Aluminum ADC12-O (Annealed)
Temper
JIS ADC12
Use when residual stress relief and long-term dimensional stability matter more than strength (precision housings, optical mounts).
Values for the O condition
Other ADC12 tempers and conditions
ADC12 is listed in 5 conditions; see the grade overview at ADC12.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
OThis page Annealed | Use when residual stress relief and long-term dimensional stability matter more than strength (precision housings, optical mounts). | 115 | 240 | 4.5 | 62 HB | 28 % IACS |
FDefault As fabricated | Standard supply condition for virtually all ADC12 high-pressure die castings. | 155 | 310 | 2.5 | 80 HB | 23 % IACS |
F | Choose for pressure-tight, weldable or heat-treatable ADC12 parts where standard HPDC porosity is unacceptable. | 160 | 320 | 4 | 80 HB | 24 % IACS |
Cooled from hot working and artificially aged | Pick when a modest strength/hardness gain and dimensional stability are needed without the blister risk of solution treatment. | 200 | 330 | 1.5 | 90 HB | 24.5 % IACS |
Solution heat treated and artificially aged | Only for high-vacuum or squeeze-cast ADC12 where gas porosity is low enough to avoid blistering; gives the highest strength but very low ductility. | 260 | 340 | 1 | 110 HB | 26 % IACS |
What is ADC12-O?
ADC12-O is ADC12 in the O temper — use when residual stress relief and long-term dimensional stability matter more than strength (precision housings, optical mounts). ADC12-O has a yield strength of 115 MPa (16.7 ksi) and a tensile strength of 240 MPa (34.8 ksi) — weaker than 79% of aluminum grades. Elongation at break is 4.5% and the elastic modulus is 71 GPa (10.3 Msi). ADC12-O has a density of 2.74 g/cm³ (0.099 lb/in³), heavier than 64% of aluminum grades. It melts at 515°C (959 °F). F is the default condition FabDigit quotes; O is available on request or by drawing note.
Advantages
- High service temperature — 200°C (392 °F), better than 90% of aluminum grades
Limitations
- Hard to polish — 40/100, worse than 91% of aluminum grades
- Poor heat conductor — 115 W/m·K (66.4 BTU/hr·ft·°F), worse than 85% of aluminum grades
- Low fracture toughness — 17 MPa·√m (15.5 ksi·√in), worse than 83% of aluminum grades
- Difficult to weld — 22/100, worse than 83% of aluminum grades
- Low electrical conductivity — 28 % IACS, worse than 82% of aluminum grades
ADC12-O properties
Typical room-temperature values for ADC12-O; 21 are specific to this condition. Other listed values are ADC12 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
ADC12-O has a density of 2.74 g/cm³ (0.099 lb/in³), heavier than 64% of aluminum grades. It melts at 515°C (959 °F).
Mechanical15
ADC12-O has a yield strength of 115 MPa (16.7 ksi) and a tensile strength of 240 MPa (34.8 ksi) — weaker than 79% of aluminum grades. Elongation at break is 4.5% and the elastic modulus is 71 GPa (10.3 Msi).
Thermal6
ADC12-O is rated for continuous service to 200°C (392 °F). It conducts heat at 115 W/m·K (66.4 BTU/hr·ft·°F), worse than 85% of aluminum grades. Thermal expansion is 21.1 µm/m·K (11.7 µin/in·°F).
Electrical3
ADC12-O conducts electricity at 28 % IACS, worse than 82% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 62% of aluminum grades.
Sustainability4
Producing a kilogram of ADC12-O takes about 180 MJ of energy and emits 11.5 kg of CO₂ — less than 91% of aluminum grades. Typical recycled content is 90%.
Manufacturability8
ADC12-O's machinability is good (62/100, better than 55% of aluminum grades); weldability poor (22/100); formability not recommended (14/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with ADC12-O
Is ADC12 easy to machine?
Machines fast and gives short chips, but the eutectic Si is abrasive — use PCD or diamond-coated carbide, high speed, low feed, and flood coolant; watch subsurface porosity when boring sealing faces.
Can ADC12 be welded?
Not recommended for conventional HPDC parts (entrapped gas blisters and cracks); use mechanical joining, adhesive, or TIG/friction-stir only on vacuum-cast or thick sound sections with ER4047 filler.
Can ADC12 be formed, bent or molded?
Designed for cold-chamber high-pressure die casting at ~660–690 °C metal temperature with 0.8–3 mm walls; excellent fluidity and low hot-tearing, keep Fe ≥0.7% to avoid die soldering, no cold forming possible.
What surface finishes work on ADC12?
Best finished by chromate-free conversion coating plus powder coat or paint; decorative anodizing gives a dark mottled grey, and electroless nickel or shot blasting are common for wear or uniform matte appearance.
ADC12 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 |
|---|---|---|
| SiJIS H5302 ADC12 | 9.6 – 12 | 11 |
| Cu | 1.5 – 3.5 | 2.5 |
| Mg | ≤ 0.3 | 0.15 |
| Zn | ≤ 1 | 0.5 |
| Fekept ≥0.7 in practice to prevent die soldering | ≤ 1.3 | 0.9 |
| Mn | ≤ 0.5 | 0.2 |
| Ni | ≤ 0.5 | 0.1 |
| Sn | ≤ 0.3 | 0.05 |
| Al | balance | — |
ADC12-O — frequently asked
What is ADC12-O used for?
ADC12-O is typically used for automotive housings, electronics enclosures, motor casings and consumer product castings. In short: most available die-cast alloy; best castability and die life; not for structural welding.
What is the yield strength of ADC12-O?
ADC12-O has a typical yield strength of 115 MPa (16.7 ksi) and a tensile strength of 240 MPa (34.8 ksi) — weaker than 79% of aluminum grades. Strength varies by condition: see the 5 listed tempers.
Is ADC12-O easy to machine?
Reasonably — machinability is rated good (62/100, better than 55% of aluminum grades). Machines fast and gives short chips, but the eutectic Si is abrasive — use PCD or diamond-coated carbide, high speed, low feed, and flood coolant; watch subsurface porosity when boring sealing faces.
Can ADC12-O be welded?
Not readily — weldability is rated poor (22/100). Not recommended for conventional HPDC parts (entrapped gas blisters and cracks); use mechanical joining, adhesive, or TIG/friction-stir only on vacuum-cast or thick sound sections with ER4047 filler.
What surface finishes work on ADC12-O?
Best finished by chromate-free conversion coating plus powder coat or paint; decorative anodizing gives a dark mottled grey, and electroless nickel or shot blasting are common for wear or uniform matte appearance.
Can ADC12-O be formed, bent or molded?
Designed for cold-chamber high-pressure die casting at ~660–690 °C metal temperature with 0.8–3 mm walls; excellent fluidity and low hot-tearing, keep Fe ≥0.7% to avoid die soldering, no cold forming possible.
What is the maximum service temperature of ADC12-O?
ADC12-O 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 ADC12-F and ADC12-T6?
F is the default condition — standard supply condition for virtually all ADC12 high-pressure die castings. T6: only for high-vacuum or squeeze-cast ADC12 where gas porosity is low enough to avoid blistering; gives the highest strength but very low ductility. Yield strength is 155 MPa in F versus 260 MPa in T6.
Sources
- JIS H 5302 — Aluminium alloy die castings — JSA (2006)
- GB/T 15115 — (YL113) — SAC (2009)
- EN 1706 — Aluminium and aluminium alloys, castings (EN AC-46000) — CEN (2020)
- ASTM B85 / A383.0 die casting alloy — ASTM (2018)
- ASM Handbook Vol.2 — Properties of Aluminum Casting Alloys — ASM International (1990)
- ASM Handbook Vol.15 — Casting — ASM International (2008)
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.