Zamak 5 is a zinc-based die casting alloy that contains aluminum and copper. It’s known for its impressive strength, excellent casting performance, and smooth surface finish. With high dimensional stability, strong wear resistance, and moderate corrosion resistance, Zamak 5 is widely used across the automotive, electronics, and consumer goods industries to manufacture complex, durable, and precision-engineered parts.
This article outlines the chemical composition, mechanical and physical properties, processing benefits, surface treatment options, and typical application scenarios of Zamak 5. Read on to determine if it’s the right material for your next project.
Main Elemental Composition
Zinc (Zn)
The primary element of Zamak 5, accounts for about 95%, providing strength and stability while maintaining low production costs.
Aluminum (Al)
Zamak 5 contains 3.8–4.3% aluminum, which significantly enhances the alloy’s strength and fluidity, allowing for finer castings with improved performance in complex shapes.
Copper (Cu)
Copper, present at 0.75–1.25%, increases the tensile strength and wear resistance of Zamak 5, although it slightly reduces its corrosion resistance, making it ideal for durable, high-stress applications.
Magnesium (Mg)
Magnesium, up to 0.06%, refines the grain structure of Zamak 5, improving both its corrosion resistance and surface quality, which is essential for applications exposed to harsh conditions.
Iron (Fe)
Iron is maintained at a trace level of ≤0.075% to avoid brittleness and minimize casting issues such as shrinkage and porosity, ensuring the consistency and integrity of the final product.
Mechanical and Physical Properties
Mechanical Properties
Zamak 5 delivers strong mechanical performance in its cast state. Below are the typical mechanical properties under standard die casting conditions.
Variations may occur based on mold design, cooling rate, and casting dimensions.
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Tensile Strength: 320–340 MPa
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Yield Strength: 270–290 MPa
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Hardness: 80–85 HB
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Elongation: 6–8%
Physical Properties
The alloy’s physical properties support efficient processing and long-term stability.
Its medium density keeps parts structurally balanced. The relatively low melting point reduces energy use.
Excellent thermal conductivity and specific heat capacity enhance performance in electronics.
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Density: 6.5–6.7 g/cm³
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Melting Point: 380–390°C
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Thermal Conductivity: 110–115 W/m·K
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Specific Heat Capacity: 380–400 J/kg·K
Advantages in Die Casting and Machining
Excellent Fluidity: Thanks to its aluminum content and optimized composition, Zamak 5 flows smoothly into intricate mold features, making it suitable for parts with complex shapes and thin walls.
Fast Cycle Time: Its low melting point allows for rapid solidification during casting, which shortens cycle times and increases production efficiency.
Dimensional Stability: The alloy’s controlled solidification behavior and low shrinkage rate help maintain tight tolerances and part consistency.
Smooth As-Cast Surface: The fine grain structure formed during solidification produces a naturally smooth surface, reducing the need for post-casting treatments.
Thermal Fatigue Resistance: Its thermal properties allow the alloy to endure repeated heating and cooling without degrading the mold, extending mold life.
Good Machinability: The balanced alloy composition ensures stable cutting performance and reduces wear on machining tools during drilling, tapping, or turning.
Corrosion Resistance Condition
Zamak 5 provides moderate inherent corrosion resistance, suitable for dry indoor or controlled settings.
Compared to Zamak 3, its higher copper content slightly reduces corrosion resistance when untreated.
For outdoor or high-humidity environments, surface treatments like electroplating, powder coating, or passivation are recommended.
With the right finish, Zamak 5 components can remain stable and functional for years in demanding conditions.
Surface Treatment Options
Electroplating
● Chrome or Nickel Plating: Improves corrosion resistance while creating a smooth, reflective finish that balances durability with visual appeal.
● Zinc Plating: Offers reliable protection against oxidation, making it suitable for industrial parts that also require a clean and uniform appearance.
Powder Coating
Forms a consistent, durable outer layer that resists scratches, corrosion, and UV exposure, while also providing a matte or textured finish for visual consistency.
Spray Painting
Ideal for products with branding, color matching, or custom design requirements.
Proper pre-treatment, such as degreasing, sandblasting, and chemical passivation, offers stronger painting adhesion for Zamak 5.
Polishing
Forms a bright, mirror-like surface that enhances both the look and the perceived quality of decorative or visible components.
Comparison with Other Zamak Alloys
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Zamak 3: Best flowability and castability, high ductility, but lower strength.
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Zamak 5: Better strength and wear resistance, slightly reduced ductility and flowability.
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Zamak 7: Superior to Zamak 3 in fluidity and ductility, but lacks the strength needed for structural parts.
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Zamak 2: Offers the highest strength and hardness, but has poor ductility, higher cost, and limited usage.
Global Standards & Grades
Zamak 5 is known by different designations in various international standards：
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International Standard: ISO ZnAl4Cu1
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European Standard: DIN ZL0410
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British Standard: ZnAl4Cu1
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Japanese Standard: ACuZinc5
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Chinese Standard: ZnAl4Cu1
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American Standard: ASTM B86 / B240
Application Scenarios
Automotive Industry
Used in parts like door handles, brackets, gear housings, and decorative trims. Combines mechanical strength with strong surface finish compatibility.
Consumer Hardware
Ideal for locks, hinges, knobs, zippers, and other consumer hardware. Balancing durability with visual appeal for high-frequency use.
Electronic Products
Applied in housings, connectors, and interface components. Excellent thermal conductivity and dimensional stability protect sensitive electronics.
Industrial Equipment
Perfect for zinc die casting components such as brackets, fixtures, and connectors. Maintains performance under dynamic loads and continuous use.
Furniture and Décor
Supports high-end design in fasteners, handles, and decorative elements. Allows precise shaping and a polished look for custom furniture.
Environmental Benefits
Zamak 5 is fully recyclable and retains its mechanical and surface properties after multiple melt cycles.
Its low melting point reduces energy use during casting, lowering carbon emissions per part.
Reusing offcuts and scraps minimizes raw material waste and supports circular economy goals.
Compared to aluminum or steel casting, Zamak 5 leaves a smaller carbon footprint, which is an ideal option for eco-conscious manufacturing.
Design Flexibility and Cost Advantages
Zamak 5 allows the creation of complex, thin-walled designs with precise details and tight tolerances.
Its good casting performance allows multiple functional parts to be integrated into a single casting, streamlining assembly and improving structural consistency.
In the medium to high-volume production, its fast cycle times, low defect rates, and minimal finishing needs reduce per-unit costs.
Zamak 5 causes lower wear on die casting molds than aluminum and magnesium alloys, resulting in longer mold lifespans and lower maintenance and replacement costs.
Conclusion
Zamak 5 combines strength, castability, and surface finish versatility.
It is ideal for both structural and decorative components, from automotive to electronics, and it delivers reliable performance and excellent aesthetics.
CEX Casting offers patented technologies and full-process manufacturing solutions.
We specialize in custom end-to-end zinc and aluminum die casting solutions for global clients.
Contact us today to discover how CEX Casting can bring your next project to reality.