Aluminum 356.0 vs. A356.0 in Sand Cast F Condition: Detailed Comparison
When choosing between Aluminum 356.0 and A356.0 for sand casting in the F (as-fabricated) condition, the subtle yet impactful differences between the alloys must be understood. This article compares their composition, mechanical properties, and practical implications, helping you make an informed decision.
Overview of Designation and Standards
Property
356.0
A356.0
Designation
356.0 (Aluminum Association)
A356.0 (Aluminum Association)
UNS Number
A03560
A13560
EN Number
EN AC-42000 / EN AC-Al Si7Mg
EN AC-42000 / EN AC-Al Si7Mg
Aluminum 356.0 vs. A356.0 in Sand Cast F Condition
Chemical Composition
This table highlights differences in alloying elements and impurities between 356.0 and A356.0, which significantly influence their performance and application.
Element
356.0 (wt%)
A356.0 (wt%)
Key Effect
Aluminum (Al)
90.1–93.3
91.1–93.2
Higher Al in A356.0 reduces intermetallic formation.
Silicon (Si)
6.5–7.5
6.5–7.5
Enhances castability and wear resistance.
Magnesium (Mg)
0.2–0.45
0.25–0.45
Higher minimum Mg in A356.0 improves strength.
Iron (Fe)
≤0.6
≤0.2
Lower Fe in A356.0 minimizes brittle intermetallic phases.
Copper (Cu)
≤0.25
≤0.2
Lower Cu in A356.0 enhances corrosion resistance.
Manganese (Mn)
≤0.35
≤0.1
Tighter Mn control improves ductility in A356.0.
Zinc (Zn)
≤0.35
≤0.1
Reduced Zn improves homogeneity in A356.0.
Titanium (Ti)
≤0.25
≤0.2
Slightly tighter control in A356.0.
Aluminum 356.0 vs. A356.0 in Sand Cast F Condition
Mechanical Properties
Property
356.0
A356.0
Impact
Yield Strength (MPa)
118–130
81.5–83.6
356.0 has higher yield strength but lower fatigue resistance.
Tensile Strength (MPa)
164–180
150–163
A356.0 is slightly weaker but more consistent.
Elongation (% strain)
6–7.2
6–7.2
Both alloys exhibit similar ductility.
Hardness (HV)
86–96
66–73
Higher impurities in 356.0 result in greater hardness.
Fatigue Strength (MPa)
98.9–111
100–116
A356.0 outperforms 356.0 in fatigue resistance.
Aluminum 356.0 vs. A356.0 in Sand Cast F Condition
Similar performance for heat transfer applications.
Thermal Expansion Coefficient (µstrain/°C)
20.6–22.4
20.7–22.4
Negligible differences in thermal expansion.
Aluminum 356.0 vs. A356.0 in Sand Cast F Condition
Intermetallic Phases and Impurity Effects
Iron (Fe):
356.0: High Fe content increases Al-Si-Fe phases (e.g., β-Al5FeSi), leading to brittleness and reduced fatigue life.
A356.0: Lower Fe minimizes these brittle phases, ensuring better ductility and strength.
Magnesium (Mg):
Higher Mg content in A356.0 enhances the precipitation of Mg2Si during cooling, improving strength and hardness.
Copper (Cu):
Lower Cu in A356.0 reduces galvanic corrosion, making it suitable for marine and humid environments.
Applications
Industry
356.0
A356.0
Automotive
Wheels, non-critical structural parts
Suspension and fatigue-critical parts
Aerospace
Non-critical castings
Structural castings with fatigue demands
Marine
General-purpose hardware
Corrosion-resistant fittings
Electronics
Enclosures and non-precision parts
High-precision enclosures
Aluminum 356.0 vs. A356.0 in Sand Cast F Condition
Key Takeaways
356.0: Suitable for applications where higher strength and hardness are required but fatigue resistance is not critical.
A356.0: Preferred for dynamic or corrosive environments due to its superior fatigue resistance and tighter impurity control.
Conclusion
When selecting between 356.0 and A356.0 for sand casting in the F condition, the decision hinges on application-specific requirements. A356.0 excels in fatigue resistance, corrosion resistance, and consistency, while 356.0 is suitable for applications prioritizing higher strength over cyclic performance. Both alloys are versatile choices for automotive, aerospace, and industrial applications, but A356.0 remains the go-to material for high-stress and corrosion-prone environments.
