Aluminum 1275-H28
Supply condition
AA 1275 · EN AW-1275, Al99.75
H28 = strain hardened and partially annealed, full hard
Full-hard strip stabilized by a partial anneal; used for foil and thin strip needing consistent hardness.
Values for the H28 condition
Other 1275 tempers and conditions
1275 is listed in 13 conditions; see the grade overview at 1275.
Compare all 13 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Pick for deep drawing, spinning, chemical-vessel lining and foil where maximum ductility matters. | 25 | 70 | 42 | 19 HB | 62 % IACS |
Slightly strain hardened | Sheet/plate essentially in O condition but with incidental work from levelling or stretching. | 30 | 75 | 35 | 21 HB | 61.8 % IACS |
Strain hardened from hot working only | Hot-rolled plate, extrusions and forged shapes where only modest guaranteed strength is required. | 32 | 78 | 28 | 22 HB | 61.5 % IACS |
As fabricated | Extruded or cast-and-rolled stock supplied without guaranteed mechanicals; used where properties are set by later processing. | 35 | 80 | 25 | 23 HB | 61.5 % IACS |
Strain hardened and partially annealed, quarter hard | Same strength class as H12 but with better ductility and more stable properties for forming. | 68 | 88 | 16 | 25 HB | 61.8 % IACS |
Strain hardened, quarter hard | Light cold work for slightly higher strength while retaining good bending and forming. | 72 | 85 | 14 | 25 HB | 61.8 % IACS |
Strain hardened and partially annealed, half hard | Preferred over H14 when the part must still be bent or drawn after supply. | 85 | 103 | 11 | 30 HB | 61.5 % IACS |
H14Default Strain hardened, half hard | The general-purpose stocked sheet temper: usable strength and flatness with acceptable bending. | 90 | 100 | 8 | 30 HB | 61.5 % IACS |
Strain hardened and partially annealed, three-quarter hard | H16-level strength with improved bend behaviour, for roll-formed profiles and trim. | 100 | 118 | 7 | 34 HB | 61.3 % IACS |
Strain hardened, three-quarter hard | Choose for flat panels and shallow forming where higher stiffness under handling is wanted. | 105 | 115 | 5 | 34 HB | 61.3 % IACS |
H28This page Strain hardened and partially annealed, full hard | Full-hard strip stabilized by a partial anneal; used for foil and thin strip needing consistent hardness. | 118 | 132 | 5 | 38 HB | 61 % IACS |
Strain hardened, full hard | Maximum practical strength from cold work; for flat strip, foil stock and rigid trim with minimal forming. | 120 | 130 | 4 | 38 HB | 61 % IACS |
Strain hardened, extra hard | Extra-hard strip/wire condition beyond H18, used for springy strip, foil and conductor wire. | 140 | 150 | 3 | 42 HB | 60.8 % IACS |
What is 1275-H28?
1275-H28 is 1275 supplied in the H28 condition — full-hard strip stabilized by a partial anneal; used for foil and thin strip needing consistent hardness. 1275-H28 has a yield strength of 118 MPa (17.1 ksi) and a tensile strength of 132 MPa (19.1 ksi) — weaker than 78% of aluminum grades. Elongation at break is 5% and the elastic modulus is 69 GPa (10 Msi). 1275-H28 has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 646°C (1,195 °F). H14 is the default condition FabDigit quotes; H28 is available on request or by drawing note.
Advantages
- High electrical conductivity — 61 % IACS, better than 96% of aluminum grades
- Polishes to a fine finish — 85/100, better than 96% of aluminum grades
- Conducts heat well — 228 W/m·K (131.7 BTU/hr·ft·°F), better than 95% of aluminum grades
- Readily welded — 89/100, better than 87% of aluminum grades
Limitations
- Limited service temperature — 110°C (230 °F), worse than 89% of aluminum grades
- Difficult to machine — 36/100, worse than 84% of aluminum grades
- Low strength — 118 MPa (17.1 ksi), worse than 78% of aluminum grades
1275-H28 properties
Typical room-temperature values for 1275-H28; 17 are specific to this condition. Other listed values are 1275 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
1275-H28 has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 646°C (1,195 °F).
Mechanical11
1275-H28 has a yield strength of 118 MPa (17.1 ksi) and a tensile strength of 132 MPa (19.1 ksi) — weaker than 78% of aluminum grades. Elongation at break is 5% and the elastic modulus is 69 GPa (10 Msi).
Thermal6
1275-H28 is rated for continuous service to 110°C (230 °F). It conducts heat at 228 W/m·K (131.7 BTU/hr·ft·°F), better than 95% of aluminum grades. Thermal expansion is 23.6 µm/m·K (13.1 µin/in·°F).
Electrical3
1275-H28 conducts electricity at 61 % IACS, better than 96% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (61/100), better than 64% of aluminum grades.
Sustainability4
Producing a kilogram of 1275-H28 takes about 210 MJ of energy and emits 13 kg of CO₂ — more than 88% of aluminum grades. Typical recycled content is 3%.
Manufacturability7
1275-H28's machinability is fair (36/100, worse than 84% of aluminum grades); weldability excellent (89/100); formability fair (50/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1275-H28
Is 1275 easy to machine?
Very soft and gummy — use polished high-rake carbide, high speed, generous feed and flood coolant or lubricated air to avoid built-up edge and smeared surfaces.
Can 1275 be welded?
Excellent GTAW/GMAW and resistance weldability; use 1100 or 1188 filler for matching purity and expect the weld/HAZ to return to O-temper strength.
Can 1275 be formed, bent or molded?
Outstanding cold formability in O/H22 — deep drawing, spinning and roll forming are easy; interanneal at 340–410 °C when heavy work-hardening builds up.
What surface finishes work on 1275?
Ideal for bright dipping and clear or coloured anodizing with very low haze; chemical conversion coating, painting and electropolishing all work well, but pure Al is soft so surfaces mark easily.
1275 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 | ≤ 0.08 | 0.04 |
| Feimpurity limit | ≤ 0.12 | 0.07 |
| Cu | ≤ 0.05 | 0.01 |
| Mn | ≤ 0.02 | 0.01 |
| Mg | ≤ 0.02 | 0.01 |
| Zn | ≤ 0.05 | 0.01 |
| Ti | ≤ 0.03 | 0.01 |
| V | ≤ 0.05 | 0.01 |
| Ga | ≤ 0.03 | 0.01 |
| Others (each)each other element | ≤ 0.02 | — |
| Al99.75 % min by difference | ≥ 99.75 (balance) | — |
1275-H28 — frequently asked
What is 1275-H28 used for?
1275-H28 is typically used for chemical process vessels, decorative trim, electrical conductor stock and reflector sheet. In short: european 99.75% purity grade; high conductivity, 61.5% IACS; low ductility as supplied.
What is the yield strength of 1275-H28?
1275-H28 has a typical yield strength of 118 MPa (17.1 ksi) and a tensile strength of 132 MPa (19.1 ksi) — weaker than 78% of aluminum grades. Strength varies by condition: see the 13 listed tempers.
Is 1275-H28 easy to machine?
Not especially — machinability is rated fair (36/100, worse than 84% of aluminum grades). Very soft and gummy — use polished high-rake carbide, high speed, generous feed and flood coolant or lubricated air to avoid built-up edge and smeared surfaces.
Can 1275-H28 be welded?
Yes — weldability is rated excellent (89/100). Excellent GTAW/GMAW and resistance weldability; use 1100 or 1188 filler for matching purity and expect the weld/HAZ to return to O-temper strength.
What surface finishes work on 1275-H28?
Ideal for bright dipping and clear or coloured anodizing with very low haze; chemical conversion coating, painting and electropolishing all work well, but pure Al is soft so surfaces mark easily.
Can 1275-H28 be formed, bent or molded?
Outstanding cold formability in O/H22 — deep drawing, spinning and roll forming are easy; interanneal at 340–410 °C when heavy work-hardening builds up.
What is the maximum service temperature of 1275-H28?
1275-H28 is rated for continuous use to about 110°C (230 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1275-H14 and 1275-O?
H14 is the default condition — the general-purpose stocked sheet temper: usable strength and flatness with acceptable bending. O: pick for deep drawing, spinning, chemical-vessel lining and foil where maximum ductility matters. Yield strength is 90 MPa in H14 versus 25 MPa in O.
Sources
- EN 573-3 Aluminium and aluminium alloys — Chemical composition of wrought products — CEN (2019)
- EN 485-2 Aluminium and aluminium alloys — Sheet, strip and plate: Mechanical properties — CEN (2016)
- 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 and Special-Purpose Materials — ASM International (1990)
- ASM Handbook Vol. 13B — Corrosion: Materials — ASM International (2005)
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.