Aluminum EN AW-3003: Composition, Properties, Temper Guide & Applications

Comprehensive Overview

EN AW-3003 is a member of the 3xxx series of wrought aluminum alloys, an aluminum-manganese family designed around moderate strength and superior corrosion resistance. The 3xxx series derives its principal strengthening element from manganese additions, typically about 1.0–1.5 wt%, which produces a uniform dispersion of intermetallic particles and provides solid-solution strengthening and grain refinement without relying on precipitation hardening.

3003 is a non-heat-treatable, strain-hardenable alloy; strengthening is achieved by cold work rather than thermal precipitation. Key traits include good moderate strength, excellent formability in annealed tempers, very good corrosion resistance in atmospheric environments, and wide compatibility with common welding processes.

Industries that frequently use EN AW-3003 include building and construction for roofing and cladding, consumer appliances and cookware, HVAC ducting, chemical handling where aggressive pitting is not expected, and general sheet metal fabrication. Engineers select 3003 when a combination of low cost, good formability, and reasonable strength is required and when the superior galvanic or pitting resistance of higher-alloyed systems is not necessary.

Temper Variants

Temper	Strength Level	Elongation	Formability	Weldability	Notes
O	Low	High	Excellent	Excellent	Fully annealed, best for deep drawing and forming
H12	Moderate	Moderate	Good	Excellent	Partial strain-hardening for moderate stiffness
H14	Moderate-High	Moderate	Good	Excellent	Common cold-worked temper for sheet applications
H16	High	Low-Moderate	Fair	Excellent	More heavily strain-hardened for higher yield
H18	Very High	Low	Poor-Fair	Excellent	Maximum strain-hardening by cold work
H22 / H24	Moderate	Moderate	Good	Excellent	Cold worked and partially annealed; balance of form and strength

Temper has a first-order impact on the mechanical balance between strength and ductility because 3003 is strengthened by strain hardening rather than age hardening. Annealed (O) product offers the best formability for deep drawing and complex bends, while H-series tempers trade elongation for higher yield and tensile strength useful for structural panels and stiffeners.

Chemical Composition

Element	% Range	Notes
Si	0.0 – 0.6	Impurity from processing; small amounts reduce fluidity in casting but limited effect in wrought products
Fe	0.0 – 0.7	Forms intermetallics that can reduce ductility in high concentrations
Mn	1.0 – 1.5	Primary alloying element providing strengthening and corrosion resistance
Mg	0.0 – 0.2	Small amounts may increase strength slightly; high Mg not present in 3003
Cu	0.05 – 0.20	Minor additive; improves strength modestly but can reduce corrosion resistance if excessive
Zn	0.0 – 0.10	Trace amounts only
Cr	0.0 – 0.05	Trace element to control grain structure in some specifications
Ti	0.0 – 0.15	Often present as grain refiner in small amounts
Others	Balance Al + residuals	Typical trace impurities and intentional microalloying elements

The alloy chemistry centers on manganese as the main strength and corrosion-resistance contributor, with copper and iron kept low to moderate to preserve ductility and limit intermetallic formation. Small additions of Ti or Cr can be used to control grain size in processing, while Si and Fe are controlled to limits to avoid adverse effects on formability and surface quality.

Mechanical Properties

Tensile behavior of EN AW-3003 is characteristic of a cold-worked, ductile aluminum alloy. In annealed condition the alloy exhibits relatively low yield and tensile strengths but high uniform elongation suitable for deep drawing. Cold-working to H-series tempers raises yield and tensile strength substantially while reducing total elongation and increasing hardness through dislocation multiplication and strain aging.

Yield strength and tensile strength vary with temper and thickness; thinner gauges typically achieve somewhat higher strengths after strain hardening due to work-hardening effects during rolling and forming. Hardness correlates with temper and cold work; Brinell or Vickers hardness measurements show a progressive increase from the O temper to H18. Fatigue performance is moderate and is influenced more by surface finish, thickness, and forming-induced residual stresses than by composition alone.

Property	O/Annealed	Key Temper (H14/H16)	Notes
Tensile Strength (Rm)	≈ 80–120 MPa	≈ 150–220 MPa	Values vary with thickness and specific H temper
Yield Strength (0.2% Rp0.2)	≈ 35–60 MPa	≈ 120–170 MPa	Cold work raises yield significantly
Elongation (A50)	≈ 20–35%	≈ 2–12%	Annealed has high formability; H tempers have reduced ductility
Hardness (HB)	≈ 20–35 HB	≈ 40–60 HB	Hardness rises with degree of strain hardening

Physical Properties

Property	Value	Notes
Density	2.73 g/cm³	Typical for wrought Al–Mn alloys
Melting Range	~640–655 °C	Solidus to liquidus approximate range
Thermal Conductivity	~130–150 W/m·K	Lower than pure Al due to alloying; excellent for heat spreading
Electrical Conductivity	~30–40 % IACS	Reduced versus commercially pure Al because of Mn and other solutes
Specific Heat	~900 J/kg·K	Typical for aluminum alloys near room temperature
Thermal Expansion	~23.0–24.0 µm/m·K	Coefficient of linear thermal expansion (20–100 °C)

The physical properties make EN AW-3003 suitable where heat transfer and weight are important but where the highest possible electrical conductivity is not required. Thermal conductivity is high enough for many heat-sinking and HVAC applications while the moderate coefficient of thermal expansion must be considered for multi-material assemblies to avoid differential movement.

Product Forms

Form	Typical Thickness/Size	Strength Behavior	Common Tempers	Notes
Sheet	0.2 – 6 mm	Forms and work-hardens predictably	O, H14, H16	Most common form for appliance panels, roofing, cladding
Plate	6 – 25 mm	Lower formability, higher stiffness	O, H12, H14	Used for structural panels and fabricated enclosures
Extrusion	Custom profiles	Strength depends on section and cold work	O, H14	Limited compared with 6xxx alloys; used where form and corrosion matter
Tube	0.4 – 6 mm wall	Good weldability and forming	O, H14	HVAC ducting, fuel lines in non-critical environments
Bar/Rod	Ø3 – Ø50 mm	Limited to non-heat-treatable strengthening	O, H14, H16	Cold heading and machining stock for fittings and fasteners

Different product forms reflect downstream processing and application demands: sheet and plate are rolled and supplied in a variety of tempers optimized for forming or strength, while extrusions and tubes require attention to die design and post-extrusion cooling to control properties. Thicker sections will not cold work as uniformly as thin gauge material and may need pre- or post-processing anneals to achieve targeted ductility.

Equivalent Grades

Standard	Grade	Region	Notes
AA	3003	USA	Common designation in ASTM/AA standards
EN AW	3003	Europe	Equivalent wrought alloy under EN nomenclature
JIS	A3003	Japan	JIS systems reference A3003 as the close counterpart
GB/T	3A21	China	Chinese designation equivalent to 3003 in many specifications

Equivalent grades across standards are based on broadly similar chemistry and performance but permissible ranges and required tests may differ. Buyers should check specific standard sheets for limits on impurities, required tempers, and testing protocols since these small differences can affect surface finish, stamping performance, and certification for regulated applications.

Corrosion Resistance

EN AW-3003 exhibits good general atmospheric corrosion resistance due to the passive aluminum oxide film and the relatively benign effect of manganese as the primary alloying element. It performs well in indoor and rural/urban exposures and resists mild industrial atmospheres where sulfur compounds are not aggressive.

In marine or chloride-bearing environments 3003 performs acceptably for many secondary marine components but is not as resistant to pitting and crevice corrosion as aluminum-magnesium 5xxx series alloys. For primary marine structural components or highly chloride-exposed details, 5xxx-class alloys (e.g., 5083, 5052) or protective coatings are usually preferred.

Stress corrosion cracking susceptibility for 3003 is low because its maximum achievable strengths are modest compared with high-strength heat-treatable alloys; however, localized galvanic corrosion can be a concern when mated to more noble metals such as copper or stainless steels without appropriate isolation. Proper material selection and isolation techniques reduce the risk of galvanic attack in mixed-metal assemblies.

Fabrication Properties

Weldability
EN AW-3003 is readily welded using standard fusion methods such as GTAW (TIG) and GMAW (MIG) with low risk of hot-cracking. Common filler alloys include ER4043 (Al–Si) and ER4047 for better fluidity, and ER5356 (Al–Mg) where higher weld strength is desired; selection depends on joint design and post-weld corrosion considerations. Heat-affected zones will show localized softening relative to cold-worked parent material but no precipitation-hardening-related embrittlement because the alloy is non-heat-treatable.

Machinability
Machining of 3003 is moderate compared with free-machining aluminum alloys; its machinability index is lower than Al–Cu or Al–Si bearing alloys due to ductile chips and a tendency for built-up edge formation. Carbide tooling with sharp geometry, positive rake, and adequate lubrication/coolant is recommended, and spindle speeds should be set to avoid smearing and to promote chip breakage. Drilling and tapping require appropriate peck cycles and chip evacuation for deep holes.

Formability
Formability is one of the strongest attributes of 3003, especially in the fully annealed O temper where deep drawing, stretching, and complex bending are achievable without cracking. Minimum bend radii are commonly on the order of 1–2 times material thickness for O temper, but are increased for H-series tempers as ductility decreases; designers should validate forming radii for specific gauges and geometries. Work hardening increases strength but limits subsequent forming operations; intermediate anneals are commonly used for severe forming sequences.

Heat Treatment Behavior

EN AW-3003 is not responsive to solution heat treatment and artificial aging because it lacks significant precipitation-hardening elements; it is classified as non-heat-treatable. Thermal annealing in the range of approximately 350–450 °C is used to fully recrystallize and restore ductility after cold work, with soak times and cooling rates controlled to avoid distortion and to maintain surface quality.

Work hardening is the principal mechanism for property modification: controlled cold deformation produces H-series tempers with predictable increases in yield and tensile strength. Temper transitions follow standard designations (e.g., O → H14) achieved by specified degrees of cold work or by partial annealing to reach intermediate tempers such as H22/H24.

High-Temperature Performance

At elevated temperatures EN AW-3003 loses strength progressively as thermal activation allows dislocation motion and recovery; significant strength reduction becomes apparent above ~125–150 °C for prolonged service. Oxidation is limited to the formation of a stable aluminum oxide layer and is typically not a limiting factor for modest temperature exposures, but long-term high-temperature exposure will degrade mechanical properties and dimensional stability.

Weld zones and heavily worked areas can exhibit thermal softening during service at elevated temperatures; designers should consider creep and relaxation effects for sustained loads at elevated temperatures and prefer higher temperature-rated alloys for continuous service above the 100–150 °C range.

Applications

Industry	Example Component	Why EN AW-3003 Is Used
Automotive	Heat shields, trim, HVAC ducts	Good formability, corrosion resistance, cost-effective
Marine	Non-structural panels, interior components	Corrosion resistance in atmospheric marine environments
Aerospace	Fittings, fairings (non-structural)	Good strength-to-weight for secondary components
Electronics	Heat spreaders, housings	Good thermal conductivity combined with formability
Consumer Appliances	Cookware, refrigerator panels	Surface finish, formability, and corrosion resistance

EN AW-3003 is favored for applications where a balance of low cost, manufacturability, and corrosion resistance is required but where the highest structural strength is not essential. Its versatility across sheet, tube, and formed parts makes it a staple material for many fabricators and OEMs.

Selection Insights

EN AW-3003 is selected when moderate strength, excellent formability, and good atmospheric corrosion resistance are primary requirements and when cost and availability are important. Choose the O temper for complex forming and deep drawing, and H-series tempers when increased stiffness or yield is required for fabricated parts.

Compared with commercially pure aluminum (1100), 3003 offers significantly higher strength at the expense of slightly reduced electrical and thermal conductivity; use 1100 when maximum conductivity and softness are critical. Compared with 5xxx series alloys such as 5052, 3003 trades some chloride/pitting resistance and stronger performance for easier formability and usually lower material cost, making 3003 preferable for general-purpose forming and cladding. Versus heat-treatable alloys such as 6061 or 6063, 3003 provides better cold formability and lower cost, but lower peak strength; prefer 3003 when forming complexity and corrosion take priority over peak mechanical properties.

Closing Summary

EN AW-3003 remains a widely used, practical aluminum alloy for modern engineering due to its combination of good formability, acceptable strength after cold work, excellent weldability, and reliable corrosion resistance for many environments. Its balance of properties and cost-effectiveness make it a first-choice material for HVAC, appliances, architectural cladding, and general sheet metal fabrication where ultimate tensile strength is not the primary design driver.