A383 Aluminum Die Casting | A380 Alternative

A383 (ADC12's closest Western relative) modifies the A380 recipe with higher silicon (10.5%) and lower copper (2.5%). The result: measurably better die-fill in thin walls and intricate features, with slightly better pressure tightness - while keeping the strength, iron content, and tooling friendliness that make A380 the HPDC default.

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A383 Chemical Composition

Element	A383	A380 (for comparison)
Silicon (Si)	9.5 to 11.5%	7.5 to 9.5%
Copper (Cu)	2.0 to 3.0%	3.0 to 4.0%
Iron (Fe)	1.3% max	0.6 to 1.0%
Magnesium (Mg)	0.10% max	0.10% max
Zinc (Zn)	3.0% max	3.0% max
Aluminum (Al)	Balance	Balance

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Mechanical Properties

Property	A383	A380
Tensile strength	310 MPa	320 MPa
Yield strength	150 MPa	160 MPa
Elongation	3.5%	3.5%
Hardness	75 to 80 HB	80 HB
Fluidity (spiral test)	Best of the 3xx HPDC alloys	Baseline
Pressure tightness	Better	Good

Strength is marginally lower than A380 - in practice the difference is inside drawing tolerance for most housings and brackets.

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When to Specify A383 Over A380

Design situation	Recommendation
Walls at or below 1.5 mm with long flow lengths	A383
Dense fin fields (heat sinks, LED housings)	A383
Fine ribs, bosses, text, or cosmetic as-cast surfaces	A383
Leak-tight housings (fuel, hydraulic, pneumatic)	A383 preferred
Standard housings above 2 mm walls	A380 - cheaper and slightly stronger
Maximum as-cast strength	A380

A383 costs marginally more per kilogram and is stocked slightly less widely than A380; for programs that do not stress die-fill limits, A380 remains the economical default.

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A383 and ADC12

A383 and ADC12 overlap heavily - ADC12 (JIS H5302) allows a slightly wider silicon and copper window. On drawings, specifying "A383 or ADC12" is common practice for Asia-sourced programs. KastMfg casts both daily and certifies chemistry per batch with spectrometer records. See ADC12 vs A380 for the full three-way comparison.

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Processing Notes

• Casting temperature: standard HPDC aluminum practice (around 650°C shot temperature) - the higher silicon widens the fill window at the low end
• Die temperature: standard 180 to 250°C HPDC practice
• Machining: same as A380; slightly more abrasive on inserts due to silicon
• Finishing: powder coat, e-coat, and chromate all standard; decorative anodizing not recommended (high silicon grays the finish)

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Applications

• Thin-wall electronics enclosures and 5G housings
• Heat sinks and LED flood light housings with dense fins
• Leak-tight pump, valve, and compressor bodies
• Small intricate hardware where A380 short-shots
• Cosmetic as-cast panels and bezels

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Frequently Asked Questions

Is A383 stronger than A380?

No - A380 holds a small strength edge (320 vs 310 MPa tensile). A383's advantages are fillability and pressure tightness, not strength.

Can A383 be anodized?

It can be, but the 10%+ silicon produces a gray, non-uniform decorative finish. For anodized cosmetics, choose a low-silicon alloy or plan for powder coating instead.

Is A383 available for low-volume runs?

Yes. Because A383 and ADC12 are near-interchangeable, KastMfg can often run A383-specified parts from ADC12 melt stock after customer approval, which keeps low-volume die casting programs economical.

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Related Materials

• die casting materials - full alloy selection guide
• A380 aluminum die casting - the HPDC default
• A360 aluminum die casting - higher corrosion resistance option
• aluminum die casting - KastMfg HPDC capability

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A383 inquiry: yaoqingpu1983@gmail.com | +86 138 1403 4409 | No.6, Rungu Road, Nanjing, China