination port. We will work out the best price soon.
