Aluminum 3005: Composition, Properties, Temper Guide & Applications

Comprehensive Overview

3005 is a member of the 3xxx series of wrought aluminum alloys, where manganese is the principal alloying element. The alloy typically contains modest additions of magnesium to provide a balance of increased strength and improved work-hardening response compared with 3003 and similar alloys.

The alloy is non-heat-treatable and derives its strength primarily from cold working (strain hardening) and microalloying with Mn/Mg. This means designers rely on tempering (H‑tempers) and mechanical processing rather than solution/aging cycles to change mechanical properties.

Key traits of 3005 include moderate strength, very good corrosion resistance in many atmospheric environments, excellent formability in softer tempers, and generally good weldability with common aluminum filler metals. Typical industries using 3005 are architectural cladding and gutters, automotive body panels and trim, HVAC ducting, consumer appliances, and certain marine and transportation exterior panels where moderate strength and good surface appearance are required.

Engineers select 3005 when a balance of improved strength over pure Al (1000 series) and 3003 is needed without sacrificing much formability or incurring the higher cost and different processing of heat-treatable alloys. The alloy is chosen over higher-strength families when large-area forming, paintability, and corrosion resistance are priorities over maximum specific strength.

Temper Variants

Temper	Strength Level	Elongation	Formability	Weldability	Notes
O	Low	High (≥20%)	Excellent	Excellent	Fully annealed, maximizes ductility and drawability
H12	Low–Medium	High–Medium (~15–20%)	Very Good	Very Good	Light strain hardening, good for medium forming
H14	Medium	Medium (~10–15%)	Good	Very Good	Quarter‑hard; common for applications needing balance of formability and strength
H16	Medium–High	Medium (~8–12%)	Fair–Good	Good	Half‑hard; improved stiffness for panels
H18	High	Low–Medium (~4–8%)	Fair	Good	Full‑hard; used where higher strength and springback resistance are needed
H22 / H24	Medium–High	Medium (~8–12%)	Good–Fair	Good	Strain‑hardened then partially annealed (H24); tailored balance of ductility and strength
T5 / T6 / T651	N/A (not applicable)	N/A	N/A	N/A	Heat‑treatable tempers generally not applicable to 3005 (non‑heat‑treatable alloy)

Temper strongly controls the tradeoff between ductility and strength in 3005: softer O and light H‑tempers enable deep drawing and stretching, while H16–H18 provide higher yield and improved panel stability. Because 3005 is not heat‑treatable, designers must specify mechanical tempers and cold working sequences to reach target properties rather than relying on aging cycles.

Chemical Composition

Element	% Range	Notes
Si	≤ 0.6	Silicon controlled to limit casting/flow problems; small amounts tolerated
Fe	≤ 0.7	Iron is the common impurity; excessive Fe reduces ductility and surface finish quality
Mn	0.5 – 1.0	Primary strengthener in 3xxx series; controls grain structure and work‑hardening
Mg	0.3 – 0.7	Small Mg raises strength and improves strain hardening response
Cu	≤ 0.2	Low Cu minimizes susceptibility to intergranular corrosion
Zn	≤ 0.2	Zinc kept low to avoid excessive galvanic activity and maintain formability
Cr	≤ 0.1	Trace Cr may control recrystallization in some production routes
Ti	≤ 0.1	Titanium used in minute quantities as grain refiner in cast/ingot metallurgy
Others	≤ 0.15 each, ≤ 0.05 Bi/Pb/Sb	Residual elements and trace additions; Al remainder

The manganese and magnesium content are the principal determinants of 3005’s mechanical response. Mn forms dispersoids and stabilizes the grain structure during rolling and forming, while Mg contributes to solid solution strengthening and increases yield/ultimate strength without making the alloy heat-treatable. Control of iron and silicon is important for surface finish and bendability, particularly for painted architectural applications.

Mechanical Properties

Tensile behavior of 3005 is highly temper dependent and thickness sensitive. In annealed condition the alloy displays moderate tensile strength with long uniform elongation suitable for forming and deep drawing, while cold‑worked H‑tempers raise yield and tensile strength at the expense of ductility and formability.

Yield strength increases markedly with strain hardening; typical H14–H18 tempers are used when panel stiffness, flanging, and springback control are needed. Fatigue behavior is reasonable for low‑to‑moderate cyclic loads; fatigue life is strongly influenced by surface finish, forming breaks, and local stress concentrators introduced during fabrication.

Hardness follows the same trend as strength and is commonly measured on the Brinell or Vickers scales for quality control. Thickness effects are pronounced: thinner gauges can achieve higher room‑temperature formability and more uniform properties after cold working, while thicker sections show higher constraints on bend radii and lower uniform elongation.

Property	O/Annealed	Key Temper (H14 / H18)	Notes
Tensile Strength	100 – 150 MPa	180 – 260 MPa	Range depends on temper and thickness; H‑tempers nearly double tensile vs O in some conditions
Yield Strength	35 – 80 MPa	120 – 200 MPa	Yield rises rapidly with work hardening; specification control essential for formed parts
Elongation	18 – 30%	4 – 15%	Elongation falls as strength increases; design for forming should use O/H12/H14
Hardness (HB)	25 – 45 HB	60 – 95 HB	Hardness correlates with cold work; values vary with measurement technique and sample prep

Physical Properties

Property	Value	Notes
Density	2.73 g/cm³	Typical for wrought Al‑Mn alloys; useful for mass calculations
Melting Range	~643 – 654 °C	Alloy melting point range; solidus/liquidus influenced by impurities
Thermal Conductivity	~140 W/m·K (room temp)	Lower than pure Al due to alloying; still good for heat spreading
Electrical Conductivity	~35 – 45 % IACS	Reduced from pure Al; conductivity varies with temper and cold work
Specific Heat	~0.90 J/g·K	Typical for aluminum alloys near room temperature
Thermal Expansion	~23.6 µm/m·K (20–100 °C)	Comparable to other Al alloys; important for joined assemblies with dissimilar metals

3005 retains many of aluminum’s desirable physical attributes: low density, good thermal conduction, and high specific heat. Its thermal and electrical performance are lower than pure aluminum but remain acceptable for many thermal management and electrical grounding applications.

Designers must account for coefficient of thermal expansion when joining 3005 to steels or copper to avoid cyclic fatigue and seal failures. Thermal conductivity and specific heat values support its use in lightweight heat‑spreading panels and housings where absolute conductivity is less critical than weight and formability.

Product Forms

Form	Typical Thickness/Size	Strength Behavior	Common Tempers	Notes
Sheet	0.2 – 6.0 mm	Thickness influences formability; thinner gauges easier to draw	O, H12, H14, H16	Widest use in cladding, body panels, appliances
Plate	>6.0 mm	Reduced ductility; often used where added stiffness is needed	H16, H18	Limited availability in heavy plate; specialized production
Extrusion	Sectional profiles up to moderate sizes	Extruded sections can be aged or cold finished to raise strength	H14, H16	Less common than 6xxx extrusions; used for decorative trims
Tube	0.5 – 6 mm wall, various diameters	Welded or seamless tubing; weld HAZ and flattening behavior important	O, H14	HVAC ducts, architectural tubing, furniture frames
Bar/Rod	Diameters up to ~50 mm	Cold drawing increases strength; limited availability	H12, H14	Used for fasteners, pins, and formed components

Sheets and coils are the dominant product forms for 3005 because the alloy’s excellent formability and surface finish make it ideal for rolled products. Plate and heavier sections are less common and typically used where higher stiffness or thickness is required, although other aluminum series are often preferred for heavy structural plate.

Extrusion and tubular forms are produced when the profile or hollow section is needed; processing parameters (die design, extrusion speed, and cooling) must be adjusted for Mn/Mg alloys to control grain flow and surface quality. Post‑forming operations such as bending, hemming, and stretch forming are routine for sheet and coil in architectural and automotive supply chains.

Equivalent Grades

Standard	Grade	Region	Notes
AA	3005	USA	Aluminum Association designation; commonly cited in datasheets
EN AW	3005	Europe	EN AA‑3005 / EN AW‑3005 used in European standards and mill certificates
JIS	A3005 (approx)	Japan	Japanese standards may list close equivalents; always verify composition and temper
GB/T	3005 (approx)	China	Chinese standards have corresponding compositions; check national spec for tolerances

Equivalent naming conventions across standards generally point to the same base chemical composition, but regional standards can differ in tolerance, allowable impurities, and production test requirements. Engineers should always cross‑check mechanical property tables and mill test certificates rather than relying solely on nominal grade numbers when sourcing international material.

Corrosion Resistance

3005 exhibits good atmospheric corrosion resistance typical of the 3xxx series due to its stable oxide and moderate alloying levels. It performs well in urban and industrial environments and resists general corrosion and staining when painted or anodized.

In marine and chloride‑rich environments the alloy is serviceable for exterior trim and non‑critical structural panels but is not as robust as the 5xxx series (which contain higher Mg and offer superior resistance to pitting). Localized pitting can occur under concentrated chloride attack or in crevice conditions if protective coatings are compromised.

Stress corrosion cracking is not a major concern for 3005 under normal service conditions because the alloy is non‑heat‑treatable and lacks the microstructural predispositions that make some high‑strength alloys vulnerable. Galvanic interactions with dissimilar metals should be managed: aluminum is anodic relative to copper, stainless, and carbon steel and will corrode preferentially unless electrically isolated or protected by coatings and sealants.

Fabrication Properties

Weldability

3005 is readily welded with conventional TIG, MIG, and spot welding processes when using appropriate aluminum filler metals. Common filler choices include 4043 (Al‑Si) and 5356 (Al‑Mg) depending on required joint strength and corrosion resistance in service.

Hot‑cracking risk is low compared with some heat‑treatable alloys, but operators must control heat input and joint fit‑up to avoid excessive distortion and to minimize HAZ softening in heavily cold‑worked sections. Pre‑ and post‑weld mechanical properties should be considered for load‑bearing panels and flanged assemblies.

Machinability

Machinability of 3005 is moderate and generally more favorable than pure aluminum but below free‑machining brasses and some 6xxx series. Typical machining operations use high‑quality carbide or coated carbide tooling with moderate to high spindle speeds and positive rake angles to promote continuous chip formation.

Chip control is generally good when using rigid setups and flood or mist lubrication. Boring and threading are feasible in H‑tempers, but feed and speed must be optimized to avoid built‑up edge and surface smearing, particularly on thin‑walled parts.

Formability

Formability is one of 3005’s strong suits in softer tempers and thin gauges, enabling deep drawing, stretching, and complex bending operations. Minimum bend radii depend on temper and thickness; for O and H12 tempers designers can use tighter radii while H16–H18 require larger radius and more springback allowance.

Cold‑work response is predictable: controlled strain hardening sequences allow manufacturers to incrementally raise strength in formed features. For severe forming or complex geometry, specify O or light H‑tempers and consider intermediate anneals to restore ductility.

Heat Treatment Behavior

As a non‑heat‑treatable alloy, 3005 does not respond to solution heat treatment and artificial aging the way 6xxx and 7xxx series alloys do. Attempts to apply precipitation hardening cycles will not produce significant strengthening because the primary contributors to strength are Mn dispersoids and cold work.

Performance tuning is accomplished through mechanical work and annealing operations. Annealing (softening) is achieved by heating to appropriate temperatures followed by slow or controlled cooling to restore ductility; manufacturers commonly use full anneal (O) and partial anneal cycles to produce H24 and related tempers.

For process engineers the key thermal controls are avoiding over‑heating during welding and thermal processing that might coarsen dispersoids or cause unwanted grain growth. Controlled recrystallization via rolling and appropriate interanneals provides the microstructure necessary for consistent formability and surface finish.

High-Temperature Performance

Static strength of 3005 declines with temperature and long‑term exposure above roughly 100–150 °C; designers should limit continuous service temperatures and consult creep data for specific components. Short‑term exposure to higher temperatures is tolerated, but repeated thermal cycling can change dimensional stability and residual stress distributions.

Oxidation at elevated temperatures is minimal compared with steels, because aluminum forms a protective oxide film; however, oxide growth and scaling can affect paint adhesion and electrical contact surfaces. In welded structures the HAZ exhibits local softening and reduced yield, which reduces high‑temperature load capacity and may demand mechanical reinforcement or altered joint design.

Applications

Industry	Example Component	Why 3005 Is Used
Automotive	Exterior trim and body panels	Good balance of formability, surface finish, and moderate strength
Marine	Trim, non‑structural panels	Adequate corrosion resistance and paintability in coastal atmospheres
Aerospace	Interior fittings, fairings	Lightweight with good fabrication characteristics for non‑critical parts
Electronics	Shrouds and housings	Thermal spreading, EM shielding, and lightweight enclosure material
Building & Construction	Gutters, cladding, roofing	Weather resistance, formability for profiles, and good paint adhesion

3005 is especially valuable where large formed surfaces are required with a high quality external finish and reliable corrosion behavior. The alloy’s ease of forming and finishing reduces manufacturing cost for architectural panels and appliance bodies while providing better mechanical performance than pure aluminum.

Selection Insights

When selecting 3005, prioritize designs that need better strength than 1000‑series and 3003 while retaining excellent formability and paintability. Choose O or light H‑tempers for deep drawing and H14–H18 for panels where stiffness and yield are more important than maximum elongation.

Compared with commercially pure aluminum (1100), 3005 trades some electrical and thermal conductivity for significantly higher strength and better abrasion resistance. Compared with commonly used work‑hardened alloys such as 3003 or 5052, 3005 typically offers a modest strength increase over 3003 while maintaining comparable formability; it is often preferred where slightly higher strength with good corrosion performance is required. Compared with heat‑treatable alloys like 6061, 3005 offers superior formability and often lower cost, but lower peak strength; use 3005 where forming and surface finish are the limiting factors rather than ultimate tensile strength.

Closing Summary

3005 remains a practical and widely used aluminum alloy because it fills the performance gap between very ductile, commercially pure aluminum and higher‑strength heat‑treatable alloys. Its combination of cold‑work strengthening, good corrosion resistance, excellent surface finish, and predictable fabrication behavior makes it a preferred choice for architectural, automotive, and consumer applications where manufacturability and durability are primary design drivers.