Aluminum Die Casting Alloys
Composition, mechanical properties and honest trade-offs for the four alloys we cast — plus the selection logic that decides between them.
Four production alloys, one selection decision
Aluminum die casting alloys are aluminum-silicon alloys containing 7.5 to 13% silicon, injected into a steel die under high pressure. CharMax Precision casts four production grades: A380 as the general-purpose default, ADC12 for thin walls and Asian standards, A360 for corrosion resistance and pressure tightness, and A413 where thermal conductivity governs.
Silicon is what makes the family castable. It raises fluidity so metal reaches thin sections before freezing, and because silicon expands slightly on solidification it offsets part of aluminum's 6.6% volumetric contraction. Everything else in the chemistry is a trade: copper buys strength and machinability at the cost of corrosion resistance, magnesium buys yield strength at the cost of ductility, and iron is added deliberately to stop the melt attacking the die steel.
Tensile strength varies by less than 10% across the four grades, so strength is rarely the deciding factor. The properties that actually separate them are corrosion resistance, pressure tightness, thermal conductivity, minimum wall thickness and cost. Every ingot lot is verified on an optical emission spectrometer before it enters the furnace, and lots stay traceable from ingot to casting batch.
Alloy capability summary
| Production alloys | A380, ADC12, A360, A413 |
|---|---|
| Alloy family | Aluminum-silicon, AA 3xx.x and 4xx.x |
| Silicon range | 7.5-13.0% |
| Tensile strength range | 296-324 MPa as cast |
| Yield strength range | 145-170 MPa |
| Density range | 2.63-2.74 g/cm³ |
| Thermal conductivity | 96-121 W/m·K |
| Standards supported | ASTM B85, JIS H 5302, EN 1706, GB/T 15115 |
| Wall thickness | 1.5 mm typical, 1.0 mm achievable on small parts |
| Volume range | 500 to 500,000+ parts per year |
| Verification | Spectrometer check on every ingot lot |
Explore each aluminum die casting alloy
Every alloy page covers full chemical composition, as-cast mechanical and physical properties, advantages, limitations and the applications the grade is genuinely suited to.
A380 Aluminum Die Casting Alloy
The general-purpose workhorse alloy. Best all-round balance of strength, castability, machinability and cost.
- 324 MPa tensile strength
- Excellent castability
- Most economical option
ADC12 Aluminum Die Casting Alloy
The JIS equivalent of A383, widely specified in Asia for thin-wall parts and complex geometry.
- Superior thin-wall filling
- JIS H 5302 standard
- Strong dimensional stability
A360 Aluminum Die Casting Alloy
Higher corrosion resistance and better pressure tightness for sealed and outdoor housings.
- Best corrosion resistance
- Excellent pressure tightness
- Higher yield strength than A380
Aluminum-Silicon Die Casting Alloys
The Al-Si alloy family behind every die casting alloy, including EN AC-46000 and AlSi9Cu3 grades.
- 8-12% silicon content
- European EN AC grades
- Alloy selection guidance
Aluminum casting alloy comparison
One master table, used on every alloy page and the homepage, so no published figure on this site can disagree with another. Values are typical as-cast properties measured on separately cast test bars.
| Property | A380 (AlSi8Cu3Fe) | ADC12 (A383) | A360 (AlSi10Mg) | A413 (AlSi12) |
|---|---|---|---|---|
| Ultimate tensile strength | 324 MPa (47 ksi) | 310 MPa (45 ksi) | 317 MPa (46 ksi) | 296 MPa (43 ksi) |
| Yield strength (0.2%) | 159 MPa (23 ksi) | 150 MPa (22 ksi) | 170 MPa (25 ksi) | 145 MPa (21 ksi) |
| Elongation in 50 mm | 3.5% | 3.5% | 3.5% | 2.5% |
| Brinell hardness | 80 HB | 75 HB | 75 HB | 80 HB |
| Silicon content | 7.5-9.5% | 9.6-12.0% | 9.0-10.0% | 11.0-13.0% |
| Copper content | 3.0-4.0% | 1.5-3.5% | 0.6% max | 1.0% max |
| Density | 2.74 g/cm³ | 2.70 g/cm³ | 2.63 g/cm³ | 2.66 g/cm³ |
| Thermal conductivity | 96 W/m·K | 96 W/m·K | 113 W/m·K | 121 W/m·K |
| Castability | Excellent | Excellent | Very good | Excellent |
| Corrosion resistance | Fair | Fair | Good | Good |
| Machinability | Very good | Good | Good | Fair |
| Pressure tightness | Good | Good | Excellent | Excellent |
| Relative cost | Lowest | Low | Moderate | Moderate |
Properties are typical as-cast values measured on separately cast test bars and will vary with wall thickness, gating and section geometry. Request a material certificate for lot-specific values.
How to choose a die casting alloy
Start from A380 and move away from it only when a specific requirement forces the move. That sounds glib, but it reflects how the trade-offs actually line up: A380 has the widest process window, the best machinability and the lowest cost, so every alternative has to justify a price or yield penalty with a property the part genuinely needs.
Three requirements justify the move often enough to be worth naming. Thin walls push toward ADC12, because its 9.6 to 12.0% silicon keeps more metal liquid late in solidification and fills sections that A380 leaves as cold shuts. Corrosion exposure and sealing push toward A360, because copper at 0.6% maximum instead of 3.0 to 4.0% removes the galvanic driver of pitting and leaves fewer interdendritic leak paths. Heat dissipation pushes toward A360 or A413, whose 113 and 121 W/m·K conductivity beats the 96 W/m·K of the copper-bearing grades.
Heavy machining after casting pushes the other way, back toward A380. Copper hardens the matrix enough that chips break instead of smearing, so insert life is longer and cycle time shorter. Where a part has both thin walls and heavy machining, we will quote both alloys so the comparison sits on paper rather than on assumption.
| If your priority is | Recommended alloy | Why |
|---|---|---|
| Lowest piece price at volume | A380 | Best castability and tool life, widest supply, easiest to machine |
| Thin walls below 2 mm | ADC12 | Higher silicon improves flow into thin sections and long flow paths |
| Highest tensile strength | A380 | 324 MPa, the highest of the common die casting alloys |
| Highest yield strength | A360 | 170 MPa against A380's 159 MPa, despite slightly lower tensile strength |
| Corrosion resistance outdoors | A360 | Low copper content substantially improves corrosion performance |
| Pressure-tight or sealed housings | A360 | Excellent pressure tightness for hydraulic and IP-rated enclosures |
| Heat dissipation | A360 or A413 | Higher thermal conductivity than copper-bearing A380 |
| Heavy machining after casting | A380 | Highest machinability rating of the common die casting alloys |
| Asian supply chain alignment | ADC12 | JIS standard grade, most widely stocked alloy in Asia |
Die casting alloys are not the same as machining alloys
The most frequent material question we receive is whether a part can be die cast in 6061 or 7075. It cannot, and the reason is worth understanding before a drawing is released.
Die casting alloys are aluminum-silicon alloys with 7.5 to 13% silicon. That silicon is not incidental: it provides the fluidity that lets metal reach a 1.5 mm wall before freezing, and it offsets part of aluminum's solidification shrinkage so the casting does not tear itself apart inside a rigid steel die. Casting alloys also carry 0.6 to 1.3% iron on purpose, which saturates the reaction between molten aluminum and the H13 die steel and stops the casting welding itself to the cavity.
Wrought alloys are built for the opposite process. 6061 is an Al-Mg-Si alloy with 0.4 to 0.8% silicon and 7075 is an Al-Zn-Mg-Cu alloy with 0.40% silicon maximum; both are designed to be extruded or rolled and then solution treated and aged, and both are formulated to keep iron low because iron reduces toughness. Put either in a die casting machine and you get hot tearing, die soldering and no useful fill. It is a process incompatibility rather than a difficulty to be engineered around.
The practical consequence is a fork in the road at design release. Production volumes with complex geometry, thin walls and cast-in features belong in die cast A380 or ADC12. Low volumes, tight tolerances, high yield strength and bright anodized finishes belong in machined 6061 or 7075. CharMax Precision runs both, so the honest answer does not cost us the work either way.
| Property | A380 (die casting alloy) | 6061-T6 (wrought) | 7075-T6 (wrought) |
|---|---|---|---|
| Form supplied | Remelt ingot, injected as liquid metal | Extruded bar, plate and tube | Rolled plate and bar |
| Silicon content | 7.5-9.5% | 0.4-0.8% | 0.40% max |
| Tensile strength | 324 MPa as cast | 310 MPa | 572 MPa |
| Yield strength | 159 MPa | 276 MPa | 503 MPa |
| Elongation | 3.5% | 8-12% | 7-11% |
| How it is shaped | Injected into a steel die at 40-100 MPa and solidified in seconds | Machined, formed or extruded from solid stock | Machined from solid stock |
| Can it be die cast | Yes, designed for it | No, hot tears and solders to the die | No, cracks during solidification |
| Minimum wall thickness | 1.5 mm typical, 1.0 mm on small parts | About 0.8 mm machined, limited by tool deflection | About 0.8 mm machined |
| Best annual volume | 1,000 to 500,000+ parts | 1 to 500 parts | 1 to 500 parts |
| Tooling required | Steel die, 3,000-25,000 USD | Fixtures only | Fixtures only |
| Anodizing appearance | Grey and mottled from high silicon | Clear, bright and uniform | Uniform, slightly less bright than 6061 |
6061 and 7075 get their properties from rolling or extrusion followed by solution treatment and ageing, none of which is available to a high pressure die casting. Note that A380 as cast actually exceeds 6061-T6 in ultimate tensile strength while falling well short on yield strength and elongation, so the comparison only favours casting for parts loaded inside the elastic range. If your drawing calls for 6061-T6 or 7075-T6, the part should be machined from billet.
Related capabilities and resources
Manufacturing services
Part types we produce
Industries served
Need machined aluminum parts instead of castings?
Die casting pays for itself above roughly 1,000 parts per year. Below that, or while you are still validating a design, CNC machining from billet is usually the faster and cheaper route. CharMax Precision runs a dedicated aluminum CNC machining operation for exactly that work, so you can prototype machined, then move to casting when volume justifies tooling.
Questions about aluminum die casting alloys
Which aluminum alloy is best for die casting?
A380 is the best default choice for most die cast parts. It has the widest process window, the best machinability of the common alloys and the lowest piece cost, and it reaches 324 MPa tensile strength as cast. Move away from A380 only when a specific requirement forces the move: ADC12 for walls below 1.5 mm or long flow paths, A360 for outdoor corrosion resistance, pressure-tight housings and heat dissipation, and A413 where thermal conductivity is the dominant requirement.
Can 6061 or 7075 aluminum be die cast?
No. 6061 and 7075 are wrought alloys and cannot be die cast. 6061 contains only 0.4 to 0.8% silicon and 7075 contains 0.40% maximum, far below the 7.5 to 13% that die casting alloys need to feed thin sections, so both hot tear in a constrained steel die and both solder to die steel. Their properties also depend on rolling or extrusion followed by solution treatment and ageing, and a high pressure die casting cannot be solution treated because entrapped gas blisters the surface. Parts specified in 6061-T6 or 7075-T6 must be machined from billet.
What is the difference between A380 and ADC12?
Silicon content is the practical difference. ADC12 carries 9.6 to 12.0% silicon against A380's 7.5 to 9.5%, which puts it closer to the aluminum-silicon eutectic and lets it fill thinner walls and longer flow paths. A380 is stronger and harder at 324 MPa and 80 HB against 310 MPa and 75 HB, machines more freely because its 3.0 to 4.0% copper helps chips break, and costs slightly less. A380 is also the ASTM grade while ADC12 is the JIS grade, which is why ADC12 dominates Asian supply chains.
Which alloy should I specify for an outdoor enclosure?
A360, coated. Copper is what drives corrosion in a die casting, and A360 caps it at 0.6% maximum against 3.0 to 4.0% in A380, which lifts corrosion resistance from fair to good. A360 also gives excellent pressure tightness for IP-rated sealing and the highest yield strength of the common alloys at 170 MPa. It still needs a finish for outdoor service: chromate conversion coating plus powder coat is the standard specification, and the advantage of A360 is that a coating scratch does not immediately become a corrosion site.
Which die casting alloy conducts heat best?
A413 conducts best at 121 W/m·K, followed by A360 at 113 W/m·K, with A380 and ADC12 both at 96 W/m·K. Copper in solid solution is what suppresses conductivity, so the low-copper grades win. In practice A360 is specified more often than A413 for heat sink housings, because A413 gives up yield strength, at 145 MPa against 170 MPa, and rates only fair for machinability. If the part is purely a heat sink with minimal machining, A413 is worth considering.
Can you cast to a European EN AC or Chinese GB grade?
Yes. EN AC-46000, EN AC-47100, EN AC-43400 and EN AC-44300 are the European equivalents of A380, ADC12, A360 and A413, and YL112, YL113, YL104 and YL102 are the Chinese GB/T 15115 equivalents. Where a drawing names an EN or GB grade as a specification requirement, we buy ingot to that chemistry and certify against that standard rather than substituting the nearest alloy. Copper limits are where the systems diverge most, so name the governing standard on your drawing and we will confirm it on the quotation.
Do you verify alloy chemistry and issue material certificates?
Yes. Every incoming ingot lot is checked on an optical emission spectrometer against the supplier certificate before it enters the furnace, and lots stay traceable from ingot to casting batch. Material certificates, RoHS declarations and PPAP or first article documentation are issued on request. If your drawing narrows a composition range beyond the standard specification, for example holding copper to a tighter band within ADC12's 1.5 to 3.5%, we buy ingot to your range and certify to it.
What files do you need to quote?
A 3D model in STEP, IGES, X_T, SLDPRT or native CAD format, plus a 2D drawing showing critical dimensions, tolerances, surface finish, alloy and any inspection requirements. If you only have a 3D model we can still quote, but a drawing that marks which features are critical to function will get you a more accurate price and prevent misunderstandings later.
Not sure which alloy your part needs?
Send your 2D drawing and 3D model with the service environment, sealing pressure or thermal target the part has to meet. We will recommend an alloy, explain the trade-off in writing, and quote piece price and tooling against it.
- Engineering response within 24 hours on business days
- Quotation within 24-48 hours of receiving 2D/3D files
- NDA signed before file review
- Free DFM feedback