Aluminum 5454: Composition, Properties, Temper Guide & Applications

Comprehensive Overview

5454 is a member of the 5xxx (Al-Mg) series of wrought aluminum alloys, characterized by magnesium as the principal alloying element. It is often specified as AlMg3 in European nomenclature and occupies the mid-strength range of the magnesium alloys, balancing mechanical performance with excellent corrosion resistance.

The major alloying elements are magnesium and controlled additions of manganese to improve strength and grain structure. 5454 is a non-heat-treatable alloy; its strengthening is achieved primarily through solid-solution strengthening from magnesium and by strain hardening during cold work rather than by precipitation heat treatments.

Key traits of 5454 include good tensile strength for a non-heat-treatable alloy, strong resistance to marine and atmospheric corrosion, very good weldability by common fusion processes, and good formability in annealed or lightly-worked tempers. Typical industries that use 5454 include marine, transportation, pressure vessels, and general structural fabrications where corrosion resistance and moderate strength are required.

Engineers select 5454 over other alloys when they need a combination of better strength than commercially pure aluminum and better corrosion resistance than some higher-strength alloys. It is often chosen where weldability, post-weld performance, and in-service durability in chloride environments are more important than achieving the absolute highest strength-to-weight available from heat-treatable alloys.

Temper Variants

Temper	Strength Level	Elongation	Formability	Weldability	Notes
O	Low	High (20–35%)	Excellent	Excellent	Fully annealed condition for maximum ductility
H111 / H112	Low–Moderate	High–Moderate	Very Good	Excellent	Slightly strain-hardened or worked; commonly supplied for easy forming
H14	Moderate	Moderate (8–15%)	Good	Excellent	Quarter-hard, common for sheet applications with improved strength
H16	Moderate–High	Reduced	Fair–Good	Excellent	Half-hard, trade-off more strength for some loss in ductility
H18	High	Low	Limited	Excellent	Full-hard, used where higher strength and stiffness are required
H24	Moderate	Moderate	Good	Excellent	Strain-hardened and partially annealed; balance of formability and strength
T5 / T6 / T651	Not typical	Not typical	Not typical	Not typical	Temper designations for heat-treatable alloys; generally not applicable to 5454

Temper has a direct and predictable influence on 5454 properties because it is non-heat-treatable. Annealed (O) tempers maximize ductility and corrosion resistance, making them the best choice for deep drawing and severe cold forming operations.

As strain-hardening increases (H14 through H18) tensile and yield strengths rise while elongation and bend performance decline. Because 5454 does not respond to solution + aging sequences, temper control is achieved by mechanical processing and controlled anneals rather than precipitation treatments.

Chemical Composition

Element	% Range	Notes
Si	≤ 0.30	Impurity; kept low to preserve corrosion performance and ductility
Fe	≤ 0.40	Intermetallic former; controlled to limit degradation of toughness
Mn	0.40–1.20	Improves strength and grain structure; helps control recrystallization
Mg	2.6–3.6	Principal strengthening element; provides solid-solution strengthening and corrosion resistance
Cu	≤ 0.10	Kept low to avoid reduced corrosion resistance and galvanic effects
Zn	≤ 0.20	Minor; excessive Zn can reduce corrosion resistance
Cr	≤ 0.25	Added in small amounts in some variants to control grain structure and recrystallization
Ti	≤ 0.15	Grain refiner in cast variants; minor effect in wrought products
Others	≤ 0.15 each, ≤ 0.35 total	Residuals and trace additions; controlled to maintain alloy properties

The relatively high magnesium content (around 3 wt%) is the dominant factor in 5454’s mechanical and corrosion behavior. Manganese additions are purposeful and moderate; they help offset grain boundary weakening and contribute to strength without undermining corrosion resistance. Low copper and silicon ensure that the naturally forming oxide film remains protective in marine and industrial atmospheres.

Mechanical Properties

5454 exhibits a tensile/yield profile characteristic of mid-strength 5xxx series alloys, with significant ductility in annealed tempers and progressive strength gains with strain hardening. Yield strength increases substantially between O and half/full-hard tempers while tensile strength also rises but typically with a sharper reduction in elongation. The alloy shows good toughness and energy absorption compared with many higher-strength, heat-treatable aluminum alloys.

Fatigue performance is reasonable in chloride-free environments but is sensitive to surface condition, welds, and stress concentrators. Welded joints commonly show HAZ softening relative to strain-hardened base metal; design should account for local reductions in yield and fatigue limit. Thickness and product form influence mechanical values—thicker plate often shows slightly lower measurable yield due to microstructural heterogeneity and potential for residual stresses.

Hardness increments track with strain-hardening; the annealed alloy has low Brinell/Vickers values while H16–H18 tempers reach substantially higher hardness numbers. Correlation between hardness and tensile strength is robust enough for rapid shop-floor checks, but full tensile testing is recommended for critical components and welded assemblies.

Property	O/Annealed	Key Temper (e.g., H16/H18)	Notes
Tensile Strength (UTS)	~95–150 MPa	~200–310 MPa	Wide range depending on temper and product form; sheet vs plate differences
Yield Strength (0.2% offset)	~30–70 MPa	~120–240 MPa	HAZ welding softening can reduce local yield strength in welded assemblies
Elongation (A50 or A5)	~20–35%	~4–15%	Annealed yields highest ductility; full-hard has limited elongation
Hardness (HB)	~25–45 HB	~60–110 HB	Hardness correlates with cold work level and is useful for process control

Physical Properties

Property	Value	Notes
Density	2.66–2.70 g/cm³	Typical for wrought Al-Mg alloys, used in mass and stiffness calculations
Melting Range	~590–645 °C	Solidus and liquidus vary with exact composition and impurities
Thermal Conductivity	~120–150 W/m·K	Lower than pure Al but still high; important for heat-sinking and thermal design
Electrical Conductivity	~32–38 %IACS	Reduced relative to pure aluminum due to alloying additions
Specific Heat	~880–910 J/kg·K	Useful for thermal transient and heat capacity calculations
Thermal Expansion	~23–24 µm/m·K (20–100 °C)	Typical coefficient of thermal expansion for aluminum alloys

The density and thermal properties make 5454 attractive for structures where mass and heat dissipation matter, such as marine hulls and heat exchanger headers. Its thermal conductivity remains high enough for many thermal management tasks, although not as high as pure aluminum or some 6xxx alloys with different microstructures.

Electrical conductivity is moderate; 5454 is not chosen for conductors where high IACS is required, but it can be used where combined mechanical/corrosion performance and adequacy of conductivity are needed. Thermal expansion considerations are standard for aluminum design and must be accounted for in mixed-material structures.

Product Forms

Form	Typical Thickness/Size	Strength Behavior	Common Tempers	Notes
Sheet	0.3–6 mm	Uniform; sensitive to rolling direction	O, H111, H14, H16	Widely used for panels, enclosures, and marine sheathing
Plate	6–150 mm	Slightly lower measured yield in thicker sections	O, H111	Used for structural components and pressure-containing parts
Extrusion	Profiles up to large section	Strength varies with section and cooling	O, H111, H14	Good for structural frames and rails; requires process control for Mg distribution
Tube	Diameters up to several hundred mm	Good axial and hoop strength when cold-worked	O, H16, H18	Common for marine and transport piping and structural tubing
Bar/Rod	Various diameters	High uniformity in cross-section	H14–H18	Used for machined fittings, fasteners and fabricated parts

Processing route and product form change mechanical behavior and achievable tempers. Sheets rolled thin to medium thickness respond predictably to strain-hardening and annealing operations, while thicker plates need more aggressive rolling and controlled cooling to achieve uniform properties.

Extrusions and tubes require attention to homogenization and internal porosity control because Mg-rich alloys can exhibit segregation in thick sections. Selection of temper at the product stage is fundamental to matching forming operations and final service requirements.

Equivalent Grades

Standard	Grade	Region	Notes
AA	5454	USA	Aluminum Association designation often used in North American specs
EN AW	5454	Europe	Common European designation (AlMg3); standardized in EN 573/754 for wrought products
JIS	A5454	Japan	Japanese Industrial Standard variant with similar Mg content and mechanical requirements
GB/T	5454	China	Chinese standard grade aligned with international chemical and mechanical ranges

Equivalency across standards is generally close but not identical; permissible impurity limits and specified mechanical property test methods can vary. Engineers should cross-check mill certificates and national standards for thickness-dependent property limits, tempers, and permitted processing routes before finalizing material acceptance criteria.

Corrosion Resistance

5454 has strong atmospheric corrosion resistance and is particularly well suited to marine environments because the magnesium-rich matrix forms a tenacious, self-healing oxide/hydroxide film. In stagnant chloride-rich conditions, localized pitting can occur if surface films are damaged or if aggressive galvanic coupling exists, but 5454 performs better than many copper-containing alloys in such environments.

Stress corrosion cracking (SCC) susceptibility in 5454 is low compared with higher-strength aluminum alloys, but SCC risk can increase under tensile stress in warm chloride environments combined with weld-induced residual stresses. Design practices recommend avoiding tensile overstress, controlling weld residuals, and using post-weld treatments or cathodic protection in severe service.

Galvanic interactions should be managed when 5454 is paired with metals more noble than aluminum (e.g., stainless steel, copper), particularly in marine exposures. Using compatible fasteners, isolating layers, or sacrificial anodes reduces galvanic attack and extends service life relative to uncontrolled material pairings.

Fabrication Properties

Weldability

5454 welds readily with common fusion methods such as MIG (GMAW) and TIG (GTAW). Recommended filler alloys are typically ER5356 or ER5183 for higher strength or corrosion-resistant welds, chosen to match base alloy chemistry and to control porosity and ductility. Hot-cracking risk is low relative to some 2xxx and 7xxx series alloys, but HAZ softening and loss of strain-hardening are common; welded structures should be designed to tolerate HAZ reductions in local yield.

Machinability

Machinability of 5454 is moderate to fair relative to free-machining or aluminum-silicon casting alloys; it machines better than many high-strength wrought alloys but less readily than pure aluminum. Use sharp carbide or high-speed steel tooling, moderate to high feeds, and lower cutting speeds with good coolant/lubrication to manage continuous chips and to avoid built-up edge. Surface finish and dimensional accuracy are generally good if tooling and speeds are optimized for aluminum alloys.

Formability

Formability is excellent in the annealed condition and remains good in lightly-worked tempers; deep drawing and complex stamping operations favor O or H111 tempers. Minimum bend radii depend on temper and thickness; typical shop practice uses inside radii of 2–3 times thickness for H14/H16 and down to 1–2 times thickness in fully annealed sheet. Cold working increases yield and tensile but reduces elongation and can introduce springback, which must be accounted for in die design.

Heat Treatment Behavior

5454 is a non-heat-treatable alloy and does not respond to conventional solution heat-treat + aging cycles used for 6xxx or 7xxx series alloys. Attempts to solution treat and age will not produce the precipitation-hardening strengthening mechanisms that are effective in those heat-treatable families.

Mechanical properties are controlled by work hardening and by thermal processes such as annealing. Full annealing temperatures for wrought 5xxx alloys are typically in the range of 300–415 °C depending on product form and section thickness; controlled furnace anneals and subsequent quenching or slow cooling are used to restore ductility and soften the material.

Intermediate or partial anneals (e.g., to produce H24 or stabilized tempers) are used to achieve particular balances of strength and formability. Stabilization or low-temperature stress-relief cycles can reduce residual stresses without significantly altering the alloy’s strength.

High-Temperature Performance

Strength of 5454 decreases with increasing temperature and is modestly reduced even at moderately elevated service temperatures (above ~100 °C). Long-term exposure to temperatures approaching 150–200 °C will further degrade mechanical properties through recovery and microstructural changes, so continuous service temperatures are generally limited to well below those values.

High-temperature oxidation is not a severe concern for aluminum alloys because of the protective oxide layer, but elevated temperatures accelerate oxide growth and can affect surface finishing and coatings. Welded zones and heat-affected regions can show enhanced softening under elevated temperature exposure; design should consider creep and relaxation if sustained loads and temperatures are involved.

Applications

Industry	Example Component	Why 5454 Is Used
Automotive	Fuel lines, non-structural body panels	Good formability, weldability and corrosion resistance
Marine	Hull plating, superstructure panels	Excellent marine corrosion resistance and strength-to-weight
Aerospace	Secondary structures, access panels	Corrosion resistance and reasonable strength for non-primary structures
Electronics	Enclosures, heat spreaders	Adequate thermal conductivity with corrosion durability
Pressure Vessels / Tanks	Storage tanks, piping	Good weldability and resistance to seawater and industrial atmospheres

5454’s combination of weldability, corrosion resistance, and mid-range strength make it a versatile choice across multiple industries. It is especially favored for components exposed to corrosive atmospheres where the cost and weight advantages of aluminum are needed without sacrificing in-service durability.

Selection Insights

Choose 5454 when you need an alloy that balances corrosion resistance, weldability, and moderate strength without relying on heat-treatment. It is particularly suited to marine, transportation, and general structural applications where post-weld performance and resistance to chloride environments are priorities.

Compared with commercially pure aluminum (e.g., 1100), 5454 offers substantially higher tensile and yield strength at the cost of modestly reduced electrical and thermal conductivity. Compared with common work-hardened alloys such as 3003 or 5052, 5454 usually provides higher strength and equivalent or better marine corrosion resistance, making it preferable for hull and structural plate uses.

Compared with heat-treatable alloys such as 6061 or 6063, 5454 will not achieve the same peak strength but is often chosen when superior corrosion resistance, simpler fabrication (welding without post-heat-treatment), and better ductility in certain tempers are more important than maximum strength.

Closing Summary

5454 remains a relevant and widely used alloy because it delivers a robust combination of corrosion resistance, weldability, and mid-level mechanical performance without the complexity of heat treatment. Its suitability for marine and corrosive environments, together with predictable fabrication behavior across sheet, plate and extruded forms, keeps it a practical choice for designers and fabricators seeking durable, cost-effective aluminum solutions.