AlSi9Mg is a casting aluminum alloy classified according to ISO standards. The alloy is known as A360 in the United States and EN AC-43300 in Europe. One of its main features is the relatively high silicon content, which improves fluidity and is therefore particularly suitable for casting applications. It is typically used for sand casting, but can also be used in squeeze casting processes. AlSi9Mg can also be heat treated to further improve its mechanical properties, making it an ideal material for parts that require excellent strength and reliability.
This article will take an in-depth look at why AlSi9Mg is highly favored by manufacturers, studying its composition, mechanical properties, and key benefits.
We will also explore this alloy’s heat treatment capabilities and compare its performance to other aluminum alloys.
Keep reading to get a better understanding of this multifunctional alloy and learn how it can help elevate your next project.
AlSi9Mg Aluminum Composition
|
Elemental Composition |
Values |
|
Aluminum (Al) |
88 – 90% |
|
Silicon (Si) |
9% |
|
Magnesium (Mg) |
0.3 – 0.5% |
|
Iron (Fe) |
≤0.15% |
| Copper (Cu) |
≤0.10% |
| Zinc (Zn) |
≤0.10% |
| Manganese (Mn) |
≤0.10% |
| Titanium (Ti) |
≤0.20% |
AlSi9Mg Aluminum Mechanical Properties
The following table shows the mechanical properties of AlSi9Mg in its raw material state. Key properties include:
|
Mechanical Properties |
Values |
|
Tensile Strength |
180 – 250 MPa |
|
Yield Strength |
130 – 210 MPa |
| Elongation |
5 – 10% |
| Hardness |
60 – 80 HB |
AlSi9Mg Aluminum Advantages
The characteristics of AlSi9Mg come with significant advantages, which can meet the industry demand for high-performance and high-precision castings.
It combines reliability, adaptability, and strength, making it a go-to choice for complex applications.
Exceptional Castability
The high silicon content in AlSi9Mg can significantly improve its flowability during casting, enabling the alloy to accurately fill the mold.
This reduces casting defects and enables the production of complex castings with fine details.
Heat Treatability
The magnesium content of AlSi9Mg makes it highly responsive to heat treatment and can be used to alter its mechanical properties.
This enables manufacturers to improve their strength, hardness, and overall performance according to specific application requirements.
Corrosion Resistance
The high aluminum content gives AlSi9Mg strong natural corrosion resistance.
This characteristic is particularly important for components exposed to moisture, chemicals, or other harsh environmental conditions.
Corrosion resistance helps extend the service life of components, reduce maintenance requirements, and ensure long-term reliability.
AlSi9Mg Aluminum Applications
AlSi9Mg combines castability, strength, and corrosion resistance, ensuring reliable performance in fields that require high precision and durability.
Automotive Industry
AlSi9Mg is used to manufacture important automotive parts such as engine components and complex housings.
Aerospace
In the aerospace field, AlSi9Mg is highly suitable for structural components that need to withstand significant mechanical loads while maintaining the lowest possible weight, such as aviation brackets and support structures.
Industrial Equipment
AlSi9Mg can be used to produce durable and wear-resistant components such as gearbox housings, pump housings, and mechanical brackets.
High strength and castability enable it to withstand high mechanical stress during continuous operation, ensuring long-lasting and efficient equipment performance.
Consumer Electronics
AlSi9Mg can produce castings that are both lightweight and sturdy, making it an excellent choice for electronic device components such as device casings, camera bodies, heat sinks, and light housings.
AlSi9Mg Aluminum vs. A356 Aluminum
Both AlSi9Mg and A356 are commonly used cast aluminum alloys, but they have different advantages and application areas.
AlSi9Mg is known for its excellent fluidity due to its higher silicon content, but comes with lower mechanical strength compared to A356, making it more suitable for applications where castability and fluidity are critical but mechanical strength is not highly required, such as engine parts and complex-shaped castings in the automotive industry.
On the other hand, A356 comes with a lower silicon content compared to AlSi9Mg but has higher mechanical strength, especially after heat treatment, making it the preferred material for applications that require higher tensile strength and yield strength, including heavy automotive, marine, and aerospace components.
Table 1: Elemental Composition Comparison
|
Element |
AlSi9Mg Aluminum (%) | A356 Aluminum (%) |
|
Aluminum (Al) |
88 – 90 | 91.1 – 93.3 |
|
Silicon (Si) |
9.0 | 6.5 – 7.5 |
|
Magnesium (Mg) |
0.3 – 0.5 | 0.2 – 0.45 |
|
Copper (Cu) |
≤ 0.10 |
≤0.2 |
| Zinc (Zn) | ≤ 0.10 |
≤0.1 |
| Iron (Fe) | ≤ 0.15 |
≤0.2 |
| Manganese (Mn) | ≤ 0.10 |
≤0.1 |
| Titanium (Ti) | ≤ 0.20 |
≤0.2 |
Table 2: Mechanical Properties Comparison
|
Property |
AlSi9Mg Aluminum | A356 Aluminum |
|
Tensile Strength (MPa) |
180 – 250 | 207 – 310 |
|
Yield Strength (MPa) |
130 – 210 |
138 – 228 |
| Elongation (%) | 5 – 10 |
3 – 10 |
| Hardness (HB) | 60 – 80 |
70 – 80 |
Table 3: Physical and Chemical Properties Comparison
|
Property |
AlSi9Mg Aluminum | A356 Aluminum |
|
Density (g/cm³) |
2.68 | 2.68 |
|
Melting Point (°C) |
570 – 595 | 570 – 580 |
|
Electrical Conductivity (% IACS) |
35 |
33 – 36 |
| Coefficient of Thermal Expansion (10^-6 /°C) | 21 |
21.4 |
| Thermal Conductivity (W/m·K) | 150 – 170 |
151 |
| Corrosion Resistance | Good |
Good |
Table 4: Applications Comparison
|
Application Fields |
AlSi9Mg Aluminum | A356 Aluminum |
|
Automotive Industry |
engine components, cylinder heads, transmission housings, brackets | engine blocks, cylinder heads, structural parts |
|
Aerospace |
brackets, lightweight frames, housings, gear casings |
landing gear components, turbine housings, helicopter rotor hubs |
| Industrial Equipment | gearboxes, pump casings, motor housings, valve bodies |
pump housings, valve bodies, gearbox housings, brackets, heat exchangers |
| Consumer Electronics | device casings, camera bodies, heat sinks, light housings |
enclosures, housings, heat sinks, battery cases |
Can AlSi9Mg Aluminum Be Heat Treated?
Yes, AlSi9Mg aluminum can undergo heat treatment to improve its mechanical properties.
For sand casting, T4 and T6 heat treatment are usually used. T4 can enhance ductility and achieve moderate strength, while T6 can improve strength and hardness to meet the requirements of demanding applications.
For squeeze casting, T6 heat treatment is preferred because rapid cooling during the squeeze casting process can achieve finer microstructures, while T6 heat treatment can further improve the strength and durability of castings.
What Is AlSi9Mg Aluminum Equivalent to?
|
ISO Standard (International) |
GB Standard (China) | UNS ASTM (The US) | ANSI (The US) | JIS Standard (Japan) | EN Standard (Europe) | BS Standard (UK) | DIN Standard (Germany) |
| AlSi9Mg | ZL104 | A360.0 | 360.0 | AC4A | EN AC-43300 | LM9 |
G-AlSi9Mg |
Why AlSi9Mg Aluminum Is Suitable for Squeeze Casting?
The composition of AlSi9Mg makes it particularly suitable for squeeze casting.
The high silicon content in AlSi9Mg can promote good fluidity, allowing the alloy to fill complex molds without defects.
During the squeeze casting process, AlSi9Mg also exhibits excellent dimensional stability.
Due to the low expansion coefficient of aluminum-silicon alloy, there is minimal shrinkage during cooling, which can reduce defects and facilitate heat treatment.
In addition, AlSi9Mg also comes with good thermal conductivity, which can quickly dissipate heat and maintain a uniform cooling rate during the squeeze casting process.
The faster cooling rate accelerates the solidification of the molten metal, reduces the formation of hot cracks, and ensures a smooth surface and uniform structure.
CEX Squeeze Casting Equipment
AlSi9Mg Aluminum Squeeze Casting by CEX Casting
Cases
At CEX Casting, we use advanced squeeze casting technology combined with T6 heat treatment to specialize in producing high-quality AlSi9Mg aluminum components with excellent mechanical properties, minimal porosity, and outstanding heat resistance.
We have successfully manufactured various AlSi9Mg castings, including engine mount and steering knuckle for the automotive industry; pump housing and valve body for industrial machinery.
Our squeeze casting process ensures the lightweight, durability, and precision of parts to meet the strict requirements of various industries.
Mechanical Properties
Through CEX’s Advanced squeeze casting process combined with T6 heat treatment, the AlSi9Mg aluminum has achieved significant improvement in mechanical properties:
Conclusion
AlSi9Mg aluminum achieves a perfect balance in strength, castability, and heat treatment, making it an ideal choice for industries such as automotive, aerospace, and industrial equipment.
Its excellent performance in complex and high-stress applications makes it the main material for producing precision and high-performance castings.
Contact us today to learn how our expertise in AlSi9Mg aluminum and squeeze casting technology can help you achieve your next project.