Aluminum A5052: Composition, Properties, Temper Guide & Applications

Comprehensive Overview

A5052 is a 5xxx-series wrought aluminum–magnesium alloy, categorized in the Al–Mg family where magnesium is the principal alloying element. The alloying philosophy centers on Mg additions in the ~2.2–2.8 wt% range with small controlled additions of Cr and Mn to control grain structure and limit recrystallisation during fabrication.

A5052 is a non-heat-treatable alloy whose primary strengthening mechanism is solid-solution strengthening combined with cold work (strain hardening) and microalloying stabilization. This produces a combination of moderate strength, excellent corrosion resistance—especially in marine environments—good weldability, and favorable formability in soft tempers.

Key traits that define A5052 are its elevated yield and ultimate strengths relative to commercially pure Al (1xxx series), its superior resistance to seawater and chloride-containing environments compared with many other Al alloys, and its reasonable fatigue performance. Typical industries using A5052 include marine construction, transportation (truck fuel tanks and body panels), consumer appliances, HVAC ductwork, and certain aerospace secondary structures. The alloy is often chosen where a balance of formability, moderate strength, and corrosion resistance is required without the need for precipitation hardening.

A5052 is selected over 1xxx and 3xxx alloys when a higher strength and better corrosion resistance are needed without sacrificing much formability. It is preferred over many heat-treatable 6xxx/7xxx alloys where welding and in-service corrosion (especially saltwater) are critical constraints and when the cost and processing of heat treatment are undesirable.

Temper Variants

Temper	Strength Level	Elongation	Formability	Weldability	Notes
O	Low	High	Excellent	Excellent	Fully annealed; maximum ductility for forming.
H111	Low–Moderate	High	Very good	Very good	General-purpose strain-aged temper with modest, non-directional work hardening.
H14	Moderate	Moderate–High	Good	Very good	Strain-hardened to a quarter hard condition; common for formed components.
H16	Moderate–High	Moderate	Fair–Good	Very good	Half-hard condition with improved strength at expense of formability.
H32	High	Moderate	Good (with care)	Good	Strain-hardened and stabilized; widely used for sheet and plate in marine applications.
H34	High	Low–Moderate	Limited	Good	Strain-hardened to a higher level than H32; used where higher strength is required.
H38	Higher	Low	Limited	Good	Commercially available higher-strength strain-hardened condition for thicker products.

The temper designation for A5052 directly controls its tensile and yield strengths through the degree of cold work and any stabilizing treatments. Soft tempers (O, H111) maximize formability and elongation and are chosen for deep drawing and complex shaping operations, whereas H3x tempers deliver significantly higher yield strength at the cost of reduced elongation and increased springback during forming.

Weldability is generally excellent across tempers because A5052 does not rely on precipitate strengthening; however, localized softening or recovery in the heat-affected zone (HAZ) can reduce strength of cold-worked tempers near welds. Designers must account for temper-specific springback and bend radius during forming and may anneal after forming if maximum ductility is required.

Chemical Composition

Element	% Range	Notes
Si	≤ 0.25	Impurity; controlled to limit intermetallics.
Fe	≤ 0.40	Impurity; higher Fe can reduce ductility and increase intermetallic inclusions.
Mn	0.10–0.50	Grain structure control; helps strength and reduces susceptibility to recrystallization.
Mg	2.2–2.8	Primary alloying element; provides solid-solution strengthening and improved corrosion resistance.
Cu	≤ 0.10	Kept low to preserve corrosion resistance; higher Cu reduces pitting resistance.
Zn	≤ 0.10	Minor; generally treated as impurity.
Cr	0.15–0.35	Controls grain structure and helps stabilize cold-worked tempers against recrystallization.
Ti	≤ 0.15	Deoxidizer and grain refiner in castings; minor in wrought alloys.
Others	≤ 0.05 (each) / ≤ 0.15 (total)	Trace elements with limits; verify mill certs for specific limits.

Magnesium is the performance driver for A5052: it increases yield and tensile strength via solid solution strengthening while maintaining good ductility in softer tempers. Chromium is intentionally added in controlled amounts to retard recrystallization and preserve the work-hardened microstructure during elevated temperature exposures and fabrication. Low Cu and Zn contents preserve the alloy’s strong resistance to pitting and crevice corrosion in chloride environments.

Mechanical Properties

A5052 exhibits tensile behavior characteristic of a work-hardened Al–Mg alloy: soft tempers show low yield strength but high elongation, while H3x tempers show substantially higher yield and ultimate strength with reduced ductility. Yield strength is sensitive to cold work and thickness; thin sheet cold-rolled to H32 can reach yields approaching structural alloy levels, while thicker plate or annealed sections will be considerably lower. Hardness follows the same trend as strength and is commonly used as a quick shop-floor proxy for temper verification.

Fatigue performance of A5052 is generally good for Al–Mg alloys; the alloy benefits from the absence of fatigue-retarding precipitates that can act as crack nucleation sites. Surface condition, forming-induced residual stresses, and welds are primary drivers of fatigue life, so proper surface finishing and weld procedure qualification are important for cyclic applications. Thickness affects both work-hardening achievable and constraint to plastic deformation; thinner gauges can be strengthened more by cold rolling, while thicker sections require more drastic cold work to reach comparable properties.

Practical property ranges (typical values; verify mill certificates for project-specific use) are summarized below.

Property	O/Annealed	Key Temper (e.g., H32)	Notes
Tensile Strength (UTS)	110–150 MPa	215–260 MPa	UTS depends strongly on temper and thickness; H3x roughly doubles strength vs O.
Yield Strength (0.2% offset)	35–70 MPa	140–200 MPa	H32 yield often ~140–200 MPa depending on product form and temper.
Elongation (in 50 mm)	15–25%	6–12%	Elongation drops with increased cold work; formability still acceptable in many H-tempers.
Hardness (HB)	25–40	55–70	Hardness ranges given are typical Brinell numbers; Vickers/Rockwell will differ.

Physical Properties

Property	Value	Notes
Density	2.68 g/cm³ (168 lb/ft³)	Typical for wrought aluminium–magnesium alloys; useful for mass calculations.
Melting Range	~605–650 °C	Solidus–liquidus range depends on exact composition and impurities.
Thermal Conductivity	~138 W/m·K (at 20 °C)	Lower than pure Al due to alloying; still good for heat spreading applications.
Electrical Conductivity	~29–36 %IACS	Conductivity reduced by Mg and other solutes; thicker sections and tempers vary slightly.
Specific Heat	~900 J/kg·K	Typical for aluminium alloys; used for thermal mass and transient calculations.
Thermal Expansion	23.5–24.8 ×10⁻⁶ /K	Linear thermal expansion similar to other Al alloys; important when mating with dissimilar materials.

The physical properties make A5052 suitable for applications that require a combination of light weight, reasonable thermal conduction, and stable dimensional behavior with temperature. Electrical conductivity is reduced relative to pure aluminium due to alloying but remains adequate for many electrical enclosures and shielding uses; use lower-alloyed 1xxx series if maximum conductivity is required.

Thermal design should account for the alloy’s moderate conductivity and relatively high coefficient of thermal expansion when interfacing with steels or composites to avoid excessive thermal strain in service, especially in cyclic thermal environments.

Product Forms

Form	Typical Thickness/Size	Strength Behavior	Common Tempers	Notes
Sheet	0.3 mm – 6 mm	Strength increases with cold rolling	O, H111, H14, H32	Widely used for cladding, panels, and marine hulls.
Plate	6 mm – 50 mm	Less cold work achievable; lower strain-hardening	O, H32, H34, H38	Plate used for structural and welded components; thicker plate often supplied in H3x tempers.
Extrusion	Profiles up to several meters	Properties influenced by extrusion ratio and subsequent work	O, H111, H32	Extruded sections used for frames, rails, and structural profiles.
Tube	OD 6 mm – 200 mm	Wall thickness affects attainable strength	O, H14, H32	Welded and seamless tubes for fuel tanks, HVAC, and marine tubing.
Bar/Rod	Diameters up to ~100 mm	Machinability and cold work dependent	O, H14, H16	Solid bars for machined fittings and turned components.

Sheet and plate manufacture routes (cold rolling, stretch leveling) alter dislocation densities and texture, directly affecting yield and elongation. Extrusions and tubes are often produced in softer tempers to facilitate deformation and may be subsequently cold worked to increase strength.

Choice of product form is driven by fabrication needs: thin sheet for forming and drawing, plate for welded structural parts, extrusions for complex cross-sections, and tube/bar for fabricated assemblies and machined parts. Post-production cold work or annealing steps can be applied to tailor mechanical performance for the intended manufacturing route.

Equivalent Grades

Standard	Grade	Region	Notes
AA	A5052	USA	Aluminum Association designation; widely referenced in mill datasheets.
UNS	A95052	International	Unified Numbering System designation for A5052.
EN AW	EN AW-5251 / EN AW-5052 (verify)	Europe	European designations vary by manufacturer; exact match should be confirmed against chemistry.
JIS	A5052	Japan	Japanese standard often uses the same numeric alloy designation for 5xxx alloys.
GB/T	AlMg2.5	China	Chinese designation corresponds to an Al–Mg alloy with similar magnesium content; verify chemical spec.

Equivalency across standards is approximate because manufacturing practices, impurity limits, and permitted trace elements can vary by region and mill. Engineers should always cross-reference the exact chemical composition and mechanical property limits on supplier mill certificates before qualifying material for a critical application.

Corrosion Resistance

A5052 offers very good atmospheric corrosion resistance and is notably robust in marine and chloride-laden environments owing to its magnesium content and low copper. The alloy forms a protective oxide that, in many service conditions, provides long-term protection against pitting and general corrosion; this behavior is superior to many heat-treatable alloys that contain higher Cu or Zn. Protective coatings and anodizing can further enhance performance where aesthetic or additional barrier protection is required.

In seawater and splash-zone exposures A5052 typically outperforms 6xxx and 2xxx series alloys in terms of pitting resistance, which is why it is widely used for marine hulls, fuel tanks, and deck hardware. A5052 is susceptible to localized corrosion if galvanically coupled to more noble metals (e.g., copper alloys or stainless steels) without proper isolation; therefore fastener selection and electrical isolation are important in mixed-metal assemblies.

Stress corrosion cracking (SCC) susceptibility for A5052 is low compared with high-strength heat-treatable alloys, but exposure to tensile stresses combined with corrosive chloride environments can still cause crack initiation in highly stressed components. Designers should avoid introducing tensile residual stresses in critical areas, ensure good drainage, and consider cathodic protection or appropriate fastener materials when long-term immersion is expected.

Fabrication Properties

Weldability

A5052 is readily weldable by common fusion methods such as TIG (GTAW) and MIG (GMAW) and also performs well with resistance and spot welding in sheet forms. Filler alloys such as ER5356 or ER5183 are commonly recommended for butt and fillet welds to provide compatible corrosion performance and to limit hot cracking risk; ER5356 provides a favorable balance of strength and ductility. Hot cracking risk is low relative to many 2xxx and 7xxx alloys, however localized HAZ softening can reduce strength in cold-worked tempers, and post-weld mechanical properties should be verified when welds are in high-stress regions.

Machinability

Machinability of A5052 is moderate and generally better than many Al–Si casting alloys but worse than free-cutting 2xxx alloys. The alloy machines well with high-speed steel or carbide tooling and benefits from rigid setups, positive rake tooling, and appropriate chip break geometries to avoid long, continuous ribbons. Typical practice uses high spindle speeds, moderate feeds, and cutting fluids designed for aluminum to control built-up edge and improve surface finish; expect good surface finishes but moderate tool wear due to work-hardening tendencies in thin sections.

Formability

Formability of A5052 in soft tempers is excellent and suitable for deep drawing, hemming, and complex stampings; minimum bend radii depend on temper and thickness but are generally in the range of 1–3T (T = thickness) for softer tempers. Cold working increases strength and springback, so H32/H34 components require compensated tooling and often stress-relief or partial anneal after forming to meet dimensional tolerances. Warm forming can extend formability limits but is seldom required for typical 5052 applications; designers should perform forming trials for complex geometries.

Heat Treatment Behavior

A5052 is a non-heat-treatable alloy; it does not respond to solution treatment and aging to produce precipitation hardening as 6xxx or 7xxx alloys do. Strength increases are achieved primarily via cold working (strain hardening) and by stabilizing additions such as chromium that reduce recovery during elevated-temperature exposure.

Annealing (softening) is achieved by heating to the appropriate temperature (commonly ~300–415 °C for partial/full anneal, depending on section size and source recommendations) to reduce dislocation density and restore ductility. Stabilized tempers (H3x) can be produced by controlled heating to relieve residual stresses while preserving a portion of the cold work; post-forming thermal treatments are commonly used to tailor mechanical properties and springback.

High-Temperature Performance

A5052 exhibits progressive strength reduction with increasing temperature; above approximately 100–150 °C the yield strength begins to decrease significantly, and at elevated service temperatures (e.g., >250 °C) the alloy loses much of its room-temperature strength. For continuous service, keeping operating temperatures below ~100 °C is advisable for components relying on standard cold-worked strengths.

Oxidation at elevated temperatures is minimal relative to ferrous alloys because aluminum rapidly forms a protective oxide, but prolonged high-temperature exposure can promote recovery and annealing of the work-hardened microstructure, leading to softening. The HAZ produced during welding and thermal cycles can see localized recovery and strength loss; engineers should specify appropriate temper margins or design reinforcements to mitigate HAZ-related performance degradation.

Applications

Industry	Example Component	Why A5052 Is Used
Automotive	Fuel system components, body panels for commercial vehicles	Good forming, corrosion resistance, weldability for fuel and exterior parts.
Marine	Hull panels, deck hardware, fittings	Excellent seawater corrosion resistance and good strength-to-weight.
Aerospace	Secondary structure, brackets, fairings	Lightweight, corrosion resistant, and readily formed and welded.
Electronics	Enclosures and heat spreaders	Adequate thermal conductivity and formability for EMI/thermal components.
HVAC / Construction	Ducting, roofing, cladding	Weather resistance, ease of fabrication, and availability in sheet/coil.

A5052’s combination of fabrication friendliness, corrosion resistance, and moderate mechanical properties makes it a go-to alloy for components where service environment and manufacturability outweigh the need for the highest possible strength. The alloy’s broad product availability in sheet, plate, and extruded forms helps keep production and procurement straightforward.

Selection Insights

A5052 is an excellent selection when engineers need higher strength than commercially pure aluminum (1100) while retaining good formability and corrosion resistance. Compared with 1100, A5052 trades some electrical conductivity and even somewhat diminished deep-drawability for substantially improved mechanical strength and service robustness.

When compared with 3003 and other Mn-bearing, work-hardened alloys, A5052 typically offers higher strength and superior pitting resistance in chloride environments due to its higher Mg content. Against heat-treatable alloys