Choosing the right aluminum alloy is one of the first decisions in a die casting project, and it can affect far more than material cost. The alloy will influence tooling design, filling quality, CNC machining, surface finishing, corrosion performance and long-term part reliability.
Many engineers start by checking strength data. Purchasing teams often start with price, availability and supplier lead time. Both are important, but a good alloy choice must also match the part shape, wall thickness, sealing surfaces, machining areas and final working environment.
A small electronic housing, a robot bracket and a pressure-tight aluminum cover may look similar on a drawing. In production, they may need different alloys. A380, ADC12, A360, A413 and AlSi12 are all common aluminum die casting alloys, but each one solves a different type of problem.
This article compares these five alloys by the factors that matter most in real production: strength, fluidity, corrosion resistance, CNC machining and surface finishing. The goal is to help you choose a suitable alloy before tooling, sampling and mass production begin.
Aluminum Die Casting Alloy Comparison
| Alloy | Best For | Key Advantage | Key Limitation |
|---|---|---|---|
| A380 | General die cast parts | Balanced performance | Not the best corrosion resistance |
| ADC12 | Cost-effective mass production | Good castability | Not always equal to A380 |
| A360 | Corrosion-sensitive parts | Better corrosion resistance | More difficult to cast |
| A413 | Thin-wall or pressure-tight parts | Excellent fluidity | Less flexible for machining and finishing |
| AlSi12 | Complex castings with moderate strength | Excellent castability | Not ideal for high-strength structural parts |
This table gives a useful starting point, but you should not choose an alloy by name only. Wall thickness, flow distance, CNC machining areas, coating needs, sealing surfaces and inspection standards can all change the final choice.
For example, two projects may both specify A380. One part may run smoothly in production, while another may show porosity after deep machining or fail a leak test because the design has thin ribs, poor flow paths or critical sealing faces in risky areas.
This is why alloy selection works best when engineers review the full drawing, not just the material grade.
1. A380 Aluminum Die Casting Alloy
A380 is one of the most common aluminum die casting alloys. Engineers often choose it first because it gives a strong balance of strength, casting quality, machining performance and cost.
A380 fits many general industrial parts. Typical examples include electronic housings, motor housings, brackets, covers, gearbox cases and communication equipment parts. It works well when the design needs practical strength, stable casting and good production efficiency.
The main value of A380 is balance. It fills many common die casting shapes well, supports stable mass production and handles secondary CNC machining better than many high-silicon alloys. This makes it a safe starting point for many commercial and industrial aluminum parts.
A380 also works well when the part needs threaded holes, flat faces, sealing grooves, mounting surfaces or assembly datums. With good casting quality and proper porosity control, CNC machining can produce stable results on A380 parts.
For surface finishing, A380 can support painting, powder coating, plating and other protective coatings. However, it does not offer the best corrosion resistance among aluminum die casting alloys. It works well for many indoor and general industrial uses, but wet, outdoor or salt spray conditions need extra care.
If the part will face moisture, engineers should review the coating plan early. Machined surfaces, screw areas and sealing faces also need attention because these areas often become the first points of corrosion risk.
When should you choose A380?
Choose A380 when your project needs a balanced aluminum die casting alloy for housings, covers, brackets, frames or mechanical parts. It is also a good choice when the part needs CNC machining after casting.
When is A380 not the best choice?
A380 may not be the best option when corrosion resistance comes first. It may also cause problems in very thin-wall parts or projects that need high-end decorative anodizing. In these cases, the casting and finishing plan should be reviewed before tooling starts.
2. ADC12 Aluminum Die Casting Alloy
ADC12 is very common in Asian die casting supply chains. Many die casters choose it for mass production because it offers good flow, stable casting performance and competitive cost.
Buyers often compare ADC12 with A380 because both alloys can work for housings, covers, brackets and general mechanical parts. However, ADC12 and A380 are not the same alloy, so engineers should not replace one with the other without a technical review.
ADC12 usually gives good casting performance. It fills medium-complexity parts well and works for ribs, bosses and many commercial die cast shapes. This makes it practical for cost-sensitive projects where the design does not require extreme corrosion resistance or high structural performance.
The main risk comes from material standards and customer approval. A European or North American drawing may specify A380, while an Asian supplier may suggest ADC12 because of cost or local supply. That change may work, but the customer and engineering team should approve it first.
Before switching from A380 to ADC12, check chemical composition, mechanical properties, surface finish, corrosion tests and customer-specific rules. This step can prevent problems during inspection, assembly or long-term use.
ADC12 vs A380: are they the same?
No. ADC12 and A380 can serve similar applications, but they are not fully equal. The right choice depends on the drawing standard, final use, surface finish and testing requirements.
When should you choose ADC12?
Choose ADC12 for cost-sensitive medium- to high-volume die casting projects. It works well for general housings, covers, brackets and mechanical components. Do not choose ADC12 only because it costs less; first make sure it can meet the product requirements.
3. A360 Aluminum Die Casting Alloy
A360 is a better choice when corrosion resistance matters more. Compared with A380 and ADC12, it gives stronger corrosion performance and better strength at higher temperatures.
Engineers often review A360 for outdoor parts, marine-related electronics, sensor housings, telecom equipment and components that face humidity. It can also work well near motors, power electronics or parts that experience moderate heat.
A360 gives useful performance benefits, but it also needs tighter casting control. It is harder to cast than A380, so the die caster must control gate design, overflow layout, venting, die temperature, melt quality and filling speed more carefully.
For thin walls or long flow paths, the team should check casting feasibility before tooling. Complex ribs, deep pockets and sharp transitions need special attention because they can increase filling risk.
If the part also needs CNC machining, engineers should review the machining areas early. Coating requirements also deserve early discussion because corrosion-sensitive parts often have strict finishing needs.
A360 can be an excellent alloy choice, but you should not choose it only because the project mentions corrosion resistance. The part design, coating plan and production volume still need a complete review.
When should you choose A360?
Choose A360 for outdoor, humid or corrosion-sensitive parts. It also suits some marine-related housings, telecom housings and parts that work under moderate heat.
What should you check before using A360?
Check wall thickness, flow length, sealing areas, cosmetic surfaces and machining positions. You should also review coating needs and annual volume because a difficult design can raise cost even when the alloy choice is correct.
4. A413 Aluminum Die Casting Alloy
A413 offers excellent fluidity and pressure tightness. Engineers often choose it for thin-wall, complex or sealed die cast parts.
Its high silicon content helps molten metal flow into thin sections, small details, long flow paths and complex ribs. This makes A413 useful when a part has difficult filling areas and a general-purpose alloy may not fill the cavity well enough.
A413 also works well for pressure-tight parts. Typical examples include sealed covers, leak-tested housings and fluid-related enclosures. However, alloy choice alone does not create a pressure-tight casting. Tooling and process control also play a major role.
The die caster must design the gate, overflow and venting system carefully. Ejector pin layout also matters because poor placement may create porosity near critical surfaces.
A413 has limits in machining and finishing. High-silicon alloys can increase tool wear and may give less stable results in polishing or decorative anodizing. If the part needs many machined holes, sealing grooves or visible surfaces, the team should discuss these points before tooling.
When should you choose A413?
Choose A413 for thin-wall aluminum castings, complex shapes and pressure-tight parts. It is especially useful when the part has filling challenges or leak test requirements.
What are the limitations of A413?
A413 is not the best choice for maximum machining flexibility. It is also not ideal for premium decorative anodizing. You can still machine and finish A413 parts, but the project needs a clear process plan from the beginning.
5. AlSi12 Aluminum Die Casting Alloy
AlSi12 has high silicon content, so it offers excellent castability and good corrosion resistance. In real sourcing, the term “AlSi12” may refer to different regional standards, so the engineering team should always confirm the exact material grade.
The main advantage of AlSi12 is fluidity. It fills complex shapes, thin walls and detailed features well. This makes it useful for covers, housings, thin-wall structures and parts that need moderate strength rather than high structural strength.
AlSi12 is not usually the first choice for high-load structural parts. It may not suit designs that need high impact strength, strict mechanical performance or heavy post-machining.
Surface finishing also needs review. High-silicon alloys cast well, but they may not give the best decorative finish. Powder coating, painting and conversion coating may work well, while decorative anodizing may look less even. If appearance matters, discuss the expected finish before material approval.
When should you choose AlSi12?
Choose AlSi12 when the part has complex geometry or thin sections. It also suits parts where castability matters more than high strength.
What should you confirm before using AlSi12?
Confirm the exact standard, chemical composition and mechanical requirements. You should also check surface finish, corrosion needs and final working conditions.
How Do You Choose the Right Aluminum Alloy for Die Casting?
The right alloy depends on the part function, geometry and production needs. A380 is a strong starting point for general-purpose die castings. ADC12 works well for cost-sensitive mass production. A360 helps when corrosion resistance matters more.
A413 is a strong option for thin-wall or pressure-tight parts. AlSi12 works well when the part needs excellent castability and moderate strength.
What strength level does the part need?
Strength matters, but it should not be the only factor. For general housings, covers and brackets, A380 or ADC12 may work well. For load-bearing parts, the team should review wall thickness, rib design, screw bosses, mounting points, load direction and test requirements. A stronger data sheet does not always create a better casting. If the alloy does not suit the geometry, the part may have more porosity, more casting defects or higher machining risk.
Does the part have thin walls or complex geometry?
Thin walls and long flow paths need good fluidity. Deep ribs, small bosses and complex shapes also increase filling risk. A413 and AlSi12 often help in these cases, but alloy alone cannot solve all filling problems. Gate design, venting, overflows, die temperature and injection parameters also affect filling quality. Your team should review the 3D model before tooling. Small design changes can prevent major casting problems.
Will the part face corrosion?
A380 and ADC12 may work well in dry indoor use. Outdoor, humid or salt spray conditions need more care, so the team should review A360 or a stronger surface protection plan. Corrosion performance depends on more than alloy choice. Coating, sealing design, fasteners and drainage all matter. Machined surfaces need special attention because machining removes the original casting skin and may expose areas that need extra protection.
How much CNC machining does the part need?
CNC machining can change the alloy decision. If the part needs many machined holes, threads or flat faces, choose an alloy with stable cutting behavior. A380 and ADC12 usually work well for machined die cast parts. A413 and AlSi12 can also be machined, but the team should review tool wear, burrs, pores and surface finish early. The drawing should define as-cast areas and machined areas clearly.
What surface finish does the part need?
Discuss surface finish before tooling. Do not wait until mass production starts. Aluminum die castings can use painting, powder coating, plating, chemical treatment or anodizing. Painting and powder coating are common choices because they improve appearance and corrosion protection.
Chemical conversion coating can help when the part needs corrosion resistance and electrical function. Anodizing may work in some cases, but decorative anodizing on die cast aluminum often looks less even than on wrought aluminum. If appearance matters, set clear samples and acceptance standards early.
What Mistakes Should You Avoid When Selecting Aluminum Die Casting Alloys?
Are you choosing the alloy only by strength?
This is a common mistake. Tensile strength and yield strength matter, but they do not tell the full story. The alloy must fill the cavity well, release from the die, machine cleanly and accept the required finish. The best alloy meets the engineering need and also supports stable production.
Are you treating A380 and ADC12 as the same alloy?
A380 and ADC12 can work for similar parts, but they are not automatically the same. If a drawing specifies A380 and the supplier suggests ADC12, review the change first. Check chemical composition, mechanical properties, finishing, corrosion needs and customer approval rules. This matters most when European or North American buyers source parts from Asian die casting suppliers.
Are you ignoring surface finishing before tooling?
Surface finishing can affect alloy choice. A part that only needs powder coating may allow more alloy options, while a visible decorative part may need stricter review. A salt spray part may also need a stronger coating system. Check coating thickness, masking areas and conductive surfaces before tooling.
Are you discussing porosity too late?
Porosity can create many problems. It may appear during CNC machining, or it may cause leaks and coating defects. If the part has deep machining, gasket grooves or leak tests, review porosity risk early. Gate location, overflow design, venting and melt quality all affect porosity. It costs less to reduce porosity risk before tooling than after machining exposes it.
Need Help Choosing an Aluminum Die Casting Alloy?
Choosing the right aluminum alloy is only one step. Tooling design, gate layout, melt quality, process control, CNC machining and surface finishing also shape final quality.
Sunrise Casting helps customers review aluminum die casting projects from the early design stage. Our team can support material selection, DFM review, tooling, die casting, CNC machining and surface finishing. We work with aluminum parts for industrial equipment, electronic housings, robotic components and precision mechanical assemblies.
Contact us and send your 2D drawing, 3D model, annual volume, surface finish requirement and working environment. Our engineering team will help you review whether A380, ADC12, A360, A413 or AlSi12 is the right choice for your die casting project.
