Top 5 Aluminum Alloys Used in Die Casting (And How to Choose)

The aluminum casting industry is booming. Experts project it will hit USD 144.74 billion by 2030, with a CAGR of 7.2%. These numbers make sense when you realize that all but one piece of aluminum that ever spread remains useful today. This metal ranks among the most recycled materials worldwide.

Die cast aluminum alloys bring together benefits that make them essential to businesses of all sizes. Their strength-to-weight ratio surpasses other common metals substantially. The material can cut vehicle weight by 30-40% and helps streamline fuel consumption. Die casting with aluminum creates parts with exact dimensions and needs minimal machining. A380 leads the market as the most accessible alloy because it casts well and costs less. Other options like A360, ADC12 (A383), Al-Si11Cu3, and B390 serve specific needs perfectly.

This piece gets into the five best aluminum die casting alloys. You'll learn their unique properties and ideal uses. We'll also cover vital factors to think about when choosing the right aluminum alloy to cast your projects.

A380 Aluminum Alloy

A380 leads the pack among aluminum die casting alloys. It makes up the biggest share of aluminum die castings produced worldwide. This copper-aluminum alloy contains aluminum, silicon, and copper. Its versatile nature and performance make it the go-to choice for many industrial uses.

A380 aluminum alloy properties

The A380 alloy comes from the Al-Si-Cu family. Silicon (7.5-9.5%) helps the material flow smoothly into complex molds during die-casting. Copper content (3-4%) makes the alloy stronger and harder, but reduces how well it resists corrosion.

A380's physical properties make it perfect for die casting:

A380 aluminum alloy shows impressive mechanical properties:

Engineers choose A380 as their default alloy for aluminum die casting. It combines strength, ductility, and castability perfectly. The alloy's high thermal conductivity makes it great for parts that need to stay cool to work well and last long.

A380 aluminum casting material applications

A380 works well in many industries. Car makers use this casting alloy for engine parts, transmission housings, and brackets where they need strength, durability, and lightweight. Electronics manufacturers pick it for housings, LED fixtures, and telecom equipment because it conducts heat well and blocks electromagnetic interference.

Power tool and machinery makers often pick A380 for housings and parts. They like how strong and durable it is, plus how easy it is to machine. Industry data shows the A380 works great in:

• Automotive components and motorcycles
• Recreational vehicles and lawn equipment
• Hand tools and office equipment
• Industrial and outdoor lighting
• Telecommunications devices
• Barbeque grills and housewares
• Escalators and various machinery

The alloy handles pressure well, flows smoothly, and resists hot cracking. These qualities make it perfect for die casting in many different uses . A380's strength under high pressure and heat makes it the top choice for many die-casting projects.

A380 alloy pros and cons

Pros:

1. Exceptional Versatility: A380 combines thermal, casting, and mechanical properties better than other alloys.

2. Superior Castability: The alloy flows easily into complex molds and creates detailed parts with few defects.

3. Excellent Strength-to-Weight Ratio: A380 offers both high strength and light weight—a rare mix in materials.

4. Heat Resistance: This alloy beats other aluminum alloys at handling heat and stress in hot conditions.

5. Anti-Soldering Properties: Tools and dies last longer during manufacturing.

6. Machining and Finishing Ease: A380 cuts cleanly without breaking and takes well to surface treatments like anodization and powder coating.

7. Dimensional Stability: The alloy keeps its shape even with thin walls.

Cons:

1. Limited Corrosion Resistance: High copper content makes it less resistant to corrosion than other aluminum alloys.

2. Cost Factors: Some applications find the A380 expensive to produce.

3. Recycling Challenges: Its mix of materials and impurities can make recycling harder.

4. Temperature Limitations: The relatively low melting point limits use in very hot applications.

A380 aluminum alloy pricing and availability

Aluminum ranks as Earth's third most common element. This abundance keeps prices down and makes the A380 an affordable choice for durable parts and products. Right now (April 2025), A380 aluminum alloy costs about 2,615.52 USD/mt (without VAT) or 2,955.54 USD/mt (with VAT).

S&P Global Commodity Insights checks US North American market prices twice weekly. They look at spot transaction prices for the US A380 secondary alloy that meets specific chemistry requirements. These deals usually involve 45,000 lb truckloads with 30-60 day payment terms.

Platts started tracking A380 secondary aluminum alloy prices in July 1992 when US auto makers asked for it. Their independent price index shows real deals between secondary smelters and parts makers. Smelters, die casters, automakers, and other users now rely on these assessments to set prices.

The futures market also tracks A380 alloy prices. CME Group sells Aluminum A380 Alloy (Platts) Futures contracts for different delivery dates. This helps manufacturers and buyers protect themselves from price changes.

A380 remains the king of aluminum die casting thanks to its great properties and easy availability. Some jobs might need different alloys though. A360 works better for corrosion resistance and strength in hot conditions. A383 (ADC12) makes more detailed parts. B390 resists wear better and offers more hardness. A413 handles pressure better.

A360 Aluminum Alloy

A360 aluminum alloy stands out with its superior corrosion resistance and excellent performance at high temperatures. It's a specialized option you just need for die casting applications. This silicon-rich aluminum alloy has unique qualities that make it valuable in specific industries, even though it's not as common as A380.

A360 aluminum alloy characteristics

A360 has substantially higher silicon content (9.0-10.0%) than most casting alloys. This boosts its fluidity and helps it handle high pressures. The balanced composition has restricted copper levels (≤0.6%), magnesium (0.40-0.60%), and other elements like iron, manganese, zinc, and tin.

A360 aluminum alloy's physical properties make it perfect for specialized applications:

The mechanical properties of A360 aluminum die casting material show impressive strength:

The high silicon content gives A360 excellent pressure tightness and fluidity. The alloy bounces back easily after bending, stretching, or compression. Its best feature is exceptional corrosion resistance, especially at high temperatures. This comes from its limited copper content and higher silicon percentage.

A360 die cast aluminum alloy use cases

A360 aluminum casting material works great in many industries where its unique properties shine:

1. Automotive Components: The alloy works great in high-temperature environments, making it perfect for under-hood automotive parts. Car manufacturers use it for oil pans, controller shells, and motor housings.

2. Marine Applications: Thanks to its great corrosion resistance, A360 is a top choice for outboard motors and marine equipment that faces saltwater.

3. Hydraulic Systems: The material's pressure tightness makes it great for hydraulic cylinders and parts that must not leak.

4. LED Lighting: The alloy's toughness and heat dissipation properties work well for LED lamp housings.

5. Telecommunications: 5G communication boxes use A360 because it stays reliable in all kinds of weather.

A360 aluminum die casting does have its limits. It's tougher to cast than A380, which is why many die casters stick with A380 unless they specifically need A360's properties. Unlike other alloys, A360 won't show a red glow before it melts, which can make casting tricky.

A360 vs A380: key differences

A360 and A380 are both aluminum-silicon alloys, but they're quite different in makeup and performance:

Composition Differences:

• A360 has more silicon (9.0-10.0%) than A380 (7.5-9.5%)
• A360 has way less copper (≤0.6%) than A380 (3.0-4.0%) 
• A360 contains more magnesium (0.40-0.60%) than A380 (≤0.10%)

Performance Differences:

• Corrosion resistance: A360 beats A380 substantially, with a corrosion rate of 0.124mm/year compared to A380's 0.153mm/year 
• Electric potential: A360's electric potential (-400mV) is much higher than A380's (-700mV), letting it form a protective passivation layer against corrosion 
• Melting point: A360 melts at a higher temperature (680°C) than A380 (590°C)
• Thermal conductivity: A360 moves heat better (113 W/m·K) than A380 (96 W/m·K)

NaCl solution tests show A360 creates a protective layer that works between -400mV and +40mV. A380 doesn't have this protection and corrodes right away. The lower copper content in A360 is what makes it resist corrosion so well.

A360 aluminum casting cost considerations

Whatever its better corrosion resistance and high-temperature performance, A360 aluminum alloy comes with some cost challenges. It's harder to cast than A380, which takes more time and money. Most die casters avoid it unless they have to use it, which suggests higher processing costs.

Sometimes A360's special properties are worth the extra cost, especially when you have:

• Parts exposed to harsh environments
• Components that must stay strong at high temperatures
• Applications that need excellent pressure tightness
• Products that must last long in corrosive environments

Engineers need to balance higher production costs against A360's long-term benefits of better durability and performance in tough conditions. Parts that face harsh environments or high temperatures might get better value from A360, even if it costs more upfront.

The choice between A360 and other aluminum die casting alloys depends on what you need. A360 makes more sense when corrosion resistance and high-temperature performance matter more than easy casting and initial costs.

ADC12 (A383 Equivalent) Aluminum Alloy

ADC12 aluminum alloy stands out as one of the top choices for die casting applications worldwide, thanks to its smooth flow and ability to fill complex dies. This Japanese standard alloy matches up with A383 in the United States and EN AC-46000 in Europe. It gives manufacturers a perfect mix of performance and budget-friendly solutions.

ADC12 aluminum alloy overview

ADC12 is an aluminum-silicon-copper alloy made specifically for die casting. The alloy contains 9.6-12% silicon that helps it flow better, plus 1.5-3.5% copper that makes it stronger. These ingredients give ADC12 a tensile strength between 180-230 MPa and a density of about 2.7 g/cm³. That's much lighter than steel.

Let's look at what makes ADC12 great for precision parts:

ADC12 shines in performance. It flows smoothly into complex molds and fills detailed die shapes evenly. While it works great at normal temperatures, it doesn't do as well above 250°C. This limits its use in very hot environments.

Companies use ADC12 a lot in car parts like cylinder head covers, blocks, and sensor brackets. The alloy also works great in electronic equipment, consumer goods, LED lighting, communication gear, and machinery.

ADC12 casting alloy advantages

ADC12 aluminum alloy has several benefits that make it so popular:

The alloy's strength-to-weight ratio beats most casting materials. At 2.7 g/cm³, ADC12 weighs 30% less than steel but still offers 180 MPa tensile strength. This makes it perfect for parts that need to stay light.

The alloy fights off rust well, even in damp places. Parts made from ADC12 can last over five years without any protective coating. This helps products last longer in tough conditions.

ADC12 also casts beautifully. It melts at 580°C and flows into molds with ease. This lets manufacturers create complex shapes that stay true to size. That's crucial for making detailed parts with thin walls or tricky shapes.

More benefits include:

• Easy machining thanks to more silicon
• Great heat transfer for cooling 
• Holds pressure well for leak-free parts 
• Stays accurate in size and shape
• Works with small draft angles for complex designs
• Takes surface treatments well 

But ADC12 does have some drawbacks. The extra copper makes it cost more than options like ADC10. It's also tough to weld normally - it tends to crack unless you use special methods like laser welding at 500-600°C. The material also gets weaker above 250°C.

ADC12 vs A383: what's the difference?

ADC12 and A383 are the same thing. ADC12 is just what Japan calls it, while A383 is the American name. They share the same chemical makeup, mechanical properties, and uses. Most manufacturers can swap one for the other without issues.

Engineers pick these alloys over A380 because they resist hot cracking better and fill dies more easily. ADC12/A383 has more silicon (9.5-11.5%) than A380 (7.5-9.5%), which helps make more detailed parts with complex shapes.

Here's how ADC12/A383 stacks up against other common die casting alloys:

ADC12/A383 handles intricate designs better than A380 because it fills complex molds and thin walls more easily. It's also easier to work with than A360, making it great for complicated aluminum die-casting projects.

ADC12 aluminum alloy pricing and sourcing

Right now (April 2025), ADC12 aluminum alloy costs between $2,482.33 and $2,506.55 per metric ton (without VAT), or about $2,818.71 per metric ton (with VAT). These prices apply to ex-works deals under the JISH2118:2000 standard.

You can get ADC12 from big names like Sigma, Yechiu, Lizhong, Longda, Huajin, Csmet, and Shunbo. Most manufacturers buy it in ingot form for die casting.

Buyers should check that suppliers follow quality standards and deliver material with consistent chemistry. You can find ADC12 pretty easily in markets worldwide, though prices change based on aluminum markets, energy costs, and shipping.

ADC12 hits the sweet spot between performance and price for manufacturers. It fills dies better than cheaper options like ADC10, while staying more affordable and easier to use than premium choices like A360. This makes ADC12 perfect for making complex parts in large numbers without breaking the bank.

Al-Si11Cu3 Aluminum Alloy

Al-Si11Cu3 aluminum alloy stands out for its eutectic composition and great casting properties. This aluminum-silicon-copper alloy gives users the perfect mix of strength, fluidity, and thermal conductivity. It's the lifeblood material that industries need when precision and reliability matter most.

Al-Si11Cu3 alloy composition and properties

The alloy contains aluminum (90.5%), silicon (10.0%), and copper (3.0%). Silicon acts as the main alloying element in this eutectic alloy. The phase diagram stays simple without intermediate compounds. Here's what goes into the mix:

The alloy's tensile strength reaches 310 MPa with a melting point of 577°C. Excellent fluidity helps it fill complex molds with ease . Manufacturers can create detailed parts that have thin walls and complex shapes.

The alloy's mechanical properties meet these minimum standards:

• Tensile strength: 240 MPa minimum 
• Yield strength: 140 MPa minimum
• Elongation: 80% minimum 

Al-Si11Cu3 aluminum die casting applications

The alloy's balanced properties make it perfect for industries of all types. Car makers use this alloy a lot to make wheels and parts that need high strength and good protection against corrosion. The material's light weight helps cars become more fuel-efficient and produce fewer emissions.

You'll find Al-Si11Cu3 in many other places too:

1. Electrical and electronics industries need it for connectors and parts that conduct electricity well 
2. Valve and pump components in general engineering 
3. Gear boxes, engine housings, and valve systems
4. Pistons and wheel rims that must resist wear 

The alloy works great for making complex-shaped parts that need medium strength. Motor shells, brackets, and cover plates often use Al-Si11Cu3. These parts work better because the alloy combines strength, heat conductivity, and stays the same size over time.

Al-Si11Cu3 casting alloy pros and limitations

Advantages:

Al-Si11Cu3 has unique benefits that make it a top choice among die-casting aluminum alloys. The metal flows so well during casting that makers can create complex shapes with very few defects. This helps a lot when making thin-walled parts and intricate designs.

The alloy conducts heat well, which helps manage temperature in hot applications. It resists wear better than many similar alloys, making it great for parts that rub against each other.

The material also gives you:

• Better air tightness in pressurized parts
• Easy machining after casting 
• Great balance of strength and casting ability

Limitations:

The alloy isn't perfect. Its copper content means it doesn't resist corrosion as well as alloys with less copper. While it's strong, specialized alloys like B390 are harder and resist wear better.

Recycling brings its own challenges with composition control. The alloy also doesn't work as well in very hot places, which limits where you can use it.

Al-Si11Cu3 sits right in the middle of aluminum die casting options. It flows better than A380 but can't match A360's corrosion resistance or B390's wear resistance. Engineers pick this alloy when they need balanced properties rather than specialized features.

B390 Aluminum Alloy

B390 aluminum, a hypereutectic alloy, stands out in the die casting world because of its extraordinary hardness and wear resistance. This specialized material contains 16-18% silicon—above the 11.7% saturation point in molten aluminum. Silicon crystals act as reinforcing agents and create a uniquely durable casting alloy.

B390 aluminum alloy strength and hardness

B390 delivers impressive mechanical performance with an ultimate tensile strength of 320-360 MPa and a yield strength of 240-250 MPa. The alloy's exceptional hardness measures 120 HB on the Brinell scale—substantially higher than A380's 80 HB. This superior hardness relates to its remarkable wear resistance and makes it perfect for high-friction applications.

Additional mechanical properties include:

The alloy's thermal conductivity of 130-170 W/m·K helps it dissipate heat effectively in demanding applications. B390 manages to keep a density of 2.74-2.8 g/cm³ with a melting point around 580°C.

B390 best aluminum alloy for casting pistons

Engineers developed B390 for automotive engine blocks, and it excels in applications that need exceptional wear resistance and temperature stability. The alloy proves especially valuable when manufacturing:

• Engine pistons and cylinders that face constant friction and need superior wear resistance 
• Brake systems that must handle extreme mechanical stress 
• Pumps and compressors that require dimensional stability under pressure 
• Valve bodies and sleeve-less piston housings 

High silicon content creates crystalline structures that work as hard bearing material and strengthen castings at elevated temperatures. B390 components maintain their structural integrity even under intense heat and friction, making them the top choice for high-wear automotive applications.

B390 aluminum casting material drawbacks

B390's exceptional properties come with notable challenges. The biggest problem lies in machining—the alloy's silicon crystals wear down tools much faster than typical casting alloys like A380. Casting processes need strict control. Poor melt treatment lets silicon crystals fuse, and they can grow beyond 150 microns, which causes machining problems and stress points.

B390 needs careful handling procedures and specialized equipment. The molten material must stay above 700°C during casting, which causes substantial wear to die cavities, cold chambers, and melting furnaces. Tool life drops by at least 20% compared to A380.

Additional limitations include:

• Lower ductility than other casting alloys
• Reduced corrosion resistance due to high copper content
• Difficult to anodize compared to other aluminum alloys 
• Poor weldability and decreased mechanical properties
•  

Comparison Table

Conclusion

Picking the right aluminum die casting alloy is a vital part of project success. Each option brings unique benefits to specific applications. Five alloys stand out in this detailed analysis with their value propositions. A380 leads the market with versatility and affordable solutions. A360 works best in corrosive environments because of its resistance properties. ADC12 (A383) is a great way to get intricate components that need complex die-filling capabilities. Al-Si11Cu3 delivers balanced performance in a variety of applications. B390 provides unmatched hardness and wear resistance for specialized high-friction uses, though it's harder to work with.

Engineers need to think about several factors to pick the right aluminum casting material. They must review the environmental conditions the component faces, especially when dealing with temperature ranges and corrosive elements. Mechanical requirements like strength, hardness, and wear resistance affect alloy selection by a lot. Production aspects such as castability, machining ease, and costs help narrow down the options. Industry standards often guide material choices, particularly in automotive, aerospace, and medical fields.

These aluminum die casting alloys share some common benefits despite their differences. They weigh less than steel, conduct heat well, and maintain good dimensional stability. Aluminum's recyclability makes these alloys eco-friendly choices - all but one piece of aluminum that ever spread through the world still exists today. This sustainability feature, plus performance advantages, explains why die-cast aluminum parts keep growing popular in industries of all sizes.

The aluminum die casting world will keep changing as manufacturers create new alloys and improve existing ones. These five core options—A380, A360, ADC12, Al-Si11Cu3, and B390—are the foundations of die casting worldwide. Project success depends on finding the perfect material for each application's specific needs and challenges rather than searching for a universal "best" alloy.

FAQs

Q1. What is the most versatile aluminum alloy for die casting?

 A380 is generally considered the most versatile aluminum alloy for die casting. It offers an excellent combination of castability, strength, and cost-effectiveness, making it suitable for a wide range of applications across industries.

Q2. Which aluminum alloy is best for corrosion-resistant die cast parts? 

A360 aluminum alloy is the top choice for corrosion-resistant die cast parts. Its low copper content and high silicon percentage contribute to superior corrosion resistance, especially in marine environments and applications exposed to harsh conditions.

Q3. What aluminum alloy should I choose for complex, thin-walled castings?

 ADC12 (equivalent to A383) is ideal for complex, thin-walled castings. Its high silicon content provides excellent fluidity, allowing it to fill intricate molds and create parts with complex geometries and thin walls.

Q4. Which aluminum alloy offers the best wear resistance for high-friction applications?

 B390 aluminum alloy provides the best wear resistance for high-friction applications. Its high silicon content (16-18%) creates hard silicon crystals within the alloy structure, resulting in exceptional hardness and wear resistance, making it ideal for components like engine pistons and brake systems.

Q5. How do I select the right aluminum alloy for my die casting project? 

Selecting the right aluminum alloy depends on your specific application requirements. Consider factors such as mechanical properties needed (strength, hardness, wear resistance), environmental conditions (temperature, corrosion exposure), production considerations (castability, machining ease), and cost. Consult with die casting experts to determine the best alloy for your unique project needs.