Aluminum 3303-H18
Temper
AA 3303 · UNS A93303
H18 = strain hardened, full hard
Maximum as-drawn strength and best chip control; almost no remaining bend ductility.
Values for the H18 condition
Other 3303 tempers and conditions
3303 is listed in 7 conditions; see the grade overview at 3303.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ODefault Annealed | Pick for maximum ductility in drawn tube that will be bent, expanded, flared or brazed after forming. | 42 | 110 | 33 | 28 HB | 50 % IACS |
Strain hardened from hot working only | Extruded tube or shape supplied as-fabricated with guaranteed minimum properties. | 55 | 115 | 25 | 30 HB | 49 % IACS |
Strain hardened, quarter hard | Light cold work for slightly stiffer tube that still bends easily. | 125 | 130 | 12 | 35 HB | 42 % IACS |
Strain hardened, half hard | Most common work-hardened temper: good balance of strength, formability and cleaner machining. | 145 | 150 | 9 | 40 HB | 41 % IACS |
Strain hardened then partially annealed | Drawn-tube temper giving near-H16 strength with recovered ductility for bending. | 160 | 179 | 8 | 46 HB | 41 % IACS |
Strain hardened, three-quarter hard | Use where higher hoop strength is needed and only mild forming follows. | 170 | 180 | 5 | 47 HB | 41 % IACS |
H18This page Strain hardened, full hard | Maximum as-drawn strength and best chip control; almost no remaining bend ductility. | 185 | 200 | 4 | 55 HB | 40 % IACS |
What is 3303-H18?
3303-H18 is 3303 in the H18 temper — maximum as-drawn strength and best chip control; almost no remaining bend ductility. 3303-H18 has a yield strength of 185 MPa (26.8 ksi) and a tensile strength of 200 MPa (29 ksi) — weaker than 53% of aluminum grades. Elongation at break is 4% and the elastic modulus is 69 GPa (10 Msi). 3303-H18 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). O is the default condition FabDigit quotes; H18 is available on request or by drawing note.
Advantages
- High service temperature — 200°C (392 °F), better than 90% of aluminum grades
- Good corrosion resistance — 70/100, better than 79% of aluminum grades
3303-H18 properties
Typical room-temperature values for 3303-H18; 14 are specific to this condition. Other listed values are 3303 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
3303-H18 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
3303-H18 has a yield strength of 185 MPa (26.8 ksi) and a tensile strength of 200 MPa (29 ksi) — weaker than 53% of aluminum grades. Elongation at break is 4% and the elastic modulus is 69 GPa (10 Msi).
Thermal6
3303-H18 is rated for continuous service to 200°C (392 °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
3303-H18 conducts electricity at 40 % IACS, better than 72% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is very good (70/100), better than 79% of aluminum grades.
Sustainability4
Producing a kilogram of 3303-H18 takes about 200 MJ of energy and emits 12.5 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 40%.
Manufacturability7
3303-H18's machinability is fair (45/100, worse than 72% 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 3303-H18
Is 3303 easy to machine?
Gummy in O temper — use sharp polished high-rake carbide, high speed and flood emulsion; work-hardened H14/H18 tube machines and parts off much more cleanly.
Can 3303 be welded?
Readily GTAW/GMAW welded with 1100 or 4043 filler and excellent for furnace/flux brazing; weld metal reverts to O-temper strength so design joints for annealed properties.
Can 3303 be formed, bent or molded?
Excellent cold formability in O/H12 — deep drawing, tube bending, expanding, flaring and roll forming; interanneal at 340–415 °C after heavy reductions.
What surface finishes work on 3303?
Takes protective/hard anodizing and conversion coatings well but goes grey-brown, so specify paint, powder coat or chromate for appearance parts; poor bright polishing.
3303 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 |
|---|---|---|
| SiSi+Fe controlled together in some registrations | ≤ 0.6 | 0.25 |
| Fe | ≤ 0.7 | 0.45 |
| Curaises strength and helps chip break-up | 0.05 – 0.2 | 0.12 |
| Mnprincipal strengthening/dispersoid element | 1 – 1.5 | 1.2 |
| Znhigher Zn allowance than 3003 (scrap tolerance) | ≤ 0.3 | — |
| Others (each) | ≤ 0.05 | — |
| Others (total) | ≤ 0.15 | — |
| Alremainder, ~96.5–97.5 % | balance | — |
3303-H18 — frequently asked
What is 3303-H18 used for?
3303-H18 is typically used for drawn tubing, heat exchanger tubes and general tube stock. In short: tube-drawing 3003 variant; highly formable Al-Mn alloy; brazes and welds readily.
What is the yield strength of 3303-H18?
3303-H18 has a typical yield strength of 185 MPa (26.8 ksi) and a tensile strength of 200 MPa (29 ksi) — weaker than 53% of aluminum grades. Strength varies by condition: see the 7 listed tempers.
Is 3303-H18 easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 72% of aluminum grades). Gummy in O temper — use sharp polished high-rake carbide, high speed and flood emulsion; work-hardened H14/H18 tube machines and parts off much more cleanly.
Can 3303-H18 be welded?
Yes — weldability is rated very good (80/100). Readily GTAW/GMAW welded with 1100 or 4043 filler and excellent for furnace/flux brazing; weld metal reverts to O-temper strength so design joints for annealed properties.
What surface finishes work on 3303-H18?
Takes protective/hard anodizing and conversion coatings well but goes grey-brown, so specify paint, powder coat or chromate for appearance parts; poor bright polishing.
Can 3303-H18 be formed, bent or molded?
Excellent cold formability in O/H12 — deep drawing, tube bending, expanding, flaring and roll forming; interanneal at 340–415 °C after heavy reductions.
What is the maximum service temperature of 3303-H18?
3303-H18 is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 3303-O and 3303-H18?
O is the default condition — pick for maximum ductility in drawn tube that will be bent, expanded, flared or brazed after forming. H18: maximum as-drawn strength and best chip control; almost no remaining bend ductility. Yield strength is 42 MPa in O versus 185 MPa in H18.
Sources
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
- ASTM B210 – Aluminum-Alloy Drawn Seamless Tubes — ASTM International (2019)
- ASM Handbook Vol. 2: Properties and Selection – Nonferrous Alloys — ASM International (1990)
- Aluminum Standards and Data — The Aluminum Association (2017)
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.