Aluminum 4115-H18
Temper
AA 4115 · EN AW-4115, AlSi2MnMgCu
H18 = strain hardened, full hard
Maximum pre-braze strength and stiffness; use for thin fin stock or where sagging resistance during the braze cycle matters.
Values for the H18 condition
Other 4115 tempers and conditions
4115 is listed in 6 conditions; see the grade overview at 4115.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ODefault Annealed | Choose for deep-drawn or heavily formed brazing-sheet parts (tubes, header plates) where maximum formability before the braze cycle is needed. | 55 | 130 | 25 | 38 HB | 44 % IACS |
Strain hardened, quarter hard | Light cold work for slightly stiffer sheet that still bends and draws easily before brazing. | 130 | 160 | 10 | 45 HB | 43 % IACS |
Strain hardened, half hard | The usual as-supplied condition for stamped heat-exchanger plates and fin/tube stock — good stiffness with workable ductility. | 155 | 180 | 8 | 50 HB | 43 % IACS |
Strain hardened and partially annealed, three-quarter hard | Stabilised/partially annealed route to near-H16 strength with better ductility and flatness for formed brazing-sheet components. | 165 | 195 | 7 | 54 HB | 43 % IACS |
Strain hardened, three-quarter hard | Higher-strength coil for roll-formed tube and fin where only gentle bending is required. | 180 | 200 | 5 | 56 HB | 42 % IACS |
H18This page Strain hardened, full hard | Maximum pre-braze strength and stiffness; use for thin fin stock or where sagging resistance during the braze cycle matters. | 205 | 225 | 4 | 62 HB | 42 % IACS |
What is 4115-H18?
4115-H18 is 4115 in the H18 temper — maximum pre-braze strength and stiffness; use for thin fin stock or where sagging resistance during the braze cycle matters. 4115-H18 has a yield strength of 205 MPa (29.7 ksi) and a tensile strength of 225 MPa (32.6 ksi) — stronger than 54% of aluminum grades. Elongation at break is 4% and the elastic modulus is 70 GPa (10.2 Msi). 4115-H18 has a density of 2.71 g/cm³ (0.0979 lb/in³), heavier than 51% of aluminum grades. It melts at 600°C (1,112 °F). O is the default condition FabDigit quotes; H18 is available on request or by drawing note.
Advantages
- High electrical conductivity — 42 % IACS, better than 81% of aluminum grades
- Conducts heat well — 166 W/m·K (95.9 BTU/hr·ft·°F), better than 80% of aluminum grades
Limitations
- Limited service temperature — 100°C (212 °F), worse than 91% of aluminum grades
- Hard to polish — 40/100, worse than 91% of aluminum grades
4115-H18 properties
Typical room-temperature values for 4115-H18; 14 are specific to this condition. Other listed values are 4115 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
4115-H18 has a density of 2.71 g/cm³ (0.0979 lb/in³), heavier than 51% of aluminum grades. It melts at 600°C (1,112 °F).
Mechanical11
4115-H18 has a yield strength of 205 MPa (29.7 ksi) and a tensile strength of 225 MPa (32.6 ksi) — stronger than 54% of aluminum grades. Elongation at break is 4% and the elastic modulus is 70 GPa (10.2 Msi).
Thermal6
4115-H18 is rated for continuous service to 100°C (212 °F). It conducts heat at 166 W/m·K (95.9 BTU/hr·ft·°F), better than 80% of aluminum grades. Thermal expansion is 22.3 µm/m·K (12.4 µin/in·°F).
Electrical3
4115-H18 conducts electricity at 42 % IACS, better than 81% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (47/100), worse than 59% of aluminum grades.
Sustainability4
Producing a kilogram of 4115-H18 takes about 200 MJ of energy and emits 12 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 30%.
Manufacturability8
4115-H18's machinability is fair (52/100, worse than 63% of aluminum grades); weldability good (55/100); formability poor (30/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 4115-H18
Is 4115 easy to machine?
Machines like a soft Al-Mn sheet but the Si particles are abrasive — use PCD or polished-flute carbide, high speed, low feed and flood coolant to avoid built-up edge in O temper.
Can 4115 be welded?
GTAW/GMAW with 4043 filler is possible on bare core, but the ~600 °C solidus and clad braze layers mean joining is normally done by CAB (NOCOLOK) brazing rather than fusion welding.
Can 4115 be formed, bent or molded?
Excellent cold formability in O/H12; stamped and roll-formed as brazing sheet, with H14–H18 reserved for shallow forming and sag resistance during the braze cycle.
What surface finishes work on 4115?
Anodizes grey/dull because of Si; for service protection rely on the sacrificial clad layer, Zn-arc spray, chromate-free conversion coating or e-coat rather than decorative anodising or polishing.
4115 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 addition, Al-Si2 core | 1.5 – 2.5 | 2 |
| Feimpurity limit | ≤ 0.6 | 0.3 |
| Cupost-braze age hardening | 0.1 – 0.6 | 0.3 |
| Mndispersoid strengthening / grain control | 0.5 – 1.2 | 0.9 |
| Mglimited for controlled-atmosphere (NOCOLOK) brazing | 0.05 – 0.5 | 0.2 |
| Zn | ≤ 0.25 | — |
| Tigrain refiner | ≤ 0.15 | — |
| Others (each)others total 0.15 max | ≤ 0.05 | — |
| Alremainder; verify exact limits against current AA Teal Sheet / EN 573-3 registration | balance | — |
4115-H18 — frequently asked
What is 4115-H18 used for?
4115-H18 is typically used for high-strength brazing sheet core, automotive heat exchanger tanks and headers, radiator and condenser tube plate, charge-air cooler side plates and stamped and roll-formed brazing sheet components. In short: strongest brazing-sheet core; sag-resistant during brazing; cu lowers corrosion resistance.
What is the yield strength of 4115-H18?
4115-H18 has a typical yield strength of 205 MPa (29.7 ksi) and a tensile strength of 225 MPa (32.6 ksi) — stronger than 54% of aluminum grades. Strength varies by condition: see the 6 listed tempers.
Is 4115-H18 easy to machine?
Reasonably — machinability is rated fair (52/100, worse than 63% of aluminum grades). Machines like a soft Al-Mn sheet but the Si particles are abrasive — use PCD or polished-flute carbide, high speed, low feed and flood coolant to avoid built-up edge in O temper.
Can 4115-H18 be welded?
Yes — weldability is rated good (55/100). GTAW/GMAW with 4043 filler is possible on bare core, but the ~600 °C solidus and clad braze layers mean joining is normally done by CAB (NOCOLOK) brazing rather than fusion welding.
What surface finishes work on 4115-H18?
Anodizes grey/dull because of Si; for service protection rely on the sacrificial clad layer, Zn-arc spray, chromate-free conversion coating or e-coat rather than decorative anodising or polishing.
Can 4115-H18 be formed, bent or molded?
Excellent cold formability in O/H12; stamped and roll-formed as brazing sheet, with H14–H18 reserved for shallow forming and sag resistance during the braze cycle.
What is the maximum service temperature of 4115-H18?
4115-H18 is rated for continuous use to about 100°C (212 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 4115-O and 4115-H18?
O is the default condition — choose for deep-drawn or heavily formed brazing-sheet parts (tubes, header plates) where maximum formability before the braze cycle is needed. H18: maximum pre-braze strength and stiffness; use for thin fin stock or where sagging resistance during the braze cycle matters. Yield strength is 55 MPa in O versus 205 MPa in H18.
Sources
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
- EN 573-3 Aluminium and aluminium alloys — Chemical composition of wrought products — CEN (2019)
- EN 485-2 Aluminium sheet, strip and plate — Mechanical properties — CEN (2016)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol.6 — Welding, Brazing and Soldering (aluminium brazing sheet) — ASM International (1993)
- Aluminium brazing sheet core alloy data (heat-exchanger products) — Novelis / Constellium / Granges (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.