Aluminum 4004
AA 4004 · UNS A94004 · EN AW-4004, AlSi10Mg1.5
4004 (A94004, EN AW-4004, AlSi10Mg1.5) is a high-silicon Al-Si brazing alloy with 1.5 % Mg, used as the low-melting cladding layer on fin and tube stock for vacuum brazed heat exchangers.
Reference datasheet — 4004 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
4004 tempers and conditions
4004 is supplied in 7 conditions, soft to hard. O is the default FabDigit quotes; the values on this page are for it.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
after vacuum brazing thermal cycle (~600 °C) | Condition of the solidified 4004 fillet/clad after the brazing cycle; fully annealed, coarse Si structure, use for joint-strength design. | 75 | 170 | 6 | 55 HB | 40 % IACS |
ODefault Annealed | Default supply condition for 4004 braze foil and roll-bonded clad brazing sheet; maximum formability before the brazing cycle. | 90 | 200 | 10 | 60 HB | 38 % IACS |
Strain hardened, quarter hard | Light cold work for slightly stiffer fin/clad strip that still needs to be corrugated. | 155 | 225 | 7 | 70 HB | 37 % IACS |
Strain hardened, half hard | Most common hard condition for 4004-clad brazing sheet supplied for fin forming and stamped plates. | 195 | 250 | 5 | 80 HB | 37 % IACS |
Strain hardened, three-quarter hard | Stiffer strip where fin collapse resistance during brazing matters more than bend ductility. | 225 | 270 | 4 | 88 HB | 37 % IACS |
Strain hardened, full hard | Full-hard thin foil/strip supplied as-rolled without interanneal; maximum strength, minimum ductility. | 255 | 290 | 3 | 95 HB | 37 % IACS |
Strain hardened, extra hard | Very thin heavily cold-rolled braze foil used as a free-standing interlayer shim in vacuum brazing. | 280 | 310 | 2 | 100 HB | 37 % IACS |
What is 4004?
4004 (A94004, EN AW-4004, AlSi10Mg1.5) is a high-silicon Al-Si brazing alloy with 1.5 % Mg, used as the low-melting cladding layer on fin and tube stock for vacuum brazed heat exchangers. Engineers choose it for good filler flow and useful as-brazed strength — 90 MPa yield, 200 MPa tensile, 10 % elongation, 60 HB, 155 W/m·K and 38 % IACS — and it ships as clad brazing sheet and fin stock rather than as a structural mill product. The high Si content makes it abrasive to cut (machinability score 30) and difficult to weld or bright-anodize, and service is limited to about 150 °C. Use 4045 where a Mg-free filler is needed for flux or controlled-atmosphere brazing. 4004 has a density of 2.66 g/cm³ (0.0961 lb/in³), lighter than 84% of aluminum grades. It melts at 559°C (1,038 °F). 4004 has a yield strength of 90 MPa (13.1 ksi) and a tensile strength of 200 MPa (29 ksi) — weaker than 87% of aluminum grades. Elongation at break is 10% and the elastic modulus is 71 GPa (10.3 Msi).
What is 4004 used for?
- automotive radiator/HVAC brazing clad sheet
- vacuum brazed heat exchangers
- clad fin stock
Limitations
- Hard to polish — 35/100, worse than 98% of aluminum grades
- Difficult to machine — 30/100, worse than 92% of aluminum grades
- Low strength — 90 MPa (13.1 ksi), worse than 87% of aluminum grades
4004 properties
Typical room-temperature values for 4004-O; bars are the position among aluminum grades.
Physical3
4004 has a density of 2.66 g/cm³ (0.0961 lb/in³), lighter than 84% of aluminum grades. It melts at 559°C (1,038 °F).
Mechanical10
4004 has a yield strength of 90 MPa (13.1 ksi) and a tensile strength of 200 MPa (29 ksi) — weaker than 87% of aluminum grades. Elongation at break is 10% and the elastic modulus is 71 GPa (10.3 Msi).
Thermal6
4004 is rated for continuous service to 150°C (302 °F). It conducts heat at 155 W/m·K (89.6 BTU/hr·ft·°F), better than 71% of aluminum grades. Thermal expansion is 20.5 µm/m·K (11.4 µin/in·°F).
Electrical3
4004 conducts electricity at 38 % IACS, better than 61% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (55/100), worse than 51% of aluminum grades.
Sustainability4
Producing a kilogram of 4004 takes about 200 MJ of energy and emits 12 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 25%.
Manufacturability8
4004's machinability is poor (30/100, worse than 92% of aluminum grades); weldability good (55/100); formability good (55/100).
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. 4004 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 4004
Is 4004 easy to machine?
Rarely machined; when required use PCD or diamond-coated carbide, high speed and flood coolant because ~10 % primary/eutectic Si is very abrasive.
Can 4004 be welded?
Mainly used as a braze filler; GTAW/GMAW is possible but the 1–2 % Mg with 10 % Si makes the deposit hot-short and porosity-prone, so pre-clean and keep heat input low.
Can 4004 be formed, bent or molded?
Form in O or H12 temper — clad brazing sheet corrugates and stamps well, but bend radii must be generous in H16/H18 since the Si-rich layer cracks readily.
4004 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 |
|---|---|---|
| Sisets the low melting range | 9 – 10.5 | 9.8 |
| Mgoxide getter for fluxless vacuum brazing | 1 – 2 | 1.5 |
| Fe | ≤ 0.8 | |
| Cu | ≤ 0.25 | |
| Mn | ≤ 0.1 | |
| Zn | ≤ 0.2 | |
| Others (each) | ≤ 0.05 | |
| Others (total) | ≤ 0.15 | |
| Al | balance |
What surface finishes work on 4004?
Do not decorative-anodize (dark grey, blotchy); after brazing, the surface is normally left as-brazed, chromate-free conversion coated, or e-coated for corrosion protection.
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 4004 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- A94004
- EN / DIN / Werkstoff-Nr.
- AW-4004AlSi10Mg1.5
- Also called
- BAlSi-7
How much does 4004 cost?
4004 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.
4004 — frequently asked
What is 4004 used for?
4004 is typically used for automotive radiator/HVAC brazing clad sheet, vacuum brazed heat exchangers and clad fin stock. In short: vacuum brazing clad layer; low melting Al-Si filler; not a structural mill product.
What is the yield strength of 4004?
4004 has a typical yield strength of 90 MPa (13.1 ksi) and a tensile strength of 200 MPa (29 ksi) — weaker than 87% of aluminum grades. Strength varies by condition: see the 7 listed tempers.
Is 4004 easy to machine?
Not especially — machinability is rated poor (30/100, worse than 92% of aluminum grades). Rarely machined; when required use PCD or diamond-coated carbide, high speed and flood coolant because ~10 % primary/eutectic Si is very abrasive.
Can 4004 be welded?
Yes — weldability is rated good (55/100). Mainly used as a braze filler; GTAW/GMAW is possible but the 1–2 % Mg with 10 % Si makes the deposit hot-short and porosity-prone, so pre-clean and keep heat input low.
What surface finishes work on 4004?
Do not decorative-anodize (dark grey, blotchy); after brazing, the surface is normally left as-brazed, chromate-free conversion coated, or e-coated for corrosion protection.
Can 4004 be formed, bent or molded?
Form in O or H12 temper — clad brazing sheet corrugates and stamps well, but bend radii must be generous in H16/H18 since the Si-rich layer cracks readily.
What is the maximum service temperature of 4004?
4004 is rated for continuous use to about 150°C (302 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 4004-O and 4004-H19?
O is the default condition — default supply condition for 4004 braze foil and roll-bonded clad brazing sheet; maximum formability before the brazing cycle. H19: very thin heavily cold-rolled braze foil used as a free-standing interlayer shim in vacuum brazing. Yield strength is 90 MPa in O versus 280 MPa in H19.
How much does 4004 cost?
4004 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)
- AWS A5.8/A5.8M — Specification for Filler Metals for Brazing and Braze Welding (BAlSi-7) — AWS (2019)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering (Aluminum Brazing) — ASM International (1993)
- Aluminium brazing sheet / cladding alloy data (4004, 4104, 4343) — Multiple rolling mills (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.