Aluminum 7039
AA 7039 · UNS A97039
7039 is a weldable, copper-free Al-Zn-Mg (7000 series) armor plate alloy specified under MIL-DTL-46063 and available in O, T6, T61, T63, T64, T651, T6351 and T7.
Values for the T6 condition
7039 tempers and conditions
7039 is supplied in 8 conditions, soft to hard. T6 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 machining before solution treatment and ageing. | 115 | 235 | 20 | 65 HB | 40 % IACS |
Solution heat treated and overaged (stabilized) | Overaged for maximum stress-corrosion and exfoliation resistance in thick sections or marine/humid service; ~10 % strength loss vs T6. | 330 | 400 | 13 | 118 HB | 40 % IACS |
T6 variant, underaged | Milder quench to limit distortion and residual stress in complex sections, at a small strength cost. | 345 | 415 | 13 | 122 HB | 36 % IACS |
Solution heat treated and underaged/two-step aged | Preferred armor temper: slightly lower strength than T6 but better toughness, spall resistance and stress-corrosion behaviour. | 345 | 415 | 13 | 122 HB | 37 % IACS |
Solution heat treated, stretched, aged | Thick-plate stress-relieved T6 variant used where symmetrical machining stability is critical. | 370 | 440 | 12 | 130 HB | 35 % IACS |
T6, stress relieved by stretching | T6 plate with controlled stretch for low residual stress — choose when heavy machining of thick plate is required. | 379 | 448 | 13 | 133 HB | 35 % IACS |
T6Default Solution heat treated and artificially aged | Highest strength condition; standard for welded high-strength structures where SCC exposure is controlled. | 380 | 450 | 13 | 133 HB | 35 % IACS |
Solution heat treated and specially aged | Armor-plate ageing practice balancing ballistic limit against back-face spall; specified in US armor plate specifications. | 385 | 450 | 12 | 132 HB | 36 % IACS |
What is 7039?
7039 is a weldable, copper-free Al-Zn-Mg (7000 series) armor plate alloy specified under MIL-DTL-46063 and available in O, T6, T61, T63, T64, T651, T6351 and T7. It is chosen where welded structures need more strength than 5000-series plate: 380 MPa yield, 450 MPa tensile, 13 % elongation and 133 HB with good arc weldability (score 75). Cold formability is poor (score 35), stress-corrosion cracking limits sustained tension across T6 weld heat-affected zones, and service is capped near 120 °C. 5083 plate is the usual alternative when weld-zone SCC is the governing risk. 7039 has a density of 2.74 g/cm³ (0.099 lb/in³), heavier than 64% of aluminum grades. It melts at 585°C (1,085 °F). 7039 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 450 MPa (65.3 ksi) — stronger than 86% of aluminum grades. Elongation at break is 13% and the elastic modulus is 69.6 GPa (10.1 Msi).
What is 7039 used for?
- Military vehicle armor plate
- Armored hull and cab structures
- Turret and hatch weldments
- Ballistic protection panels
- Armored personnel carrier bodies
- Welded military bridging and shelters
Advantages
- High strength — 380 MPa (55.1 ksi), better than 86% of aluminum grades
- Ductile — tolerates forming and impact — 13%, better than 79% of aluminum grades
- Tough — resists crack growth — 30 MPa·√m (27.3 ksi·√in), better than 76% of aluminum grades
Limitations
- Limited service temperature — 120°C (248 °F), worse than 79% of aluminum grades
7039 properties
Typical room-temperature values for 7039-T6; bars are the position among aluminum grades.
Physical3
7039 has a density of 2.74 g/cm³ (0.099 lb/in³), heavier than 64% of aluminum grades. It melts at 585°C (1,085 °F).
Mechanical12
7039 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 450 MPa (65.3 ksi) — stronger than 86% of aluminum grades. Elongation at break is 13% and the elastic modulus is 69.6 GPa (10.1 Msi).
Thermal6
7039 is rated for continuous service to 120°C (248 °F). It conducts heat at 154 W/m·K (89 BTU/hr·ft·°F), better than 68% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).
Electrical3
7039 conducts electricity at 35 % IACS, better than 52% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (42/100), worse than 69% of aluminum grades.
Sustainability4
Producing a kilogram of 7039 takes about 205 MJ of energy and emits 12.5 kg of CO₂ — more than 76% of aluminum grades. Typical recycled content is 20%.
Manufacturability8
7039's machinability is very good (70/100, better than 72% of aluminum grades); weldability very good (75/100); formability fair (35/100).
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. 7039 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 7039
Is 7039 easy to machine?
Machines like other aged 7000-series plate — high cutting speeds, sharp polished-flute carbide tooling and flood coolant give good chips; stress-relieved (T651) stock avoids warpage in deep pocketing.
Can 7039 be welded?
Designed for GMAW/GTAW with 5183/5356 (or 5039) filler; HAZ recovers a useful fraction of strength by natural ageing, but avoid sustained tensile stress across weld HAZ in T6 due to SCC risk.
Can 7039 be formed, bent or molded?
Form in O or freshly solution-treated (W) condition; T6/T64 plate has limited cold bending and needs generous bend radii or warm forming.
Manufacturability
The process limits FabDigit applies to 7039. Every 7039 part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Good70 / 100 |
|---|---|
| ISO material group | N.1 |
| Cutting speed (rough / finish) | 350 / 420 m/min |
| Minimum wall | 0.5 mm |
| Minimum internal radius | 1 mm |
| Drill depth limit | 8× diameter |
| Best surface (machined / polished) | Ra 0.8 / — |
| Hardenable after machining | No |
Sheet metal
| Formability | Fair35 / 100 |
|---|---|
| Weldability | Good75 / 100 |
7039 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 |
|---|---|---|
| Siimpurity limit | ≤ 0.3 | 0.1 |
| Feimpurity limit | ≤ 0.4 | 0.2 |
| Cukept low for weldability | ≤ 0.1 | 0.03 |
| Mn | 0.1 – 0.4 | 0.25 |
| Mg | 2.3 – 3.3 | 2.8 |
| Crgrain-structure control | 0.15 – 0.25 | 0.2 |
| Zn | 3.5 – 4.5 | 4 |
| Tigrain refiner | ≤ 0.1 | 0.03 |
| Others (each) | ≤ 0.05 | |
| Others (total) | ≤ 0.15 | |
| Al | balance |
What surface finishes work on 7039?
Takes clear, hard and chromate/anodic coatings well; for military use it is normally chemical-conversion coated and painted (CARC), and welds anodize a different shade than parent metal.
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).
Passivation
Conversion Coating
PVD Coating
Equivalent designations
Standards and trade names that resolve to Aluminum 7039 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- A97039
- Aluminum Association
- AA7039
How much does 7039 cost?
7039 is a premium-cost aluminum ($$$), pricier than about 57% 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.
7039 — frequently asked
What is 7039 used for?
7039 is typically used for military vehicle armor plate, armored hull and cab structures, turret and hatch weldments, ballistic protection panels, armored personnel carrier bodies and welded military bridging and shelters. In short: weldable 7000-series armor; marine and military.
What is the yield strength of 7039?
7039 has a typical yield strength of 380 MPa (55.1 ksi) and a tensile strength of 450 MPa (65.3 ksi) — stronger than 86% of aluminum grades. Strength varies by condition: see the 8 listed tempers.
Is 7039 easy to machine?
Yes — machinability is rated very good (70/100, better than 72% of aluminum grades). Machines like other aged 7000-series plate — high cutting speeds, sharp polished-flute carbide tooling and flood coolant give good chips; stress-relieved (T651) stock avoids warpage in deep pocketing.
Can 7039 be welded?
Yes — weldability is rated very good (75/100). Designed for GMAW/GTAW with 5183/5356 (or 5039) filler; HAZ recovers a useful fraction of strength by natural ageing, but avoid sustained tensile stress across weld HAZ in T6 due to SCC risk.
What surface finishes work on 7039?
Takes clear, hard and chromate/anodic coatings well; for military use it is normally chemical-conversion coated and painted (CARC), and welds anodize a different shade than parent metal.
Can 7039 be formed, bent or molded?
Form in O or freshly solution-treated (W) condition; T6/T64 plate has limited cold bending and needs generous bend radii or warm forming.
What is the maximum service temperature of 7039?
7039 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 7039-T6 and 7039-O?
T6 is the default condition — highest strength condition; standard for welded high-strength structures where SCC exposure is controlled. O: softest condition for severe forming or machining before solution treatment and ageing. Yield strength is 380 MPa in T6 versus 115 MPa in O.
How much does 7039 cost?
7039 is a premium-cost aluminum ($$$), pricier than about 57% 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.
Can FabDigit make parts in 7039?
Yes — 7039 is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
- MIL-DTL-46063H — Armor Plate, Aluminum Alloy 7039 — US DoD (1998)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol. 19 — Fatigue and Fracture — ASM International (1996)
- ASM Handbook Vol. 13B — Corrosion: Materials — ASM International (2005)
- MMPDS-style typical mechanical data for 7000-series wrought products — Battelle/FAA (2023)
- SMM / Mysteel (2026)
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.