Aluminum 3B21-H19
Temper
GB 3B21
H19 = strain hardened, extra hard
Only for thin strip and foil where maximum as-rolled hardness is wanted; essentially non-formable.
Values for the H19 condition
Other 3B21 tempers and conditions
3B21 is listed in 16 conditions; see the grade overview at 3B21.
Compare all 16 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Pick for deep drawing, spinning, tight bends and any severe cold forming. | 52 | 130 | 26 | 30 HB | 42 % IACS |
Strain hardened from hot working only | Standard temper for thicker hot-rolled plate that will be welded or machined rather than cold formed. | 65 | 145 | 18 | 33 HB | 42 % IACS |
As fabricated | Mill-supplied hot-worked/extruded stock with no guaranteed mechanicals; buy only if you will heat treat, form or test yourself. | 65 | 140 | 18 | 30 HB | 42 % IACS |
Strain hardened and partially annealed, quarter hard | Same strength class as H12 but with restored ductility — use for tube bending and formed profiles. | 115 | 150 | 15 | 37 HB | 41 % IACS |
Strain hardened and stabilized, quarter hard | Stabilized temper (thermal treatment after rolling) for the Mg-bearing chemistry; use when long-term property stability matters. | 120 | 155 | 14 | 38 HB | 41 % IACS |
Strain hardened, quarter hard | Light work hardening when a little extra stiffness is needed but bending is still frequent. | 125 | 155 | 12 | 38 HB | 41 % IACS |
Strain hardened and partially annealed, half hard | Most common temper for formed architectural sheet and roll-formed panels needing H14 strength with better bend behaviour. | 140 | 170 | 10 | 43 HB | 40 % IACS |
Strain hardened and stabilized, half hard | Stabilized mid-strength sheet/plate for welded tanks and vessels held at mildly elevated temperature. | 145 | 175 | 10 | 44 HB | 40 % IACS |
H14Default Strain hardened, half hard | The default stocked sheet/coil temper: best balance of panel stiffness and roll-forming/bending ability. | 150 | 175 | 8 | 44 HB | 40 % IACS |
Strain hardened and partially annealed, three-quarter hard | High-strength strip that must still take a modest bend, e.g. clip and bracket stampings. | 165 | 195 | 6 | 49 HB | 40 % IACS |
Strain hardened and stabilized, three-quarter hard | Stabilized high-strength strip for lightly formed, dimensionally stable parts. | 170 | 200 | 6 | 50 HB | 40 % IACS |
Strain hardened, three-quarter hard | Use where flat strength and dent resistance dominate and only mild forming is required. | 175 | 200 | 5 | 50 HB | 40 % IACS |
Strain hardened and partially annealed, full hard | Full-hard strip with slightly better ductility than H18; niche stamping/spring-clip use. | 190 | 220 | 4 | 55 HB | 39.5 % IACS |
Strain hardened and stabilized, full hard | Highest stabilized strength; flat parts only, essentially no forming reserve. | 195 | 225 | 4 | 56 HB | 39.5 % IACS |
Strain hardened, full hard | Maximum strain-hardened strength for flat parts, shims and stamped blanks; bending must be generous-radius. | 200 | 225 | 4 | 56 HB | 40 % IACS |
H19This page Strain hardened, extra hard | Only for thin strip and foil where maximum as-rolled hardness is wanted; essentially non-formable. | 220 | 245 | 2 | 60 HB | 39 % IACS |
What is 3B21-H19?
3B21-H19 is 3B21 in the H19 temper — only for thin strip and foil where maximum as-rolled hardness is wanted; essentially non-formable. 3B21-H19 has a yield strength of 220 MPa (31.9 ksi) and a tensile strength of 245 MPa (35.5 ksi) — stronger than 59% of aluminum grades. Elongation at break is 2% and the elastic modulus is 69 GPa (10 Msi). 3B21-H19 has a density of 2.73 g/cm³ (0.0986 lb/in³), heavier than 61% of aluminum grades. It melts at 643°C (1,189 °F). H14 is the default condition FabDigit quotes; H19 is available on request or by drawing note.
Advantages
- Good corrosion resistance — 68/100, better than 75% of aluminum grades
Limitations
- Limited ductility — 2%, worse than 87% of aluminum grades
- Difficult to machine — 40/100, worse than 81% of aluminum grades
- Limited service temperature — 120°C (248 °F), worse than 79% of aluminum grades
3B21-H19 properties
Typical room-temperature values for 3B21-H19; 18 are specific to this condition. Other listed values are 3B21 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
3B21-H19 has a density of 2.73 g/cm³ (0.0986 lb/in³), heavier than 61% of aluminum grades. It melts at 643°C (1,189 °F).
Mechanical10
3B21-H19 has a yield strength of 220 MPa (31.9 ksi) and a tensile strength of 245 MPa (35.5 ksi) — stronger than 59% of aluminum grades. Elongation at break is 2% and the elastic modulus is 69 GPa (10 Msi).
Thermal6
3B21-H19 is rated for continuous service to 120°C (248 °F). It conducts heat at 155 W/m·K (89.6 BTU/hr·ft·°F), better than 71% of aluminum grades. Thermal expansion is 23.2 µm/m·K (12.9 µin/in·°F).
Electrical3
3B21-H19 conducts electricity at 39 % IACS, better than 65% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (68/100), better than 75% of aluminum grades.
Sustainability4
Producing a kilogram of 3B21-H19 takes about 200 MJ of energy and emits 12.5 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 35%.
Manufacturability7
3B21-H19's machinability is fair (40/100, worse than 81% of aluminum grades); weldability very good (80/100); formability fair (35/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 3B21-H19
Is 3B21 easy to machine?
Soft and gummy: use sharp polished high-rake carbide, high speed, low feed and flood coolant/lubricant to avoid built-up edge; harder H16–H18 tempers give cleaner chips.
Can 3B21 be welded?
Excellent with GTAW/GMAW using ER4043 or ER5356 filler, and readily resistance-spot welded; the HAZ reverts toward O temper, so design joints for annealed strength.
Can 3B21 be formed, bent or molded?
Very good cold formability — O/H22/H24 tempers deep draw, roll-form and bend tightly; interstage anneal at 340–400 °C if severe multi-stage drawing is needed.
What surface finishes work on 3B21?
Takes clear/protective sulphuric anodize, chromate/chrome-free conversion coating, and coil paint/PVDF well; bright decorative anodizing is only fair because Mn dispersoids grey the film.
3B21 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; Si+Fe often jointly capped | ≤ 0.5 | 0.2 |
| Feimpurity limit | ≤ 0.5 | 0.3 |
| Cukept low for corrosion resistance | ≤ 0.1 | 0.03 |
| Mnprincipal strengthening/dispersoid element | 1 – 1.6 | 1.3 |
| Mgsmall deliberate addition — main difference vs 3A21 | 0.1 – 0.6 | 0.35 |
| Zn | ≤ 0.1 | — |
| Tigrain refiner residual | ≤ 0.15 | 0.03 |
| Others (each)total others ≤ 0.15 | ≤ 0.05 | — |
| Alremainder; confirm exact limits against the current GB/T 3190 edition and the mill certificate | balance | — |
3B21-H19 — frequently asked
What is 3B21-H19 used for?
3B21-H19 is typically used for architectural cladding, roofing and gutter sheet, general fabrication plate and corrosion-resistant panels. In short: stronger than 3A21 sheet; formable architectural alloy; weldable, non-heat-treatable.
What is the yield strength of 3B21-H19?
3B21-H19 has a typical yield strength of 220 MPa (31.9 ksi) and a tensile strength of 245 MPa (35.5 ksi) — stronger than 59% of aluminum grades. Strength varies by condition: see the 16 listed tempers.
Is 3B21-H19 easy to machine?
Not especially — machinability is rated fair (40/100, worse than 81% of aluminum grades). Soft and gummy: use sharp polished high-rake carbide, high speed, low feed and flood coolant/lubricant to avoid built-up edge; harder H16–H18 tempers give cleaner chips.
Can 3B21-H19 be welded?
Yes — weldability is rated very good (80/100). Excellent with GTAW/GMAW using ER4043 or ER5356 filler, and readily resistance-spot welded; the HAZ reverts toward O temper, so design joints for annealed strength.
What surface finishes work on 3B21-H19?
Takes clear/protective sulphuric anodize, chromate/chrome-free conversion coating, and coil paint/PVDF well; bright decorative anodizing is only fair because Mn dispersoids grey the film.
Can 3B21-H19 be formed, bent or molded?
Very good cold formability — O/H22/H24 tempers deep draw, roll-form and bend tightly; interstage anneal at 340–400 °C if severe multi-stage drawing is needed.
What is the maximum service temperature of 3B21-H19?
3B21-H19 is rated for continuous use to about 120°C (248 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 3B21-H14 and 3B21-O?
H14 is the default condition — the default stocked sheet/coil temper: best balance of panel stiffness and roll-forming/bending ability. O: pick for deep drawing, spinning, tight bends and any severe cold forming. Yield strength is 150 MPa in H14 versus 52 MPa in O.
Sources
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys (3000 series Al-Mn data) — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: Materials (aluminium alloys) — ASM International (2005)
- Aluminum Association Teal Sheets — Alloy and Temper Designations — The Aluminum Association (2018)
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.