Aluminum 6951
AA 6951 · UNS A96951 · EN AW-6951
6951 is a lean Al-Mg-Si brazing-sheet core alloy (UNS A96951, EN AW-6951), normally rolled with an Al-Si clad layer into fin and tube stock for brazed heat exchangers.
Reference datasheet — 6951 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 O condition
6951 tempers and conditions
6951 is supplied in 12 conditions, soft to hard. O is the default FabDigit quotes; the values on this page are for it.
Compare all 12 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ODefault Annealed | Standard condition for clad brazing sheet that will be roll-formed into tubes/fins and then furnace brazed. | 41 | 110 | 30 | 28 HB | 50 % IACS |
As-brazed (post-CAB, naturally aged core) | The real in-service state of radiator/condenser tubes: core recrystallised by the 595–605 °C braze cycle, then naturally aged for weeks. | 70 | 165 | 20 | 45 HB | 46 % IACS |
Strain hardened, quarter hard | Light temper rolling when slightly stiffer strip is needed but deep forming is still required. | 105 | 130 | 12 | 38 HB | 50 % IACS |
Solution heat treated by the user and naturally aged | Applies when the fabricator (not the mill) solution treats formed parts, e.g. after brazing and quench. | 110 | 205 | 22 | 58 HB | 44 % IACS |
Strain hardened and partially annealed, half hard | Half-hard strength with better bend ductility than H14 — preferred for folded (B-type) brazed tube. | 120 | 150 | 10 | 44 HB | 50 % IACS |
Solution heat treated and naturally aged | Formable but pre-strengthened condition; also approximates the state of brazed parts after natural aging. | 125 | 220 | 20 | 62 HB | 43 % IACS |
Strain hardened, half hard | Common as-rolled coil temper for high-speed fin mills and welded-tube stock. | 130 | 150 | 8 | 45 HB | 50 % IACS |
Strain hardened, three-quarter hard | Stiffer strip for narrow fin stock where limited bending is acceptable. | 160 | 175 | 5 | 52 HB | 50 % IACS |
Cooled from hot working and artificially aged | Used when the braze-furnace exit cooling is fast enough to act as a quench, followed by a low-temperature age. | 170 | 210 | 12 | 68 HB | 46 % IACS |
Strain hardened, full hard | Maximum cold-worked strength; used where the strip is only slit and corrugated, not deep drawn. | 185 | 200 | 3 | 58 HB | 50 % IACS |
T6, heat treated by the user | Same target properties as T6 but achieved by heat treating O/H-temper material after fabrication or brazing. | 215 | 260 | 12 | 80 HB | 45 % IACS |
Solution heat treated and artificially aged | Peak-strength condition for structural sheet or for brazed assemblies that are re-solution treated and aged. | 230 | 270 | 13 | 82 HB | 45 % IACS |
What is 6951?
6951 is a lean Al-Mg-Si brazing-sheet core alloy (UNS A96951, EN AW-6951), normally rolled with an Al-Si clad layer into fin and tube stock for brazed heat exchangers. It is chosen for roll forming, fin corrugating and tube seaming, with 200 W/m·K thermal conductivity and about 50% IACS, and is available in O, H12–H18, H24, T4/T42, T5, T6/T62 and as-brazed condition. Strength is low — 41 MPa yield, 110 MPa tensile, 30% elongation and 28 HB annealed — service is limited to 200 °C, and the clad layer anodizes unevenly, so painted or conversion-coated finishes are preferred. Clad 3003 fin stock is the nearest alternative. 6951 has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 616°C (1,141 °F). 6951 has a yield strength of 41 MPa (5.95 ksi) and a tensile strength of 110 MPa (16 ksi) — weaker than 96% of aluminum grades. Elongation at break is 30% and the elastic modulus is 69 GPa (10 Msi).
What is 6951 used for?
- automotive radiators
- HVAC heat exchangers
- brazed fin/tube assemblies
Advantages
- Ductile — tolerates forming and impact — 30%, better than 96% of aluminum grades
- Forms and bends easily — 90/100, better than 93% of aluminum grades
- Conducts heat well — 200 W/m·K (115.6 BTU/hr·ft·°F), better than 91% of aluminum grades
- High service temperature — 200°C (392 °F), better than 90% of aluminum grades
- High electrical conductivity — 50 % IACS, better than 90% of aluminum grades
Limitations
- Low strength — 41 MPa (5.95 ksi), worse than 96% of aluminum grades
- Difficult to machine — 40/100, worse than 81% of aluminum grades
6951 properties
Typical room-temperature values for 6951-O; bars are the position among aluminum grades.
Physical3
6951 has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 616°C (1,141 °F).
Mechanical10
6951 has a yield strength of 41 MPa (5.95 ksi) and a tensile strength of 110 MPa (16 ksi) — weaker than 96% of aluminum grades. Elongation at break is 30% and the elastic modulus is 69 GPa (10 Msi).
Thermal6
6951 is rated for continuous service to 200°C (392 °F). It conducts heat at 200 W/m·K (115.6 BTU/hr·ft·°F), better than 91% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).
Electrical3
6951 conducts electricity at 50 % IACS, better than 90% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (58/100), better than 57% of aluminum grades.
Sustainability4
Producing a kilogram of 6951 takes about 200 MJ of energy and emits 12 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 30%.
Manufacturability8
6951's machinability is fair (40/100, worse than 81% of aluminum grades); weldability very good (72/100); formability excellent (90/100).
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. 6951 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 6951
Is 6951 easy to machine?
Soft and gummy in O/T4 — use polished high-rake carbide, high speed and flood or MQL lubricant; T6 chips break far better.
Can 6951 be welded?
Readily GTAW/GMAW welded with 4043 filler (4047 for the clad side); avoid 5000-series filler on the Al-Si clad layer and expect strength loss in the HAZ of aged tempers.
Can 6951 be formed, bent or molded?
Excellent roll forming, fin corrugating and tube seaming in O/H24; keep bend radii ≥1t in H18 and re-anneal or use T4 for deep draws.
6951 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 |
|---|---|---|
| Si | 0.2 – 0.5 | 0.35 |
| Feimpurity limit | ≤ 0.8 | 0.35 |
| Cu | 0.15 – 0.4 | 0.25 |
| Mn | ≤ 0.1 | 0.03 |
| Mg | 0.4 – 0.8 | 0.6 |
| Zn | ≤ 0.2 | 0.05 |
| Others (each) | ≤ 0.05 | |
| Others (total) | ≤ 0.15 | |
| Alremainder, ~98.3 % nominal | balance |
What surface finishes work on 6951?
Designed for CAB (Nocolok flux) or vacuum brazing at 590–605 °C; for corrosion protection use Zn arc-spray or chromate-free conversion coat plus e-coat rather than decorative anodizing, since the clad Al-Si layer anodizes unevenly.
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 6951 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- A96951
- EN / DIN / Werkstoff-Nr.
- AW-6951
How much does 6951 cost?
6951 is a premium-cost aluminum ($$$), cheaper than about 51% 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.
6951 — frequently asked
What is 6951 used for?
6951 is typically used for automotive radiators, HVAC heat exchangers and brazed fin/tube assemblies. In short: brazing-sheet core alloy; highest-formability 6000 series; heat-exchanger fin stock.
What is the yield strength of 6951?
6951 has a typical yield strength of 41 MPa (5.95 ksi) and a tensile strength of 110 MPa (16 ksi) — weaker than 96% of aluminum grades. Strength varies by condition: see the 12 listed tempers.
Is 6951 easy to machine?
Not especially — machinability is rated fair (40/100, worse than 81% of aluminum grades). Soft and gummy in O/T4 — use polished high-rake carbide, high speed and flood or MQL lubricant; T6 chips break far better.
Can 6951 be welded?
Yes — weldability is rated very good (72/100). Readily GTAW/GMAW welded with 4043 filler (4047 for the clad side); avoid 5000-series filler on the Al-Si clad layer and expect strength loss in the HAZ of aged tempers.
What surface finishes work on 6951?
Designed for CAB (Nocolok flux) or vacuum brazing at 590–605 °C; for corrosion protection use Zn arc-spray or chromate-free conversion coat plus e-coat rather than decorative anodizing, since the clad Al-Si layer anodizes unevenly.
Can 6951 be formed, bent or molded?
Excellent roll forming, fin corrugating and tube seaming in O/H24; keep bend radii ≥1t in H18 and re-anneal or use T4 for deep draws.
What is the maximum service temperature of 6951?
6951 is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 6951-O and 6951-T6?
O is the default condition — standard condition for clad brazing sheet that will be roll-formed into tubes/fins and then furnace brazed. T6: peak-strength condition for structural sheet or for brazed assemblies that are re-solution treated and aged. Yield strength is 41 MPa in O versus 230 MPa in T6.
How much does 6951 cost?
6951 is a premium-cost aluminum ($$$), cheaper than about 51% 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)
- ASTM B209 / B209M — Standard Specification for Aluminum and Aluminum-Alloy Sheet and Plate — ASTM International (2021)
- EN 573-3 / EN 485-2 — Aluminium and aluminium alloys: chemical composition and mechanical properties of sheet and strip — CEN (2019)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- ASM Specialty Handbook: Aluminum and Aluminum Alloys (brazing sheet chapter) — ASM International (1993)
- Aluminium brazing sheet product data (clad 4343/4045 on 6951/3003 core) — Rolled-product mills (e.g. Novelis / Granges / Constellium class data) (2022)
- MatWeb wrought aluminum 6951 temper property listings — MatWeb LLC (2023)
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.