Material Name : GD-AlSi17Cu4Mg
Material Identification & Standards
GD‑AlSi17Cu4Mg is a high-silicon, copper-modified aluminum casting alloy with enhanced strength and thermal durability. Equivalent designations include:
- JIS (Japan): ADC14
- AA (USA): A390.0
- BS (UK): LM30 (BS 1490)
- DIN (Germany): AlSi17Cu4Mg (DIN 1725-2)
- ISO (International): AlSi17Cu4Mg
- EN (Europe): EN AC‑48100 (EN 1706)
- Common Use Type: High-silicon aluminum die casting alloy
BS（UK）: No exact equivalent; LM30 (BS 1490) may be considered a near match
EN 1706 is a standard designation, officially titled:
EN 1706: Aluminium and aluminium alloys — Castings — Chemical composition and mechanical properties.
It is a European Standard (EN) that specifies the chemical composition and mechanical properties of cast aluminum alloys.
Therefore, all European cast aluminum alloys, such as EN AC‑44300, EN AC‑44100, EN AC‑43000, etc., are defined and governed under the framework of EN 1706.
Chemical Composition
- Silicon (Si): 16.0 – 18.0%
- Copper (Cu): 2.0 – 5.0%
- Magnesium (Mg): 0.3 – 0.6%
- Iron (Fe): ≤ 1.3%
- Manganese (Mn): ≤ 0.5%
- Zinc (Zn): ≤ 1.0%
- Nickel (Ni): ≤ 0.5%
- Others (including Sn, Pb, Ti, etc.): ≤ 0.5%
- Aluminum (Al): Balance
Mechanical & Physical Properties
| Property | Typical Value Range |
| Tensile Strength | ~280 – 320 MPa |
| Yield Strength | ~190 – 240 MPa |
| Elongation | ~1 – 3% |
| Brinell Hardness | ~100 – 120 HB |
| Density | ~2.7 – 2.8 g/cm³ |
| Melting Temperature | ~510 – 580 °C |
Thermal & Electrical Properties
| Property | Typical Value Range |
| Thermal Conductivity | ~110 – 130 W/m·K |
| Electrical Conductivity | ~20 – 25 % IACS (11 – 14 MS/m) |
| Thermal Expansion Coefficient | ~19 – 21 µm/m·K |
Pros & Cons Summary
| Feature | Pros | Cons |
| Strength & Hardness | Very high surface hardness (~120 HB), good strength (~320 MPa) | Low ductility (~1–2%) |
| Heat Resistance | Excellent at high operating temperatures | Slight risk of thermal cracking |
| Castability | Good flowability for complex shapes | Susceptible to porosity |
| Wear Resistance | Excellent wear resistance due to high Si | Machinability requires hard tooling |
Castability & Corrosion Resistance
GD-AlSi17Cu4Mg offers excellent castability due to its high silicon content, which promotes fluidity and minimizes shrinkage. However, due to the high hardness and silicon particle content, it is susceptible to microcracking if cooling rates are not optimized. Proper gating design and die temperature control are critical.
Its corrosion resistance is moderate; the presence of copper may reduce corrosion tolerance in marine or humid environments unless protective coatings are applied. For internal engine parts or sealed housings, its corrosion stability is acceptable.
Key Characteristics
- High silicon content (~17%) provides superior wear resistance
- High copper (~4%) and magnesium improve strength and thermal stability
- Excellent surface hardness (~100–120 HB)
- Low elongation, not suitable for high-deformation parts
- Good thermal performance; usable in heat-exposed components
- Recommended for parts needing dimensional stability and thermal cycling endurance
Common Applications
- Automotive Engine Parts: Cylinder heads, pistons, transmission casings
- Industrial Machinery: Gear housings, pump bodies, brake components
- Electronics & Thermal Equipment: Heat sinks, enclosures, structural components in hot zones
- Powertrain Components: Timing chain housings, turbocharger structures
Conclusion & Recommendation
GD‑AlSi17Cu4Mg is a premium high-silicon aluminum alloy tailored for applications requiring hardness, dimensional accuracy, and thermal strength. Ideal for high-load, high-temperature, or wear-prone environments such as engine and transmission components. However, machinability may require diamond or carbide tooling, and porosity control during casting is essential.
If your design demands high hardness, strength, and durability under thermal stress, GD-AlSi17Cu4Mg is a highly recommended alloy. For corrosion-critical environments, post-processing protection (anodizing, coating) is advised.