Aluminum 5154: Composition, Properties, Temper Guide & Applications

Comprehensive Overview

5154 is a member of the 5xxx series of aluminum–magnesium alloys, characterized by magnesium as the principal alloying element and by non-heat-treatable strengthening behavior. It sits in the Al–Mg family that balances moderate to high strength with excellent corrosion resistance and good weldability, making it suitable where a combination of formability, strength, and marine durability is required.

Typical major alloying constituents are magnesium (primary), with controlled additions of manganese and traces of chromium, iron, silicon and other elements to control grain structure and work-hardening response. Strength is developed primarily by solid-solution strengthening from magnesium and by strain hardening (cold work); it is not responsive to solution-and-age heat treatment in the way 6xxx or 7xxx series alloys are.

Key traits of 5154 include higher strength than commercially-pure aluminums and many 3xxx alloys, very good resistance to seawater and atmospheric corrosion, excellent weldability using appropriate filler alloys, and good formability in annealed tempers. Typical industries include automotive body and structural components, marine and shipbuilding, pressure vessels and piping, general sheet-metal fabrication and certain aerospace secondary structures.

Engineers choose 5154 over alternatives when the specification calls for a corrosion-resistant, formable material that retains practical strength after welding and modest cold working. It is selected where a non-heat-treatable alloy that avoids post-weld aging cycles and offers consistent plate/sheet performance is advantageous.

Temper Variants

Temper	Strength Level	Elongation	Formability	Weldability	Notes
O	Low	High	Excellent	Excellent	Fully annealed condition for maximum formability
H111	Medium	Moderate	Good	Excellent	Slightly strain-hardened, one-step control of properties
H14	Medium-High	Low-Moderate	Fair	Excellent	Quarter-hard condition from cold working
H16	High	Low	Poor-Moderate	Excellent	Half-hard strain-hardened condition
H32	Medium-High	Moderate	Good	Excellent	Strain-hardened and stabilized by slight thermal treatment
H34 / H36	High	Low	Limited	Excellent	Heavier cold work levels, used where higher strength is required

Tempering of 5154 is achieved by cold work (H tempers) or by annealing (O) rather than by precipitation hardening. The temper chosen sets the balance among strength, ductility and formability; annealed O offers maximum elongation for forming, while H-temper grades deliver higher strength at the cost of decreased bendability.

Temper transitions are commonly controlled by rolling and controlled cooling, or by light thermal stabilization to prevent natural aging effects; weld heat input can locally revert H tempers toward O-level softening in the HAZ, so temper selection must consider downstream welding and fabrication steps.

Chemical Composition

Element	% Range	Notes
Si	≤ 0.40	Deoxidizer and impurity; kept low to preserve ductility
Fe	≤ 0.40	Impurity element; forms intermetallics affecting grain structure
Mn	0.20–0.80	Grain structure control, improves strength and corrosion resistance
Mg	3.1–4.3	Principal strengthening element; provides solid-solution strengthening
Cu	≤ 0.10	Low content to limit loss of corrosion resistance
Zn	≤ 0.25	Minor; controlled to limit strength loss by intermetallic formation
Cr	≤ 0.30	Added in small amounts to control grain growth and recrystallization
Ti	≤ 0.15	Grain refiner; present in trace amounts
Others (each)	≤ 0.05–0.15	Trace elements and residuals; total others limited

Magnesium is the dominant performance driver in 5154: higher Mg increases yield and tensile strengths through solid solution strengthening but increases the risk of magnesium-related sensitization if improperly welded or exposed to certain thermal cycles. Manganese and chromium are used to stabilize the microstructure against recrystallization and to refine grain size; iron and silicon are controlled impurities that influence intermetallic particles and secondary-phase distribution affecting toughness and fatigue.

Mechanical Properties

5154 displays a broad spectrum of tensile behavior depending on temper and thickness, with annealed conditions delivering high ductility and cold-worked tempers showing much higher yield and ultimate strengths. Yield strength in annealed plate is modest, allowing significant forming operations, while H-tempers increase yield by tens of MPa via dislocation accumulation. Elongation in O temper commonly exceeds 20–30% in thin gauge sheet, whereas heavily cold-worked conditions reduce elongation into single-digit percentages.

Hardness correlates with temper and cold work; Vickers or Brinell hardness values rise with H-tempering and with cold reduction. Fatigue performance is influenced by surface finish, thickness, and residual stresses introduced by forming or welding; as with many Al–Mg alloys, properly prepared surfaces and post-weld design reduce stress concentration effects. Thickness effects are notable: thinner gauges typically show higher measured tensile strength for a given temper because of greater cold work and rolling strain imparted during processing.

Property	O/Annealed	Key Temper (H14 / H111)	Notes
Tensile Strength (MPa)	190–240 MPa	250–330 MPa	Values vary with thickness and processing; H-tempers increase UTS
Yield Strength (0.2% offset, MPa)	70–140 MPa	150–260 MPa	H-tempers commonly double or more the annealed yield
Elongation (%)	20–35%	6–18%	Elongation decreases as hardness/strength increases
Hardness (HV)	40–60 HV	70–110 HV	Hardness rises with cold work; measured hardness correlates with yield

Designers should use material supplier certificates and test coupons for precise strength and elongation for the specific temper and thickness in question, since rolling schedules, heat exposure, and post-processing change mechanical data significantly.

Physical Properties

Property	Value	Notes
Density	~2.66 g/cm³	Typical for Al–Mg alloys; used for mass and stiffness calculations
Melting Range	~570–650 °C	Alloy liquidus/seolidus slightly depressed vs pure Al (660 °C)
Thermal Conductivity	~120–150 W/m·K	Lower than pure Al; sufficient for many heat-spreading uses
Electrical Conductivity	~30–45 %IACS	Reduced by alloying; lower than pure Al or low-alloy series
Specific Heat	~900 J/kg·K	Typical for aluminum alloys; useful for thermal transient analysis
Thermal Expansion	~23–24 µm/m·K	Linear coefficient near other Al alloys; relevant for thermal strain

The physical properties of 5154 are typical of medium-strength aluminum alloys: good thermal conductivity and low density make it attractive where weight and thermal performance matter. Electrical and thermal conductivities are reduced relative to commercially pure aluminum by magnesium and other alloying additions, but remain favorable for many structural and heat-sinking applications where conductivity is required alongside mechanical strength.

Designers must account for the alloy’s coefficient of thermal expansion when joining to dissimilar materials; differential expansion and galvanic potential differences can govern fastener selection and insulation requirements in service environments.

Product Forms

Form	Typical Thickness/Size	Strength Behavior	Common Tempers	Notes
Sheet	0.3–6.0 mm	Strength varies with temper and rolling	O, H111, H14	Most common form for body panels, pressure vessels, and general fabrication
Plate	6–150 mm	Lower ductility in thicker sections; tempering by rolling limits	O, H32, H34	Used for structural members and thicker fabricated parts
Extrusion	Wall thickness 1–25 mm, profiles variable	Strength influenced by T4 stabilizing and cold work	H112, H32	Complex sections for structural frames and marine components
Tube	OD 6–200 mm	Behavior depends on drawing and anneal cycles	O, H32	Welded and seamless tubing for fluid systems and structures
Bar/Rod	Ø 3–100 mm	Typically higher as-worked strengths	H14, H16	Used for machined components and fittings

Sheets and thin gauges are the most widely used forms and are produced with controlled rolling schedules to deliver required tempers. Plate and extrusions require different thermal histories and may be more difficult to cold work; heavier sections often require solution annealing or recrystallization control during fabrication.

Choosing a product form must consider manufacturing steps such as drawing, stamping, bending, or welding since each form imposes different initial grain structures and residual stress states that influence final part performance and needed post-processing.

Equivalent Grades

Standard	Grade	Region	Notes
AA	5154	USA	Standard Aluminum Association designation
EN AW	5154	Europe	Commonly quoted as EN AW-5154 in European standards
JIS	A5154	Japan	JIS typically follows similar composition and usage
GB/T	5154	China	Chinese standard designation aligns with international series

Across standards the 5154 designation is often preserved, with minor differences in permitted impurity limits and certification requirements. European and Asian standards may place slightly different limits on trace elements or specify different temper nomenclature and testing protocols, so specifying the standard and temper on procurement documents avoids ambiguity.

Small regional differences can affect applications that are sensitive to intergranular corrosion or require specific mechanical properties; purchasing engineers should request mill certificates and clarify the applicable standard.

Corrosion Resistance

5154 offers very good general atmospheric corrosion resistance and is widely used in marine and coastal environments due to its high magnesium content combined with controlled minor elements. It resists uniform corrosion in seawater and brackish environments better than many heat-treatable alloys and many copper-containing alloys, provided welded zones and fastener interfaces are properly designed and protected.

In chloride-bearing environments, pitting can occur at localized sites such as edges, scratches, or galvanic couples; good surface preparation, coatings and cathodic protection can mitigate pitting. Sensitization (precipitation of β-phase at grain boundaries) is a concern for Al–Mg alloys with higher Mg contents if exposed to temperatures roughly between 65–180 °C for extended times; such sensitization can increase susceptibility to intergranular corrosion, particularly near weld HAZs.

5154 has better resistance to stress-corrosion cracking than many 2xxx and 7xxx alloys, but is not immune: under sustained tensile stress in corrosive chloride environments, SCC risk exists albeit relatively low compared with high-strength heat-treatable alloys. When joining to more noble materials, galvanic corrosion is a design concern; insulating layers and judicious fastener selection reduce potential for accelerated attack.

Fabrication Properties

Weldability

5154 welds readily with common fusion processes such as GTAW (TIG) and GMAW (MIG), and produces sound welds when proper filler metals and pre/post procedures are used. Recommended filler alloys are Al–Mg types such as 5356 or 5183 to match strength and corrosion performance and to minimize hot-cracking; filler selection should consider service requirements and pulsed versus conventional welding regimes. Hot-cracking risk is low relative to some high-strength alloys, but HAZ softening and the potential for sensitization at higher Mg levels require attention to heat input and post-weld protection.

Machinability

Machinability of 5154 is moderate and generally poorer than 6xxx series alloys which are pistol-tempered for easier cutting. Tools of carbide or coated carbide grades with positive rake and strong edge geometry are preferred, and coolant application improves chip evacuation and surface finish. Speeds are typically conservative relative to free‑cutting alloys; feed and depth of cut should be optimized to avoid built-up edge and to control burr formation.

Formability

Formability is excellent in the annealed O temper and remains practical in mild H-tempers; bend radii in O temper can be as tight as 1–2T for many profiles depending on gauge and tooling. Cold-working increases yield and reduces formability, so complex stamping and deep drawing operations prefer O or lightly strain-hardened tempers. Springback is typical for aluminum alloys and must be compensated in tool design, particularly in H-tempers where higher yield increases elastic recovery.

Heat Treatment Behavior

As a 5xxx-series alloy, 5154 is non-heat-treatable; strength is obtained by solid-solution strengthening and by work hardening. There is no beneficial precipitation aging cycle comparable to 6xxx alloys. Thermal treatments are therefore focused on annealing and stabilizing rather than solution/aging sequences.

Full annealing (O) restores ductility by allowing recrystallization and can be accomplished at temperatures in the range commonly used for Al–Mg alloys (typically 350–420 °C for appropriate times), followed by controlled cooling. Cold work is used to obtain H tempers; stabilization treatments (light heating) can be used to minimize natural aging effects and to set a desired temper. Welded structures may be heat-treated only to anneal or stress-relieve; such operations will reduce strength achieved by prior cold work.

High-Temperature Performance

5154 retains usable mechanical properties at moderately elevated temperatures, but strength declines with increasing temperature as solid-solution strengthening becomes less effective and dislocation motion increases. Continuous service temperatures are typically recommended below about 100–150 °C to avoid noticeable strength loss and to prevent potential sensitization effects if exposed to certain temperature/time windows.

Oxidation is minimal due to the protective aluminum oxide film, and there is no rapid high-temperature scaling typical of ferrous alloys. However, exposure to thermal cycles and welding can create localized HAZ regions with softened properties and altered corrosion performance. For elevated-temperature load-bearing applications, designers commonly select heat-resistant alloys or derate allowable stresses for 5154.

Applications

Industry	Example Component	Why 5154 Is Used
Automotive	Body panels, inner structural components	Good formability, corrosion resistance, acceptable strength for non-primary structural parts
Marine	Hull panels, superstructure, piping	Excellent resistance to seawater corrosion and weldability for shipboard fabrication
Aerospace	Secondary fittings, fairings	High strength-to-weight for non-primary structures and good fabrication characteristics
Electronics	Enclosures, thermal spreaders	Low density and decent thermal conductivity for lightweight housings
Pressure Vessels / Tanks	Tanking, LPG components	Corrosion resistance and weldability combined with adequate strength in formed geometries

5154 is chosen in these applications where a balanced set of mechanical properties, corrosion resistance and fabrication flexibility reduces life-cycle costs and simplifies manufacturing. Its non-heat-treatable nature simplifies processing while still providing higher strength than many low-alloyed alternatives.

Selection Insights

5154 is a pragmatic choice when needing a corrosion-resistant aluminum with better strength than commercially pure aluminum while retaining good formability and weldability. Compared with 1100 (commercially pure), 5154 trades some electrical and thermal conductivity and ultimate formability for substantially higher yield and tensile strength, making it preferable for structural sheet and marine parts.

Against common work‑hardened alloys like 3003 or 5052, 5154 generally offers higher strength while maintaining similar or slightly improved corrosion resistance; choose 5154 when the design requires that additional strength while staying within the Al–Mg family. Compared to heat‑treatable alloys such as 6061 or 6063, 5154 provides better post-weld corrosion behavior and avoids heat‑treatment complexity; select 5154 when welding and consistent corrosion resistance trump the higher peak strengths available from heat‑treatable alloys.

For procurement, balance cost and availability with temper and thickness requirements, and verify mill certificates for Mg content and mechanical property tests where fatigue, welding or marine exposure are critical design drivers.

Closing Summary

5154 remains a widely used Al–Mg alloy because it uniquely combines solid-solution-strengthened mechanical performance with excellent corrosion resistance and fabrication versatility; its ease of welding, good formability in annealed form, and reliable behavior across many product forms keep it relevant for automotive, marine and general structural engineering applications.