ADC12 Aluminum Alloy: Composition, Properties, Uses & ADC12 vs A380
A complete guide to ADC12 die-casting aluminum alloy: chemical composition, mechanical properties, typical applications, and how ADC12 compares with A380 to help you pick the right alloy.
ADC12 is the most widely used aluminum alloy for die casting. It is an Al-Si-Cu alloy (JIS designation), broadly equivalent to A383 and EN AC-46100 (AlSi9Cu3), prized for its excellent castability, good strength and pressure tightness at low cost. This guide covers ADC12's composition, mechanical properties, typical applications, and how it compares with A380 so you can choose the right alloy.
What is ADC12
- ADC12 is a die-casting aluminum alloy in the Al-Si-Cu family (JIS H 5302).
- International equivalents: A383 (US), EN AC-46100 / AlSi9Cu3 (Europe), often recorded as YL113 / ADC12 in China.
- It is the default alloy for high-pressure die casting because it flows well, fills thin walls, and releases cleanly from the mold.
Chemical composition (typical)
- Silicon (Si): about 9.6 to 12.0%
- Copper (Cu): about 1.5 to 3.5%
- Iron (Fe): up to about 1.3%
- Zinc, Manganese, Magnesium, Nickel, Tin: minor / residual
- Aluminum (Al): balance
Values are typical ranges; exact limits follow the applicable standard.
Mechanical properties (typical, as-cast)
- Tensile strength: about 228 to 310 MPa
- Yield strength: about 150 to 170 MPa
- Elongation: about 1 to 3%
- Hardness: about 80 to 90 HB
- Density: about 2.7 g/cm3
- Melting range: about 515 to 580 C
Typical values; actual results depend on casting and section thickness.
Why ADC12 is so widely used
- Excellent castability and fluidity for thin walls and complex shapes.
- Good pressure tightness, so it holds fluids in housings and pump bodies.
- Good strength-to-cost ratio.
- Good machinability for post-machined features.
- Good thermal conductivity for heat-dissipating parts.
Typical applications
- Gear and reducer housings, gearbox enclosures
- Automotive brackets, covers and housings
- Electrical and electromechanical enclosures
- LED lighting housings and heat sinks
- Pump and valve bodies
- General structural and appearance parts
ADC12 vs A380: how to choose
Both are Al-Si-Cu die-casting alloys with similar behavior; the differences are subtle:
- ADC12 (JIS): excellent castability and pressure tightness; the go-to for thin-wall, leak-tight housings.
- A380 (US, ASTM): very good all-round properties and slightly higher strength in some conditions; common in North America.
- In practice they are often interchangeable; specify ADC12 for pressure-tight housings, or A380 where a customer or regional standard requires it.
Design and finishing notes
- Keep walls uniform (typically 2 to 4 mm) to reduce porosity.
- For fluid-tight parts, combine good casting practice with vacuum impregnation.
- ADC12 takes shot blasting, powder coating and machining well; it is not ideal for bright decorative anodizing due to its high silicon and copper content.
FAQ
Is ADC12 the same as A383
Yes. ADC12 (JIS) is broadly equivalent to A383 (US); their compositions are very close.
Can ADC12 be anodized
It can be surface-treated, but its high silicon and copper content makes bright decorative anodizing difficult; powder coating is usually preferred.
Is ADC12 good for leak-tight housings
Yes. ADC12 has good pressure tightness; combined with vacuum impregnation it reliably holds oil and other fluids.
What is the ADC12 melting point
Its melting range is roughly 515 to 580 C.
We die-cast ADC12 (and A380 on request) on 180 to 500 ton cold-chamber machines, with in-house tooling, CNC machining, impregnation and CMM inspection, on a make-to-drawing / OEM basis. Send your drawing for a quote.