Aluminum 3105-H18
Temper
AA 3105 · UNS A93105 · EN AW-3105, AW 3105 · ISO N31
H18 = strain hardened, full hard
Maximum-strength condition for flat blanks, caps and shims with minimal forming.
Values for the H18 condition
Other 3105 tempers and conditions
3105 is listed in 14 conditions; see the grade overview at 3105.
Compare all 14 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Pick for deep drawing, spinning or severe roll forming where maximum ductility is required. | 55 | 115 | 24 | 28 HB | 43 % IACS |
Slightly strain hardened | Near-annealed 3105 sheet with only incidental work hardening from flattening/handling — softest usable formable temper with high ductility. | 55 | 125 | 22 | 33 HB | 42 % IACS |
Strain hardened and partially annealed, quarter hard | European roofing/rainware temper: quarter-hard strength with restored bend ductility. | 120 | 150 | 6 | 42 HB | 41 % IACS |
Strain hardened, quarter hard | Light temper for parts that still need bending but more stiffness than O. | 130 | 150 | 7 | 40 HB | 41 % IACS |
Strain hardened and stabilized, half hard | Stabilized half-hard sheet specified when age-softening of the Mg-bearing alloy must be avoided. | 145 | 170 | 6 | 47 HB | 41 % IACS |
Strain hardened and partially annealed, half hard | Most common coil-coated building-sheet temper in Europe/Asia: half-hard with good roll-forming ductility. | 145 | 170 | 5 | 48 HB | 41 % IACS |
Strain hardened, half hard | General-purpose half-hard sheet for stamped covers, trim and formed panels. | 150 | 170 | 5 | 46 HB | 41 % IACS |
Strain hardened and partially annealed, between half and three-quarter… | The classic North-American 3105 siding/gutter/trim temper — best balance of strength, roll formability and paint-line behaviour. | 160 | 180 | 8 | 48 HB | 41 % IACS |
Strain hardened and partially annealed, three-quarter hard | Higher-strength stabilized coil for panels needing dent resistance with moderate forming. | 165 | 190 | 4 | 53 HB | 41 % IACS |
Strain hardened, three-quarter hard | Choose for flat panels and shallow-formed parts needing higher stiffness and dent resistance. | 175 | 195 | 4 | 52 HB | 41 % IACS |
Strain hardened and partially annealed, full hard | Stiffest stabilized 3105 coil; use only for flat or lightly bent parts. | 185 | 205 | 3 | 57 HB | 41 % IACS |
Strain hardened and stabilized, full hard | Stabilized full-hard thin strip for caps, closures and flat blanked parts. | 190 | 215 | 3 | 58 HB | 41 % IACS |
H18This page Strain hardened, full hard | Maximum-strength condition for flat blanks, caps and shims with minimal forming. | 195 | 215 | 3 | 57 HB | 41 % IACS |
Strain hardened, extra hard | Extra-hard cold-rolled 3105 above full-hard H18 — maximum strength and springiness with minimal ductility, used for thin coil/fin and roll-formed profiles. | 215 | 230 | 1.5 | 63 HB | 41 % IACS |
What is 3105-H18?
3105-H18 is 3105 in the H18 temper — maximum-strength condition for flat blanks, caps and shims with minimal forming. 3105-H18 has a yield strength of 195 MPa (28.3 ksi) and a tensile strength of 215 MPa (31.2 ksi) — stronger than 51% of aluminum grades. Elongation at break is 3% and the elastic modulus is 69 GPa (10 Msi). 3105-H18 has a density of 2.72 g/cm³ (0.0983 lb/in³), heavier than 57% of aluminum grades. It melts at 635°C (1,175 °F).
Advantages
- Conducts heat well — 172 W/m·K (99.4 BTU/hr·ft·°F), better than 84% of aluminum grades
- Readily welded — 85/100, better than 79% of aluminum grades
- High electrical conductivity — 41 % IACS, better than 78% of aluminum grades
- Good corrosion resistance — 68/100, better than 75% of aluminum grades
Limitations
- Limited ductility — 3%, worse than 79% of aluminum grades
- Hard to polish — 45/100, worse than 76% of aluminum grades
3105-H18 properties
Typical room-temperature values for 3105-H18; 17 are specific to this condition. Other listed values are 3105 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
3105-H18 has a density of 2.72 g/cm³ (0.0983 lb/in³), heavier than 57% of aluminum grades. It melts at 635°C (1,175 °F).
Mechanical10
3105-H18 has a yield strength of 195 MPa (28.3 ksi) and a tensile strength of 215 MPa (31.2 ksi) — stronger than 51% of aluminum grades. Elongation at break is 3% and the elastic modulus is 69 GPa (10 Msi).
Thermal6
3105-H18 is rated for continuous service to 150°C (302 °F). It conducts heat at 172 W/m·K (99.4 BTU/hr·ft·°F), better than 84% of aluminum grades. Thermal expansion is 23.6 µm/m·K (13.1 µin/in·°F).
Electrical3
3105-H18 conducts electricity at 41 % IACS, better than 78% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (68/100), better than 75% of aluminum grades.
Sustainability4
Producing a kilogram of 3105-H18 takes about 200 MJ of energy and emits 12 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 40%.
Manufacturability7
3105-H18's machinability is fair (50/100, worse than 65% of aluminum grades); weldability excellent (85/100); formability fair (40/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 3105-H18
Is 3105 easy to machine?
Soft and gummy — use polished high-rake carbide, high surface speed and flood lubrication to avoid built-up edge; blanking and shearing are preferred over milling for thin coil.
Can 3105 be welded?
Readily GTAW/GMAW/resistance welded with 4043 or 5356 filler (5356 for better colour match after anodizing); HAZ reverts toward O strength, so joints lose H-temper properties.
Can 3105 be formed, bent or molded?
Excellent roll forming, bending and stamping in O/H2x tempers; H14–H18 need generous bend radii and grain-direction control to avoid edge cracking.
What surface finishes work on 3105?
Ideal substrate for coil coating and PVDF/polyester paint after chromate-free pretreatment; clear anodizing gives a dull grey, so anodize only for protection, not appearance.
3105 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 | ≤ 0.6 | 0.3 |
| Fe | ≤ 0.7 | 0.45 |
| Cu | ≤ 0.3 | 0.1 |
| Mn | 0.3 – 0.8 | 0.55 |
| Mg | 0.2 – 0.8 | 0.5 |
| Cr | ≤ 0.2 | 0.05 |
| Zn | ≤ 0.4 | 0.1 |
| Ti | ≤ 0.1 | 0.02 |
| Others (each)0.15 total | ≤ 0.05 | — |
| Al | balance | — |
3105-H18 — frequently asked
What is 3105-H18 used for?
3105-H18 is typically used for roofing panels, siding and sign blanks. In short: budget-friendly; easy shaping.
What is the yield strength of 3105-H18?
3105-H18 has a typical yield strength of 195 MPa (28.3 ksi) and a tensile strength of 215 MPa (31.2 ksi) — stronger than 51% of aluminum grades. Strength varies by condition: see the 14 listed tempers.
Is 3105-H18 easy to machine?
Reasonably — machinability is rated fair (50/100, worse than 65% of aluminum grades). Soft and gummy — use polished high-rake carbide, high surface speed and flood lubrication to avoid built-up edge; blanking and shearing are preferred over milling for thin coil.
Can 3105-H18 be welded?
Yes — weldability is rated excellent (85/100). Readily GTAW/GMAW/resistance welded with 4043 or 5356 filler (5356 for better colour match after anodizing); HAZ reverts toward O strength, so joints lose H-temper properties.
What surface finishes work on 3105-H18?
Ideal substrate for coil coating and PVDF/polyester paint after chromate-free pretreatment; clear anodizing gives a dull grey, so anodize only for protection, not appearance.
Can 3105-H18 be formed, bent or molded?
Excellent roll forming, bending and stamping in O/H2x tempers; H14–H18 need generous bend radii and grain-direction control to avoid edge cracking.
What is the maximum service temperature of 3105-H18?
3105-H18 is rated for continuous use to about 150°C (302 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in 3105-H18?
Yes — 3105-H18 is available for sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
- ASTM B209 / B209M — Aluminum and Aluminum-Alloy Sheet and Plate — ASTM International (2021)
- EN 485-2 — Aluminium and aluminium alloys, sheet, strip and plate: mechanical properties — CEN (2016)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- Aluminum Design Manual — The Aluminum Association (2020)
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.