Introduction
You picked A360 aluminum because you need parts that resist rust. You expected them to last in wet or salty conditions. But now you face problems. The metal does not flow well. Thin sections of your parts stay incomplete. Some castings break under normal loads. Others show rust spots in some areas but not others. Cycle times run long. Dies wear out fast. And your fluid-handling parts leak during pressure tests.
You are not alone. A360 is a specialized alloy. It offers great corrosion resistance. But it demands a different approach than standard alloys like A380 or A383.
This guide explains how to make A360 work. You will learn what makes it resist corrosion. You will see why it behaves differently in the die. You will get practical steps to fix common problems. And you will know if this alloy truly fits your application.
What Makes A360 Different?
The Chemistry Behind Corrosion Resistance
A360 is built for harsh environments. Its formula focuses on one thing: keeping copper out.
| Element | A360 Content | Why It Matters |
|---|---|---|
| Copper | 0.1% max | Copper causes rust. Less copper means better corrosion resistance. |
| Silicon | 9-10% | Helps flow. Lower than A383 but enough for most parts. |
| Magnesium | 0.4-0.6% | Boosts strength and helps form protective oxide layer. |
| Aluminum | Remainder | Base material that forms natural rust barrier. |
This low-copper formula gives A360 its superpower. It forms a dense oxide layer that blocks moisture. In salt spray tests, A360 lasts 240+ hours without visible corrosion. A380 typically fails within 96 hours.
Mechanical Properties That Work
A360 is not the strongest aluminum alloy. But it offers enough strength for most corrosion-critical parts.
| Property | Typical Value | Best For |
|---|---|---|
| Tensile Strength | 240-280 MPa | Parts that see moderate loads |
| Yield Strength | 140-160 MPa | Components that should not bend |
| Elongation | 6-8% | Good flexibility before cracking |
| Hardness | 70-80 HB | Moderate wear resistance |
Real example: A marine equipment maker switched from A380 to A360 for boat pump housings. Tensile strength dropped from 310 MPa to 260 MPa. But the parts lasted 3 times longer in saltwater. The client saved $50,000 per year in warranty claims.
Why Is A360 So Hard to Cast?
The Fluidity Challenge
A360 does not flow like A383. Its lower silicon content (9-10% vs. 10-13%) makes it thicker when molten. It needs more pressure to fill thin walls.
If your thin sections are incomplete, check these settings:
| Parameter | A360 Range | Why Different |
|---|---|---|
| Injection speed | 2.5-3.5 m/s | Higher than A383 to push metal into tight spaces |
| Injection pressure | 80-100 MPa | More pressure needed to overcome viscosity |
| Melt temperature | 620-660°C | Higher than A383 to maintain fluidity |
| Die temperature | 200-230°C | Keeps metal liquid longer during fill |
Real example: A manufacturer making water pump housings with 1.2 mm walls saw 25% scrap due to incomplete fill. They increased injection speed from 2.2 m/s to 3.2 m/s and raised die temperature to 215°C. Scrap dropped to 6%.
The Soldering Problem
A360 contains magnesium. Magnesium reacts with steel dies. Over time, the alloy sticks to the die surface. This is called soldering.
Soldering causes:
- Rough part surfaces
- Sticking during ejection
- Die damage
- Shortened tool life
Key fact: Proper lubrication reduces soldering by 80%. Use high-quality water-based graphite. Apply it every cycle. Apply it evenly. Do not skip shots.
Porosity Is Your Enemy
A360's corrosion resistance depends on a dense, uniform structure. Porosity creates pathways for moisture. Water seeps into tiny holes. Rust starts from inside.
In fluid-handling parts, porosity causes leaks. One manufacturer making chemical pump housings failed 40% of pressure tests. X-ray inspection showed porosity throughout. They redesigned vents, added 0.2 mm gaps at the deepest cavities, and increased injection pressure to 90 MPa. Failure rate fell to 5%.
How to Get Consistent Corrosion Resistance?
Start with Pure Material
Corrosion resistance begins with the metal you pour. If your ingots have high copper, your parts will rust.
| Element | Maximum Allowed | What Happens If Too High |
|---|---|---|
| Copper | 0.1% | Above 0.2%, corrosion resistance drops by 30-40% |
| Iron | 0.3% | High iron creates brittle spots that crack |
| Zinc | 0.1% | Excess zinc accelerates pitting corrosion |
Buy from reputable suppliers. Request certificates of analysis. Test incoming material if you run critical parts.
Control Porosity
Porosity is the number one cause of inconsistent corrosion resistance. A part with 2% porosity can fail salt spray tests 3 times faster than a dense part.
How to minimize porosity:
| Action | Target | Why It Helps |
|---|---|---|
| Optimize vents | 0.15-0.2 mm gaps | Lets air escape before metal solidifies |
| Increase injection pressure | 80-100 MPa | Compacts metal, closes voids |
| Slow first phase | 0.2-0.4 m/s | Reduces turbulence that traps air |
| Fast second phase | 2.5-3.5 m/s | Fills die before gas can form |
Add a Protective Coating
Even well-cast A360 benefits from coating. The natural oxide layer is thin (0.01-0.05 μm). A conversion coating adds 2-5 μm of protection.
Common options:
- Chromate conversion: Excellent corrosion resistance. Used in marine and automotive.
- Anodizing: Thicker layer (10-25 μm). Good for wear and corrosion.
- Powder coating: Thickest protection. Best for outdoor hardware.
Real example: An outdoor lighting company used bare A360 for junction boxes. After 18 months, 12% showed rust. They added a chromate conversion coating costing $0.15 per part. Rust dropped to under 1% after 3 years.
What Process Settings Work Best?
Cold-Chamber Parameters
A360 needs precise control. Here is what works:
| Parameter | Target Range | Notes |
|---|---|---|
| Injection speed | 2.5-3.5 m/s | Higher end for thin walls |
| Injection pressure | 80-100 MPa | Maintain pressure until solidification |
| Melt temperature | 620-660°C | Monitor closely; too hot increases porosity |
| Die temperature | 200-230°C | Use thermocouples to verify |
| Lubrication | Every cycle | Water-based graphite, 5-8 mL per shot |
Die Design for A360
Your die must work with A360's lower fluidity:
Draft angles: Use 1.5-2 degrees. This is more than for A383. Extra angle prevents surface damage during ejection.
Venting: Place vents at the end of flow paths. Use 0.15 mm gaps for general areas, 0.2 mm for deep cavities.
Gating: Use larger runners than for A383. Smooth transitions prevent turbulence. Turbulence traps air. Trapped air becomes porosity.
Cooling: Balance cooling rates. Fast cooling (40-60°C/s) creates fine grain structure. But thick sections need slower cooling to prevent cracking.
Post-Casting Steps
Do not skip these steps for corrosion-critical parts:
Shot blasting: Use 80-100 grit media. This removes surface oxides without damaging the metal. Avoid aggressive blasting that can expose subsurface porosity.
Inspection: For fluid-handling parts, use X-ray or ultrasonic testing. This finds internal porosity that leaks during pressure tests.
Coating: Apply conversion coating within 24 hours of casting. Fresh metal oxidizes quickly. A clean surface ensures good coating adhesion.
Where Does A360 Work Best?
Marine Applications
A360 is ideal for parts that see saltwater:
- Boat pump housings
- Valve bodies
- Deck hardware
- Navigation light housings
- Bilge pump components
In marine environments, A360 parts last 5-10 years without significant corrosion. A380 parts typically rust within 2-3 years. Steel parts with paint last 1-2 years before coating fails.
Automotive Fluid Systems
Cars have many parts that touch water, coolant, or road salt:
- Radiator end tanks
- Water pump housings
- Thermostat housings
- Fuel system components
- Brake fluid reservoirs
Real example: An automotive supplier switched radiator end tanks from A380 to A360. The parts cost 8% more upfront. But warranty claims for coolant leaks dropped by 60%. The client saved $200,000 annually on warranty costs.
Industrial Fluid Handling
Chemical plants, food processing, and water treatment need parts that resist corrosion:
- Chemical pump bodies
- Valve housings
- Flow meters
- Pipe fittings
- Filter housings
A360's low copper content also makes it suitable for food contact applications. It does not leach heavy metals into processed food or beverages.
Outdoor Electrical
Electrical components exposed to rain, humidity, or salt:
- Outdoor lighting housings
- Junction boxes
- Solar panel enclosures
- Marine electronics
- EV charging station components
Is A360 Worth the Extra Cost?
Compare A360 vs. A380 vs. A383
| Factor | A360 | A380 | A383 (ADC12) |
|---|---|---|---|
| Corrosion resistance | Excellent | Moderate | Moderate |
| Salt spray hours | 240+ | 96 | 96 |
| Tensile strength | 240-280 MPa | 310-350 MPa | 270-310 MPa |
| Casting fluidity | Good | Very good | Excellent |
| Material cost | Higher | Moderate | Lower |
| Best application | Corrosion-critical | Structural | High-volume, non-critical |
When to Choose A360
Pick A360 when:
- Parts will see moisture, salt, or chemicals
- Failure from rust would cause safety issues or high costs
- You need long service life without maintenance
- Parts must pass salt spray tests (240+ hours)
When to Choose Something Else
Consider A380 or A383 when:
- Parts stay indoors or dry
- Cost is the primary driver
- You need maximum strength (over 280 MPa)
- Complex thin walls (under 1.0 mm) require better fluidity
Conclusion
A360 aluminum offers exceptional corrosion resistance for demanding environments. Its low-copper formula forms a dense oxide layer that blocks moisture, salt, and chemicals. In marine and outdoor applications, it lasts 2-3 times longer than standard alloys.
But A360 requires attention. It does not flow as easily as A383. It needs higher injection pressure and temperature. Porosity is a serious concern—voids create pathways for corrosion. Post-casting coatings add an extra layer of protection.
When you get the process right, A360 delivers. You get parts that resist rust for years. You reduce warranty claims and maintenance costs. You build products that perform in harsh conditions.
The extra effort is worth it. Your customers will notice the difference.
Frequently Asked Questions (FAQ)
Why is my A360 parts' corrosion resistance inconsistent?
Inconsistent resistance usually comes from varying material purity or porosity. Ensure you use high-purity A360 ingots with copper below 0.1%. Minimize porosity by optimizing injection pressure (80-100 MPa) and venting (0.15-0.2 mm gaps). Apply a uniform conversion coating (2-5 μm thick) to ensure the protective oxide layer is consistent across all surfaces.
How does A360 compare to A356 for corrosion resistance?
A360 has better corrosion resistance than A356 due to its lower copper content and optimized magnesium levels. A356 offers higher tensile strength (310 MPa vs. 240-280 MPa) but is more expensive. A360 is better for high-volume, corrosion-critical parts with moderate strength needs. Both outperform A380 in salt spray tests.
Can A360 be used for parts exposed to high temperatures?
A360 performs well up to 120°C but softens above 150°C. For parts exposed to higher heat, consider using A380 for high-temperature sections and A360 for corrosion-prone areas. For continuous exposure above 150°C, a heat-resistant alloy with protective coatings may work better.
Why does my A360 die wear out so fast?
The magnesium content in A360 can cause soldering, where alloy sticks to the die surface. Use high-quality water-based graphite lubrication every cycle. Maintain die temperature at 200-230°C. Consider using coated tool steel (nitrided H13) for longer die life. With proper maintenance, dies should last 300,000 cycles or more.
Can A360 be heat treated to increase strength?
No. A360 does not respond well to heat treatment. Its properties are set during casting. Focus on process control to achieve consistent strength. If you need higher strength with corrosion resistance, consider A356 with protective coating.
Contact Yigu Technology for Custom Manufacturing
At Yigu Technology, we specialize in A360 die casting for clients who need corrosion-resistant parts. We understand this alloy's unique behavior.
We optimize injection pressure and speed to minimize porosity. Our die designs feature enhanced venting and smooth runners to maximize flow. We offer in-house salt spray testing and X-ray inspection for quality assurance. And we apply conversion coatings to boost corrosion resistance for marine or chemical environments.
Whether you need marine hardware, automotive fluid components, or industrial valve bodies, we help you get the most from A360. Contact us to discuss your project. Let us build parts that last.
