Aluminum 2198
AA 2198 · UNS A92198
2198 (UNS A92198) is a widely adopted third-generation Al-Cu-Li sheet alloy in the 2000-series family, supplied in O, T3/T351, T4 and T8-type tempers (T8, T81, T851, T8511).
Reference datasheet — 2198 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the T8 condition
2198 tempers and conditions
2198 is supplied in 8 conditions, soft to hard. T8 is the default FabDigit quotes; the values on this page are for it.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Softest condition for severe forming or intermediate processing; must be re-solution treated and aged for service strength. | 130 | 250 | 22 | 70 HB | 35 % IACS |
Solution heat treated and naturally aged | Unstretched naturally aged condition used for formed details before final artificial ageing. | 230 | 360 | 22 | 100 HB | 23 % IACS |
Solution heat treated, cold worked and naturally aged | Formable sheet condition for skins that will be stretch-formed or bent, then optionally aged to T8. | 270 | 395 | 20 | 110 HB | 23 % IACS |
T3, stress relieved by stretching | Low-residual-stress plate for machined parts that will be aged after rough machining, or used as-is for high-toughness applications. | 280 | 405 | 18 | 115 HB | 23 % IACS |
Solution treated, ~1 % cold worked and artificially aged | Thin-gauge variant of the aged temper where only light stretching is applied; slightly lower strength, better flatness. | 415 | 470 | 10 | 142 HB | 28 % IACS |
T8Default Solution heat treated, cold worked and artificially aged | Standard supply condition for 2198 fuselage/skin sheet: peak-strength, damage-tolerant, corrosion-stable. | 430 | 480 | 11 | 145 HB | 28 % IACS |
T8, stress relieved by stretching | Peak-aged, low-residual-stress plate for machined ribs, floor beams and integrally machined panels. | 450 | 500 | 8 | 152 HB | 29 % IACS |
Extruded, stretched and artificially aged | Extruded stringers and stiffeners in peak-aged condition where straightness and low residual stress matter. | 470 | 510 | 8 | 155 HB | 29 % IACS |
What is 2198?
2198 (UNS A92198) is a widely adopted third-generation Al-Cu-Li sheet alloy in the 2000-series family, supplied in O, T3/T351, T4 and T8-type tempers (T8, T81, T851, T8511). It is used for fuselage skin and other thin aerospace structure where it saves weight against 2024, giving 430 MPa yield, 480 MPa tensile, 11% elongation and 145 HB with 100 W/m·K conductivity and 28% IACS. It has the best corrosion resistance (48) and formability (40) of the Al-Li grades listed, but is limited to 120 °C service and is not suited to conventional MIG/TIG welding. 2024-T3 sheet remains the lower-cost, more widely available alternative. 2198 has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 560°C (1,040 °F). 2198 has a yield strength of 430 MPa (62.4 ksi) and a tensile strength of 480 MPa (69.6 ksi) — stronger than 90% of aluminum grades. Elongation at break is 11% and the elastic modulus is 76 GPa (11 Msi).
What is 2198 used for?
- Fuselage skin
- Aerospace sheet structure
- Laser-welded stiffened skin panels
- Lower wing skin panels
- Formed frames and clips
- Extruded stringers for welded panels
Advantages
- Tough — resists crack growth — 38 MPa·√m (34.6 ksi·√in), better than 96% of aluminum grades
- High strength — 430 MPa (62.4 ksi), better than 90% of aluminum grades
Limitations
- Poor heat conductor — 100 W/m·K (57.8 BTU/hr·ft·°F), worse than 93% of aluminum grades
- Low electrical conductivity — 28 % IACS, worse than 82% of aluminum grades
- Limited service temperature — 120°C (248 °F), worse than 79% of aluminum grades
2198 properties
Typical room-temperature values for 2198-T8; bars are the position among aluminum grades.
Physical3
2198 has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 560°C (1,040 °F).
Mechanical14
2198 has a yield strength of 430 MPa (62.4 ksi) and a tensile strength of 480 MPa (69.6 ksi) — stronger than 90% of aluminum grades. Elongation at break is 11% and the elastic modulus is 76 GPa (11 Msi).
Thermal6
2198 is rated for continuous service to 120°C (248 °F). It conducts heat at 100 W/m·K (57.8 BTU/hr·ft·°F), worse than 93% of aluminum grades. Thermal expansion is 23 µm/m·K (12.8 µin/in·°F).
Electrical3
2198 conducts electricity at 28 % IACS, worse than 82% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (48/100), worse than 58% of aluminum grades.
Sustainability4
Producing a kilogram of 2198 takes about 215 MJ of energy and emits 13.5 kg of CO₂ — more than 93% of aluminum grades. Typical recycled content is 5%.
Manufacturability8
2198's machinability is good (60/100, worse than 51% of aluminum grades); weldability poor (30/100); formability fair (40/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the aluminum family
Yield strength against density for every aluminum grade FabDigit runs. 2198 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 2198
Is 2198 easy to machine?
Machines like a hard 2000 series: sharp polished-flute carbide, high speed, generous coolant; T8/T851 gives good chip control, but keep Li-bearing fines wet and segregated from other Al swarf.
Can 2198 be welded?
Not recommended for conventional MIG/TIG (hot cracking, Li oxidation); friction stir welding and laser beam welding with 4047/4000-series-type filler are the qualified joining routes, otherwise rivet/bolt.
Can 2198 be formed, bent or molded?
Form in T3/T4/O; T8 has limited bend ductility and pronounced planar anisotropy, so orient blanks to rolling direction and allow generous bend radii.
2198 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.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Cu | 2.9 – 3.5 | 3.2 |
| Liprincipal density-reducing / modulus-raising addition | 0.8 – 1.1 | 0.95 |
| Mg | 0.25 – 0.8 | 0.5 |
| Agpromotes fine T1 precipitation | 0.1 – 0.5 | 0.3 |
| Zrgrain-structure control | 0.04 – 0.18 | 0.11 |
| Mn | ≤ 0.5 | |
| Zn | ≤ 0.35 | |
| Ti | ≤ 0.1 | |
| Feimpurity limit | ≤ 0.1 | |
| Siimpurity limit | ≤ 0.08 | |
| Others (each) | ≤ 0.05 | |
| Others (total) | ≤ 0.15 | |
| Al | balance |
What surface finishes work on 2198?
Standard aerospace chain: alkaline clean, deoxidize, tartaric-sulfuric or chromic anodize, chromate-free conversion coat plus epoxy primer; avoid bare contact with steel or CFRP without sealant.
Surface treatments FabDigit runs on aluminum parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Equivalent designations
Standards and trade names that resolve to Aluminum 2198 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- A92198
How much does 2198 cost?
2198 is a high-cost aluminum ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
2198 — frequently asked
What is 2198 used for?
2198 is typically used for fuselage skin, aerospace sheet structure, laser-welded stiffened skin panels, lower wing skin panels, formed frames and clips and extruded stringers for welded panels. In short: most formable Al-Li sheet here; weight saving over 2024; laser and FSW weldable.
What is the yield strength of 2198?
2198 has a typical yield strength of 430 MPa (62.4 ksi) and a tensile strength of 480 MPa (69.6 ksi) — stronger than 90% of aluminum grades. Strength varies by condition: see the 8 listed tempers.
Is 2198 easy to machine?
Reasonably — machinability is rated good (60/100, worse than 51% of aluminum grades). Machines like a hard 2000 series: sharp polished-flute carbide, high speed, generous coolant; T8/T851 gives good chip control, but keep Li-bearing fines wet and segregated from other Al swarf.
Can 2198 be welded?
Not readily — weldability is rated poor (30/100). Not recommended for conventional MIG/TIG (hot cracking, Li oxidation); friction stir welding and laser beam welding with 4047/4000-series-type filler are the qualified joining routes, otherwise rivet/bolt.
What surface finishes work on 2198?
Standard aerospace chain: alkaline clean, deoxidize, tartaric-sulfuric or chromic anodize, chromate-free conversion coat plus epoxy primer; avoid bare contact with steel or CFRP without sealant.
Can 2198 be formed, bent or molded?
Form in T3/T4/O; T8 has limited bend ductility and pronounced planar anisotropy, so orient blanks to rolling direction and allow generous bend radii.
What is the maximum service temperature of 2198?
2198 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 2198-T8 and 2198-O?
T8 is the default condition — standard supply condition for 2198 fuselage/skin sheet: peak-strength, damage-tolerant, corrosion-stable. O: softest condition for severe forming or intermediate processing; must be re-solution treated and aged for service strength. Yield strength is 430 MPa in T8 versus 130 MPa in O.
How much does 2198 cost?
2198 is a high-cost aluminum ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
- AIRWARE 2198 sheet/plate technical data — Constellium (2021)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- MMPDS — Metallic Materials Properties Development and Standardization (Al-Li chapters) — Battelle/FAA (2023)
- AMS 4472 / AMS 4473 — Aluminum-Lithium alloy sheet and plate — SAE International (2019)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.