Aluminum 1188-H22
Temper
AA 1188 · UNS A91188 · EN Al99.88
H22 = strain hardened and partially annealed, quarter hard
Back-annealed quarter-hard temper: H12-level strength with better ductility for forming.
Values for the H22 condition
Other 1188 tempers and conditions
1188 is listed in 12 conditions; see the grade overview at 1188.
Compare all 12 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ODefault Annealed | Pick for maximum formability, conductivity and corrosion resistance — deep drawing, linings, foil stock, reflectors. | 22 | 62 | 45 | 17 HB | 62.5 % IACS |
Slightly strain hardened | Near-O softness with the light work introduced by levelling; common on plate and extruded sections. | 28 | 68 | 38 | 19 HB | 62.3 % IACS |
As fabricated | Hot-worked or extruded stock with no mechanical property limits; use where the part will be annealed or formed afterwards. | 30 | 70 | 32 | 19 HB | 62 % IACS |
H22This page Strain hardened and partially annealed, quarter hard | Back-annealed quarter-hard temper: H12-level strength with better ductility for forming. | 52 | 78 | 24 | 22 HB | 62.2 % IACS |
Strain hardened, quarter hard | Light cold work for slightly stiffer sheet that still forms and bends well. | 58 | 78 | 20 | 22 HB | 62 % IACS |
Strain hardened and partially annealed, half hard | Half-hard sheet with restored bend ductility — the usual choice for formed panels and linings. | 66 | 90 | 16 | 26 HB | 62 % IACS |
Strain hardened, half hard | The usual compromise temper for flat sheet that must hold shape yet still be bent. | 72 | 90 | 12 | 26 HB | 62 % IACS |
Strain hardened and partially annealed, three-quarter hard | Three-quarter hard with partial anneal for strip that must still take a tight roll-form. | 80 | 103 | 10 | 30 HB | 61.8 % IACS |
Strain hardened, three-quarter hard | Higher-strength strip where only mild forming (roll forming, gentle bends) is required. | 88 | 103 | 8 | 30 HB | 61.8 % IACS |
Strain hardened and partially annealed, full hard | Full-hard stabilised strip where slightly better ductility than H18 is needed at similar strength. | 98 | 118 | 6 | 33 HB | 61.5 % IACS |
Strain hardened, full hard | Full-hard strip and foil: highest practical strength for this purity, minimal formability. | 105 | 118 | 5 | 33 HB | 61.5 % IACS |
Strain hardened, extra hard | Extra-hard rolling used mainly for thin capacitor/electrode foil where stiffness and handling strength matter. | 118 | 132 | 3 | 36 HB | 61.3 % IACS |
What is 1188-H22?
1188-H22 is 1188 in the H22 temper — back-annealed quarter-hard temper: H12-level strength with better ductility for forming. 1188-H22 has a yield strength of 52 MPa (7.54 ksi) and a tensile strength of 78 MPa (11.3 ksi) — weaker than 95% of aluminum grades. Elongation at break is 24% and the elastic modulus is 69 GPa (10 Msi). 1188-H22 has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 657°C (1,215 °F). O is the default condition FabDigit quotes; H22 is available on request or by drawing note.
Advantages
- Conducts heat well — 233 W/m·K (134.6 BTU/hr·ft·°F), better than 99% of aluminum grades
- High electrical conductivity — 62.2 % IACS, better than 99% of aluminum grades
- Polishes to a fine finish — 90/100, better than 98% of aluminum grades
- Good corrosion resistance — 78/100, better than 94% of aluminum grades
- Forms and bends easily — 90/100, better than 93% of aluminum grades
Limitations
- Difficult to machine — 22/100, worse than 98% of aluminum grades
- Low strength — 52 MPa (7.54 ksi), worse than 95% of aluminum grades
1188-H22 properties
Typical room-temperature values for 1188-H22; 18 are specific to this condition. Other listed values are 1188 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
1188-H22 has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 657°C (1,215 °F).
Mechanical10
1188-H22 has a yield strength of 52 MPa (7.54 ksi) and a tensile strength of 78 MPa (11.3 ksi) — weaker than 95% of aluminum grades. Elongation at break is 24% and the elastic modulus is 69 GPa (10 Msi).
Thermal6
1188-H22 is rated for continuous service to 130°C (266 °F). It conducts heat at 233 W/m·K (134.6 BTU/hr·ft·°F), better than 99% of aluminum grades. Thermal expansion is 23.6 µm/m·K (13.1 µin/in·°F).
Electrical3
1188-H22 conducts electricity at 62.2 % IACS, better than 99% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is very good (78/100), better than 94% of aluminum grades.
Sustainability4
Producing a kilogram of 1188-H22 takes about 215 MJ of energy and emits 13.5 kg of CO₂ — more than 93% of aluminum grades. Typical recycled content is 0%.
Manufacturability8
1188-H22's machinability is poor (22/100, worse than 98% of aluminum grades); weldability excellent (90/100); formability excellent (90/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1188-H22
Is 1188 easy to machine?
Very soft and gummy — use polished high-rake carbide, high speed, flood coolant or mist and generous chip clearance to avoid built-up edge; cold-worked H1x tempers cut noticeably cleaner than O.
Can 1188 be welded?
Excellent by TIG/MIG and resistance welding with 1100 or matching 1188 filler; the weld and HAZ revert to O-temper strength, so design joints for annealed properties.
Can 1188 be formed, bent or molded?
Outstanding cold formability in O/H111 — deep drawing, spinning, tight bends and rolling down to thin foil; springback is minimal but the surface marks easily.
What surface finishes work on 1188?
Ideal for bright and clear anodising and chemical/electro-brightening thanks to the low Fe/Si; polishes to a high specular reflectance, and takes conversion coatings and paint after standard alkaline etch/desmut.
1188 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 |
|---|---|---|
| Si | ≤ 0.06 | 0.03 |
| Fe | ≤ 0.06 | 0.04 |
| Cukept very low for corrosion resistance | ≤ 0.01 | 0 |
| Mn | ≤ 0.01 | — |
| Mg | ≤ 0.01 | — |
| Zn | ≤ 0.03 | — |
| Ti | ≤ 0.01 | — |
| VV+Ti often limited jointly | ≤ 0.05 | — |
| Ga | ≤ 0.03 | — |
| Others (each) | ≤ 0.01 | — |
| Al99.88 % Al minimum by difference | ≥ 99.88 (balance) | — |
1188-H22 — frequently asked
What is 1188-H22 used for?
1188-H22 is typically used for electrolytic capacitor foil, high-purity chemical processing equipment, reflectors and specialty electrical conductors. In short: highest-purity 1000-series stock; best bright-anodizing aluminum; 62.5% IACS conductivity.
What is the yield strength of 1188-H22?
1188-H22 has a typical yield strength of 52 MPa (7.54 ksi) and a tensile strength of 78 MPa (11.3 ksi) — weaker than 95% of aluminum grades. Strength varies by condition: see the 12 listed tempers.
Is 1188-H22 easy to machine?
Not especially — machinability is rated poor (22/100, worse than 98% of aluminum grades). Very soft and gummy — use polished high-rake carbide, high speed, flood coolant or mist and generous chip clearance to avoid built-up edge; cold-worked H1x tempers cut noticeably cleaner than O.
Can 1188-H22 be welded?
Yes — weldability is rated excellent (90/100). Excellent by TIG/MIG and resistance welding with 1100 or matching 1188 filler; the weld and HAZ revert to O-temper strength, so design joints for annealed properties.
What surface finishes work on 1188-H22?
Ideal for bright and clear anodising and chemical/electro-brightening thanks to the low Fe/Si; polishes to a high specular reflectance, and takes conversion coatings and paint after standard alkaline etch/desmut.
Can 1188-H22 be formed, bent or molded?
Outstanding cold formability in O/H111 — deep drawing, spinning, tight bends and rolling down to thin foil; springback is minimal but the surface marks easily.
What is the maximum service temperature of 1188-H22?
1188-H22 is rated for continuous use to about 130°C (266 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1188-O and 1188-H19?
O is the default condition — pick for maximum formability, conductivity and corrosion resistance — deep drawing, linings, foil stock, reflectors. H19: extra-hard rolling used mainly for thin capacitor/electrode foil where stiffness and handling strength matter. Yield strength is 22 MPa in O versus 118 MPa in H19.
Sources
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum and Wrought Aluminum Alloys (Teal Sheets) — The Aluminum Association (2018)
- ASTM B209 / B209M — Aluminum and Aluminum-Alloy Sheet and Plate — ASTM International (2021)
- 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.