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Aluminum 2199-T86

Temper

AA 2199 · UNS A92199

T86 = solution treated, cold worked ~6 % and artificially aged

Highest-strength condition for extrusions and stringers where toughness demand is lower.

High cost $$$$

Values for the T86 condition

Other 2199 tempers and conditions

2199 is listed in 6 conditions; see the grade overview at 2199.

Compare all 6 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
Annealed
Softest condition for deep forming or intermediate processing before re-solution treatment.1352502065 HB33 % IACS
T3, stress relieved by stretching
Plate condition with low residual stress for stable heavy machining before final ageing.26539517108 HB21 % IACS
Solution heat treated, cold worked and naturally aged
Naturally aged sheet used when parts must be formed or stretch-formed before final artificial ageing.27040018110 HB21 % IACS
T8E74Default
Solution treated, cold worked and artificially aged
Standard supplied condition for 2199 fuselage sheet — best balance of strength, toughness and damage tolerance.38545011130 HB24 % IACS
T8, stress relieved by stretching
Low-residual-stress plate temper for machined lower-wing panels and frames.4204709136 HB24 % IACS
T86This page
Solution treated, cold worked ~6 % and artificially aged
Highest-strength condition for extrusions and stringers where toughness demand is lower.4554908142 HB25 % IACS

What is 2199-T86?

2199-T86 is 2199 in the T86 temper — highest-strength condition for extrusions and stringers where toughness demand is lower. 2199-T86 has a yield strength of 455 MPa (66 ksi) and a tensile strength of 490 MPa (71.1 ksi) — stronger than 92% of aluminum grades. Elongation at break is 8% and the elastic modulus is 78 GPa (11.3 Msi). 2199-T86 has a density of 2.63 g/cm³ (0.095 lb/in³), lighter than 95% of aluminum grades. It melts at 545°C (1,013 °F). T8E74 is the default condition FabDigit quotes; T86 is available on request or by drawing note.

Advantages

  • High strength — 455 MPa (66 ksi), better than 92% of aluminum grades
  • Tough — resists crack growth — 32 MPa·√m (29.1 ksi·√in), better than 83% of aluminum grades

Limitations

  • Poor heat conductor — 94 W/m·K (54.3 BTU/hr·ft·°F), worse than 98% of aluminum grades
  • High embodied carbon — 14 kg CO₂/kg, worse than 95% of aluminum grades
  • Low electrical conductivity — 25 % IACS, worse than 92% of aluminum grades
  • Limited service temperature — 120°C (248 °F), worse than 79% of aluminum grades

2199-T86 properties

Typical room-temperature values for 2199-T86; 20 are specific to this condition. Other listed values are 2199 reference data and may not represent this condition. Bars are the position among aluminum grades.

Physical3

2199-T86 has a density of 2.63 g/cm³ (0.095 lb/in³), lighter than 95% of aluminum grades. It melts at 545°C (1,013 °F).

Density2.63 g/cm³0.1 lb/in³
Melting Point (Solidus)545°C1,013 °F
Liquidus Temperature650°C1,202 °F

Mechanical12

2199-T86 has a yield strength of 455 MPa (66 ksi) and a tensile strength of 490 MPa (71.1 ksi) — stronger than 92% of aluminum grades. Elongation at break is 8% and the elastic modulus is 78 GPa (11.3 Msi).

Elastic (Young's) Modulus78 GPa11.3 Msi
Shear Modulus29.5 GPa4.3 Msi
Bulk Modulus76 GPa11 Msi
Poisson's Ratio0.33
Tensile Strength (Ultimate)490 MPa71.1 ksi
Yield Strength (0.2% offset)455 MPa66 ksi
Elongation at Break8%
Shear Strength290 MPa42.1 ksi
Fatigue Strength (Endurance Limit)160 MPa23.2 ksi
Fracture Toughness (K_IC)32 MPa·√m29.1 ksi·√in
Hardness, Brinell142 HB
Hardness, Vickers152 HV

Thermal6

2199-T86 is rated for continuous service to 120°C (248 °F). It conducts heat at 94 W/m·K (54.3 BTU/hr·ft·°F), worse than 98% of aluminum grades. Thermal expansion is 22.3 µm/m·K (12.4 µin/in·°F).

Thermal Conductivity94 W/m·K54.3 BTU/hr·ft·°F
Specific Heat Capacity900 J/kg·K0.21 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)22.3 µm/m·K12.4 µin/in·°F
Latent Heat of Fusion390 J/g168 BTU/lb
Max Service Temperature (continuous)120°C248 °F
Min Service Temperature-253°C-423 °F

Electrical3

2199-T86 conducts electricity at 25 % IACS, worse than 92% of aluminum grades.

Electrical Conductivity25 % IACS
Electrical Resistivity6.9×10⁻⁸ Ω·m2.72 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is fair (42/100), worse than 69% of aluminum grades.

Galvanic Potential (seawater, vs SCE)-0.72 V
Corrosion ResistanceFair42/100
Chemical Resistance SummaryGood in dry atmospheres and neutral organics; vulnerable to chloride pitting, exfoliation in under-aged tempers and galvanic attack when coupled to CFRP or steel fasteners; avoid strong acids and alkalis.

Sustainability4

Producing a kilogram of 2199-T86 takes about 230 MJ of energy and emits 14 kg of CO₂ — more than 96% of aluminum grades. Typical recycled content is 5%.

Embodied Energy (primary production)230 MJ/kg98,882 BTU/lb
Embodied Carbon (primary production)14 kg CO₂/kg
Embodied Water1,200 L/kg144 gal/lb
Typical Recycled Content5%

Manufacturability8

2199-T86's machinability is good (58/100, worse than 54% of aluminum grades); weldability poor (30/100); formability poor (25/100).

MachinabilityGood58/100
Machinability Rating (AISI 1212 = 100 %)45%
WeldabilityPoor30/100
Formability (cold)Poor25/100
CastabilityPoor25/100
Brazeability / SolderabilityPoor15/100
PolishabilityGood55/100
Anodizing Responsefair to good — chromic and sulfuric acid anodize used on aerospace parts; Cu and Li give a slightly darker, less uniform film than 6000 series, so decorative anodizing is not recommended.

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with 2199-T86

Is 2199 easy to machine?

Machines like 2024-T8 with sharp PCD/carbide tooling and flood coolant; fine Al-Li chips and dust are reactive, so keep swarf dry, segregated and away from water or acid.

Can 2199 be welded?

Fusion welding is hot-crack and porosity prone; friction stir welding, laser-beam welding with dedicated Al-Li filler, or riveting/bonding are the accepted joining routes.

Can 2199 be formed, bent or molded?

Form in O or T3 temper then age to T8; the T8 condition has limited stretch and pronounced planar anisotropy, so bend radii and blank orientation must be controlled.

What surface finishes work on 2199?

Chromic or thin-film sulfuric anodize plus chromate-free primer is standard; alkaline etch times must be shortened because Li-bearing surfaces attack faster than 2024.

2199 chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
Liprimary density-reducing, modulus-raising addition1.4 – 1.81.6
Cu2.3 – 2.92.6
Znimproves corrosion behaviour0.2 – 0.90.6
Mn0.1 – 0.50.3
Mg0.05 – 0.40.2
Zrgrain-structure control (Al3Zr dispersoids)0.05 – 0.120.09
Ti≤ 0.1—
Feimpurity limit for toughness≤ 0.07—
Siimpurity limit for toughness≤ 0.05—
Others (each)≤ 0.05—
Others (total)≤ 0.15—
Albalance—

2199-T86 — frequently asked

What is 2199-T86 used for?

2199-T86 is typically used for fuselage sheet, aerospace skins, lower wing skin panels, damage-tolerant plate for frames, bonded and riveted skin assemblies and pressure cabin structure. In short: tougher companion to 2198; lithium-based weight reduction; damage-tolerant skin alloy.

What is the yield strength of 2199-T86?

2199-T86 has a typical yield strength of 455 MPa (66 ksi) and a tensile strength of 490 MPa (71.1 ksi) — stronger than 92% of aluminum grades. Strength varies by condition: see the 6 listed tempers.

Is 2199-T86 easy to machine?

Reasonably — machinability is rated good (58/100, worse than 54% of aluminum grades). Machines like 2024-T8 with sharp PCD/carbide tooling and flood coolant; fine Al-Li chips and dust are reactive, so keep swarf dry, segregated and away from water or acid.

Can 2199-T86 be welded?

Not readily — weldability is rated poor (30/100). Fusion welding is hot-crack and porosity prone; friction stir welding, laser-beam welding with dedicated Al-Li filler, or riveting/bonding are the accepted joining routes.

What surface finishes work on 2199-T86?

Chromic or thin-film sulfuric anodize plus chromate-free primer is standard; alkaline etch times must be shortened because Li-bearing surfaces attack faster than 2024.

Can 2199-T86 be formed, bent or molded?

Form in O or T3 temper then age to T8; the T8 condition has limited stretch and pronounced planar anisotropy, so bend radii and blank orientation must be controlled.

What is the maximum service temperature of 2199-T86?

2199-T86 is rated for continuous use to about 120°C (248 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between 2199 T8E74 and 2199-O?

T8E74 is the default condition — standard supplied condition for 2199 fuselage sheet — best balance of strength, toughness and damage tolerance. O: softest condition for deep forming or intermediate processing before re-solution treatment. Yield strength is 385 MPa in T8E74 versus 135 MPa in O.

Sources

  1. International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
  2. Alcoa third-generation Al-Li alloy product information (2199/2099/2060 family) — Alcoa / Arconic (2016)
  3. ASM Handbook Vol. 2: Properties and Selection — Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
  4. Aluminum-Lithium Alloys: Processing, Properties and Applications — Elsevier / Butterworth-Heinemann (2014)
  5. MMPDS-style typical property compilations for aerospace aluminium — Battelle (2021)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.