Aluminum 8079: Composition, Properties, Temper Guide & Applications

Comprehensive Overview

Alloy 8079 is part of the aluminum 8xxx series, a family of low-alloy and specialty aluminum grades often developed for packaging, electrical and foil applications. It is categorized among low-strength, high-formability alloys with chemistry tailored for consistent rolling and surface quality rather than for peak structural strength.

Major alloying elements in 8079 are low-level additions of iron and silicon with trace manganese, magnesium and other residuals; the matrix is essentially industrial-purity aluminum. Strengthening is achieved primarily through solid-solution effects and cold work (strain hardening), not by classical precipitation hardening used in 2xxx or 6xxx series alloys.

Key traits of 8079 include excellent formability, good surface finish, acceptable corrosion resistance in atmospheric environments, and high electrical and thermal conductivity compared with higher-alloyed structural grades. Weldability is generally good for gas-shielded fusion processes when suitable filler materials are used, and susceptibility to hot cracking is low due to the low alloy content.

Typical industries include packaging (foil and laminated products), flexible and rigid packaging converters, electrical conductors and some lightweight structural applications where forming and surface quality are critical. Engineers choose 8079 where a balance of ductility, surface quality, and conductivity is required and where higher-strength, heat-treatable alloys are unnecessary or would complicate processing.

Temper Variants

Temper	Strength Level	Elongation	Formability	Weldability	Notes
O	Low	High	Excellent	Excellent	Fully annealed, maximum ductility for deep drawing and foil processes
H12	Low-Medium	Moderate	Very Good	Very Good	Slight strain hardening, retains good formability and dimensional stability
H14	Medium	Moderate	Good	Very Good	Commercial temper for moderate-strength sheet with good drawability
H18	Medium-High	Lower	Fair	Good	Higher work hardening for applications needing springback/rigidity
T4 (if used)	Low-Medium	High	Very Good	Very Good	Solution treated and naturally aged; rarely applied to low-alloy 8xxx grades
T5 (rare)	Medium	Moderate	Good	Good	Artificially aged after cooling from hot working where applicable
T6 (rare)	Medium-High	Lower	Limited	Good	Artificially aged to higher strength in modified chemistries; uncommon for standard 8079

Temper selection has a direct and predictable impact on the engineering properties of 8079. O temper maximizes ductility and formability for deep drawing and foil production, while H‑tempers provide progressively higher yield and strength at the expense of elongation and formability.

H‑tempers (H12–H18) are the most commonly used in sheet and strip because they offer a compromise between springback control and formability for presswork; T‑tempers are rare and only apply when proprietary modified chemistries or supplier-specific processing allow limited precipitation effects.

Chemical Composition

Element	% Range	Notes
Si	0.10–0.60	Controls fluidity during casting and can form dispersoids that affect rolling behavior
Fe	0.20–1.00	Common impurity, influences strength and grain structure; higher Fe lowers ductility slightly
Mn	0.02–0.30	Small additions refine grain and improve strength without large loss of formability
Mg	0.01–0.20	Typically low; increases strength slightly but kept low to preserve corrosion resistance
Cu	0.01–0.20	Usually minimized; small amounts can raise strength but reduce corrosion resistance
Zn	0.01–0.25	Kept low to avoid forming high-strength phases that impair formability
Cr	0.00–0.10	Trace levels may be present to control recrystallization in some producer variants
Ti	0.00–0.10	Often used as a grain refiner when control of as-cast grain is required
Others (including residuals)	Balance to 100 (Al)	Includes Al remainder and trace elements; exact spec varies by supplier and product form

The chemistry of 8079 is intentionally restrained to maintain high ductility, surface quality and conductivity while offering modest strength gains over pure aluminum. Silicon and iron are the principal alloying/residual elements; they influence rolling stability, mechanical scattering, and grain structure.

Minor additions of manganese, magnesium or controlled impurities are used by manufacturers to tune recrystallization behavior, reduce edge cracking during rolling, and set the response to cold work while keeping corrosion behaviour favorable.

Mechanical Properties

Tensile behavior of 8079 is typical of low-alloy, non-heat‑treatable aluminum: a low-to-moderate ultimate tensile strength with considerable uniform and total elongation in annealed and light-hardened conditions. Yield strength scales with temper and thickness; thin-gauge, cold-rolled H‑tempers show higher yield and earlier onset of plastic flow compared with thick, annealed product. Fatigue performance is adequate for non-critical cyclic loading but is limited compared with high-strength alloys due to lower yield and endurance limits.

Elongation is high in O‑tempers (suitable for deep drawing and complex forming) and decreases progressively with increasing H‑number. Hardness tracks strength and cold work; soft annealed material exhibits low hardness and easy formability while H‑tempers show modest increments in Brinell or Vickers values. Thickness influences both strength and ductility, with thinner gauges typically showing higher apparent strength after rolling due to work hardening and grain size effects.

Fracture modes are ductile for typical forming strains, but care must be taken with sharp notches and radii where local work hardening can initiate microvoid coalescence at lower global strains. Surface defects, inclusions and edge condition substantially influence tensile scatter and should be assessed in quality control for critical forming operations.

Property	O/Annealed	Key Temper (e.g., H14/T6)	Notes
Tensile Strength (UTS)	70–120 MPa	120–210 MPa	Wide ranges depend on thickness, producer processing and exact temper
Yield Strength (0.2% offset)	30–50 MPa	70–160 MPa	H‑tempers roughly double or more the annealed yield in common sheet gauges
Elongation (A50 mm)	25–40%	8–20%	Formability requirement drives temper selection; annealed gives max elongation
Hardness (HB/Vickers)	20–35 HB	35–70 HB	Hardness increases with degree of cold work; values approximate for comparison

Physical Properties

Property	Value	Notes
Density	2.70 g/cm³	Typical for commercial aluminum alloys; used for mass and stiffness calculations
Melting Range	643–658 °C	Practical casting/processing limits; solidus/liquidus vary slightly with impurities
Thermal Conductivity	160–220 W/m·K	High compared with many alloys; depends on purity and cold work
Electrical Conductivity	45–60 % IACS	Lower than pure Al but higher than many structural alloys; important for conductor use
Specific Heat	~900 J/kg·K	Useful for thermal management calculations in electronics and forming processes
Thermal Expansion	23–24 µm/m·K (20–100 °C)	Similar to other aluminum alloys; relevant for thermal cycling and fittings design

The physical properties make 8079 attractive where thermal and electrical conductivity are important alongside forming performance. Density and modulus are essentially the same as other Al alloys, giving favorable strength-to-weight ratios for many applications.

Thermal conductivity and electrical conductivity are strongly influenced by the degree of alloying and cold working; suppliers will often provide measured conductivity for a given coil or sheet lot for applications sensitive to these parameters.

Product Forms

Form	Typical Thickness/Size	Strength Behavior	Common Tempers	Notes
Sheet	0.2–6.0 mm	Strength increases with cold rolling; thinner gauges show higher apparent strength	O, H12, H14, H18	Widely used for packaging, panels and formed components
Plate	>6.0 mm	Lower formability for thick plate; larger grain sizes can reduce toughness	O, designed H‑tempers	Less common; used where thicker sections are required with subsequent machining
Extrusion	Variable	Strength depends on alloy modifications and extrusion strain	H‑tempers after solution/aging if modified	Standard 8079 is rarely used for complex extrusions unless supplier-modified
Tube	Custom	Cold work and drawing increase strength; wall thickness affects yield	O, H‑tempers	Used for lightweight conduit, heat-exchange elements and packaging cores
Bar/Rod	Various diameters	Typically drawn/rolled with corresponding strength increases	H‑tempers	Less common; used in non-structural components and conductive parts

Processing route strongly affects final properties of 8079; rolling schedules, anneal temperatures and controlled cooling set grain size and texture that govern formability and springback. Sheet and strip are dominant product forms, produced to tight thickness and surface finish tolerances for packaging and decorative applications.

Extrusions and plate require either modified chemistries or careful control of homogenization and hot-working schedules to avoid coarse intermetallics; when used, they are typically for non-critical structural parts where corrosion resistance and surface quality are priorities.

Equivalent Grades

Standard	Grade	Region	Notes
AA	8079	USA	Recognized commercial designation used by several manufacturers for packaging sheet/foil
EN AW	—	Europe	No universal single EN AW equivalent; several 8xxx family grades (e.g., 8006, 8011) occupy similar space
JIS	—	Japan	Local equivalents not universally standardized; confirm supplier certification
GB/T	—	China	Chinese standards may use family grades; exact 8079 equivalent requires manufacturer datasheet

There is no always-direct one-to-one international standard equivalent for 8079 because it is frequently a commercial, application‑driven designation rather than a tightly standardized structural alloy. Suppliers and regional standards organizations may map 8079 to nearest 8xxx family grades, but composition limits and permitted tempers can differ.

Engineers should consult mill certificates and product data sheets when substituting between regions, particularly where electrical conductivity, surface finish and formability tolerances are critical.

Corrosion Resistance

8079 exhibits good general atmospheric corrosion resistance typical of low-alloy aluminum, forming a stable oxide film that protects the substrate in mild environments. It performs well in indoor and rural/urban atmospheres and resists pitting in moderately aggressive conditions when free of surface contaminants and with appropriate pre- and post-treatment (e.g., cleaning, conversion coatings).

In marine atmospheres 8079 is susceptible to localized corrosion if chloride deposition is persistent and if protective films are compromised. For marine use, attention must be paid to surface finishes, coatings and alloy selection; thicker sections and sacrificial design practices mitigate long-term risk. Stress corrosion cracking (SCC) is not a common failure mode for low-alloy 8xxx types like 8079 under typical service conditions, but aggressive environments combined with tensile stress and certain tempers can elevate risk.

Galvanic interactions with dissimilar metals follow usual aluminum behavior: 8079 is anodic relative to stainless steels and copper alloys and cathodic relative to magnesium. Isolation coatings or sacrificial anodes are recommended in mixed-metal assemblies. Compared with 5xxx magnesium-alloy series, 8079 generally offers similar to slightly reduced chloride resistance but superior formability and surface quality relative to higher-strength aluminum-magnesium alloys.

Fabrication Properties

Weldability

Fusion welding (TIG/MIG) of 8079 is generally straightforward due to low alloy content and good solidification characteristics. Use of 4xxx-series Al‑Si or 5xxx-series Al‑Mg fillers is common depending on desired strength and corrosion performance, with 4043 and 5356 being typical choices; filler selection should consider service environment and post‑weld anodizing requirements. Hot-cracking risk is low but can occur at high restraint and with poor joint fit-up; preheating is rarely necessary but good joint cleanliness and control of heat input are important to limit HAZ softening.

Machinability

Machinability of 8079 is moderate to good; it machines more easily than higher-strength alloys but is less free-cutting than very pure commercial grades. Carbide tooling with positive rake angles and rigid fixturing are recommended for milling and turning; high-feed, low-depth cuts produce the best surface and reduced built-up edge. Chip control is generally manageable; coolant helps prevent sticking and improves surface finish.

Formability

Formability is one of the principal strengths of 8079, especially in O and light H tempers where it supports deep drawing, roll forming and complex stamping. Recommended minimum bend radii depend on temper and thickness but are generally small (e.g., internal bend radii of 0.5–1.0× thickness for many sheet tempers); empirical testing is advised for critical geometries. Cold work increases strength but reduces ductility; counter‑measures such as intermediate anneals can restore formability for multi‑stage forming operations.

Heat Treatment Behavior

8079 is effectively a non-heat‑treatable alloy in standard commercial compositions; strength modifications are achieved through cold work (strain hardening) and thermal annealing cycles. Solution treatment and artificial aging (the T‑series route) are not generally applicable because the alloy lacks significant precipitate-forming alloying elements at useful concentrations.

Annealing is used to restore ductility and recrystallize the microstructure; industrial anneals are typically carried out at temperatures around 300–415 °C depending on thickness and desired grain size, followed by controlled cooling. For suppliers offering proprietary modified chemistries, limited solution treatment and aging may be specified—these are exception cases and must be treated according to mill datasheets. Work hardening by controlled rolling and drawing is the standard way to achieve H‑tempers, with predictable increases in yield and UTS proportional to percent cold reduction.

High-Temperature Performance

At elevated temperatures, 8079 loses strength progressively above ~100–150 °C and significant softening occurs as temperatures approach typical annealing ranges. Long‑term exposure near 200–300 °C can induce microstructural recovery and grain growth, reducing mechanical performance and dimensional stability. Oxidation is limited to the normal formation of aluminum oxide layers; however, loss of mechanical properties rather than surface oxidation is the primary limitation for sustained high-temperature use.

The heat-affected zone (HAZ) during welding can exhibit local softening due to annealing effects; design must account for reduced local strengths and potential distortion. For high-temperature structural applications, 8079 is typically not the material of choice; higher‑temperature aluminum alloys or alternative materials should be selected for sustained elevated-temperature loadings.

Applications

Industry	Example Component	Why 8079 Is Used
Packaging	Flexible and laminated foil, vacuum-formed lids	Excellent formability, surface finish and consistent rolling behavior
Automotive	Interior trim panels, decorative components	High formability and good surface quality for stamped and painted parts
Marine	Non-structural housings, trim	Adequate corrosion resistance and light weight for exposed components
Electronics	Heat spreaders, conductive foils	Good thermal and electrical conductivity with formability for thin foils
Construction	Flashings, cladding trims	Ease of forming and corrosion resistance for architectural details

8079 finds its strongest use in packaging and thin-gauge forming applications where surface quality, ductility and conductivity are paramount. Its combination of low alloy content and carefully controlled processing makes it a go-to material for deep drawing, foil production and other high-strain forming processes.

Designers opt for 8079 when the application prioritizes formability and surface characteristics over maximal strength, and where conductivity or thermal performance offers an added functional benefit.

Selection Insights

Select 8079 when your priority is deep drawability, surface finish and thermal/electrical conductivity over peak structural strength. It is ideal for packaging foil, thin-gauge formed parts and conductive foils where cleanliness and surface appearance matter.

Compared with commercially pure aluminum (e.g., 1100), 8079 trades off a small amount of conductivity and marginally higher cost for improved rolling stability, controlled mechanical strength and better process reliability in thin gauges. Against work‑hardened alloys such as 3003 or 5052, 8079 typically offers similar or better formability with comparable corrosion resistance but lower potential peak strength. Compared with heat‑treatable alloys like 6061 or 6063, 8079 will have lower maximum achievable strength but superior formability and often better surface finish for thin sheet; choose 8079 when forming complexity and surface quality outweigh the need for high structural strength.

Closing Summary

Aluminum 8079 remains a valuable material in modern engineering for applications demanding high formability, consistent surface quality and good thermal/electrical conductivity. Its controlled low-alloy chemistry and predictable response to cold work make it a practical choice for packaging, thin-gauge forming and non‑structural components where manufacturability and finish are critical.