Aluminum ER4045
ASTM AWS A5.10 ER4045 · EN S Al 4045
ER4045 is a near-eutectic Al-10%Si filler and cladding alloy (AWS A5.10 ER4045, S Al 4045, SAlSi-3) with a lower melting range than ER4043.
Reference datasheet — ER4045 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 AW condition
ER4045 tempers and conditions
ER4045 is supplied in 5 conditions, soft to hard. AW is the default FabDigit quotes; the values on this page are for it.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Choose for soft, fully annealed 4045 clad strip or foil that must be formed or roll-bonded before brazing. | 45 | 110 | 24 | 35 HB | 43 % IACS |
As built (as printed) | Use for the re-solidified Al-Si fillet/clad layer in a finished brazed heat exchanger joint. | 55 | 130 | 8 | 48 HB | 40 % IACS |
AWDefault As-welded deposit | Default condition: properties of the ER4045 deposit as laid down by TIG/MIG on aluminium base metal. | 60 | 165 | 12 | 45 HB | 41 % IACS |
Strain hardened, half hard | Half-hard 4045 strip/foil for brazing shims and preforms needing handling stiffness with some formability. | 125 | 150 | 6 | 50 HB | 42 % IACS |
Strain hardened, full hard | Full-hard thin foil/shim stock for flat brazing preforms that are stamped, not formed. | 170 | 190 | 3 | 60 HB | 41 % IACS |
Supply forms, finishes and certifications
Ways ER4045 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
F-WIRE | F | Supply form |
What is ER4045?
ER4045 is a near-eutectic Al-10%Si filler and cladding alloy (AWS A5.10 ER4045, S Al 4045, SAlSi-3) with a lower melting range than ER4043. It is used mainly as the braze cladding roll-bonded onto 3000-series-core brazing sheet for heat exchangers, and as a TIG/MIG filler for thin 3000/6000 series sheet and Al-Si castings; conditions on file include AW, F-WIRE, O, H14, H18 and AB. Deposits are soft at about 60 MPa yield, 165 MPa tensile and 12 % elongation, and the alloy is unsuitable for 5000-series base metal above 2.5 % Mg or for cosmetic anodizing. ER4043 is the alternative when a higher melting range is acceptable. ER4045 has a density of 2.67 g/cm³ (0.0965 lb/in³), lighter than 78% of aluminum grades. It melts at 577°C (1,071 °F). ER4045 has a yield strength of 60 MPa (8.7 ksi) and a tensile strength of 165 MPa (23.9 ksi) — weaker than 93% of aluminum grades. Elongation at break is 12% and the elastic modulus is 71 GPa (10.3 Msi).
What is ER4045 used for?
- brazing sheet cladding
- heat exchanger fabrication
- TIG welding of thin sheet
Advantages
- Readily welded — 92/100, better than 95% of aluminum grades
- Conducts heat well — 165 W/m·K (95.3 BTU/hr·ft·°F), better than 79% of aluminum grades
- High electrical conductivity — 41 % IACS, better than 78% of aluminum grades
Limitations
- Hard to polish — 38/100, worse than 97% of aluminum grades
- Low strength — 60 MPa (8.7 ksi), worse than 93% of aluminum grades
- Difficult to machine — 42/100, worse than 77% of aluminum grades
ER4045 properties
Typical room-temperature values for ER4045-AW; bars are the position among aluminum grades.
Physical3
ER4045 has a density of 2.67 g/cm³ (0.0965 lb/in³), lighter than 78% of aluminum grades. It melts at 577°C (1,071 °F).
Mechanical15
ER4045 has a yield strength of 60 MPa (8.7 ksi) and a tensile strength of 165 MPa (23.9 ksi) — weaker than 93% of aluminum grades. Elongation at break is 12% and the elastic modulus is 71 GPa (10.3 Msi).
Thermal6
ER4045 is rated for continuous service to 150°C (302 °F). It conducts heat at 165 W/m·K (95.3 BTU/hr·ft·°F), better than 79% of aluminum grades. Thermal expansion is 21.3 µm/m·K (11.8 µin/in·°F).
Electrical3
ER4045 conducts electricity at 41 % IACS, better than 78% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (58/100), better than 57% of aluminum grades.
Sustainability4
Producing a kilogram of ER4045 takes about 200 MJ of energy and emits 12 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 25%.
Manufacturability8
ER4045's machinability is fair (42/100, worse than 77% of aluminum grades); weldability excellent (92/100); 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. ER4045 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with ER4045
Is ER4045 easy to machine?
Rarely machined; the ~10% Si makes it abrasive — use PCD or polished carbide, high speed, low feed, generous coolant.
Can ER4045 be welded?
Excellent as a filler for 3000/6000 series and cast Al-Si; use AC-TIG or pulsed MIG, keep heat input low, never for 5000 series with >2.5% Mg (brittle Mg2Si) or for parts to be anodized cosmetically.
Can ER4045 be formed, bent or molded?
Very fluid on melting (near-eutectic), ideal for capillary brazing gaps of 0.05–0.15 mm; as strip it is roll-clad onto 3003/3000-series core rather than formed alone.
ER4045 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 |
|---|---|---|
| Siprincipal alloying element, lowers melting range | 9 – 11 | 10 |
| Fe | ≤ 0.8 | 0.4 |
| Cu | ≤ 0.3 | 0.05 |
| Mn | ≤ 0.05 | 0.01 |
| Mgkept low for controlled-atmosphere (NOCOLOK) brazing | ≤ 0.05 | 0.01 |
| Zn | ≤ 0.1 | 0.02 |
| Others (each) | ≤ 0.05 | |
| Others (total) | ≤ 0.15 | |
| Al | balance |
What surface finishes work on ER4045?
Anodizes dark and blotchy due to silicon; chemical etching darkens the deposit — prefer paint, chromate/Ti-Zr conversion coat or leave as-brazed.
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 ER4045 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- AWS A5.10 ER4045
- EN / DIN / Werkstoff-Nr.
- S Al 4045
- Other
- 4045
- Similar grades
- SAlSi-3
How much does ER4045 cost?
ER4045 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.
ER4045 — frequently asked
What is ER4045 used for?
ER4045 is typically used for brazing sheet cladding, heat exchanger fabrication and TIG welding of thin sheet. In short: lowest-melting Al-Si filler; brazing sheet cladding alloy; made for capillary brazing.
What is the yield strength of ER4045?
ER4045 has a typical yield strength of 60 MPa (8.7 ksi) and a tensile strength of 165 MPa (23.9 ksi) — weaker than 93% of aluminum grades. Strength varies by condition: see the 5 listed tempers.
Is ER4045 easy to machine?
Not especially — machinability is rated fair (42/100, worse than 77% of aluminum grades). Rarely machined; the ~10% Si makes it abrasive — use PCD or polished carbide, high speed, low feed, generous coolant.
Can ER4045 be welded?
Yes — weldability is rated excellent (92/100). Excellent as a filler for 3000/6000 series and cast Al-Si; use AC-TIG or pulsed MIG, keep heat input low, never for 5000 series with >2.5% Mg (brittle Mg2Si) or for parts to be anodized cosmetically.
What surface finishes work on ER4045?
Anodizes dark and blotchy due to silicon; chemical etching darkens the deposit — prefer paint, chromate/Ti-Zr conversion coat or leave as-brazed.
Can ER4045 be formed, bent or molded?
Very fluid on melting (near-eutectic), ideal for capillary brazing gaps of 0.05–0.15 mm; as strip it is roll-clad onto 3003/3000-series core rather than formed alone.
What is the maximum service temperature of ER4045?
ER4045 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 ER4045-AW and ER4045-H18?
AW is the default condition — default condition: properties of the ER4045 deposit as laid down by TIG/MIG on aluminium base metal. H18: full-hard thin foil/shim stock for flat brazing preforms that are stamped, not formed. Yield strength is 60 MPa in AW versus 170 MPa in H18.
How much does ER4045 cost?
ER4045 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
- AWS A5.10/A5.10M — Bare Aluminum and Aluminum-Alloy Welding Electrodes and Rods — AWS (2021)
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering (Aluminum brazing sheet) — ASM International (1993)
- Aluminium brazing sheet / 4045 clad alloy datasheets — Novelis / Granges (2022)
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.