This article explores Zamak 2’s composition, mechanical properties, key benefits, and ideal applications. Whether you’re designing tooling or prototyping a new product, understanding Zamak 2’s unique features can help you make better material choices.
Elemental Composition
Zinc (Zn)
Zamak 2 contains about 93–95% zinc, which provides excellent casting fluidity, solidifies with minimal shrinkage, and ensures high dimensional accuracy.
Aluminum (Al)
Roughly 4% aluminum increases strength and casting performance. It enhances flow characteristics, improves surface finish, and adds a base level of corrosion resistance.
Copper (Cu)
With 2.5–3% copper, the alloy gains significantly in hardness, creep resistance, and wear performance.
This addition is key to Zamak 2’s mechanical superiority over other Zamak alloys.
Trace Elements
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Magnesium (Mg): 0.02–0.05% to strengthen grain boundaries and improve corrosion behavior.
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Iron (Fe): 0.005–0.01% helps control the microstructure. However, excessive iron can cause casting defects, so it must be precisely managed.
Mechanical and Physical Properties
Mechanical Properties
Among all Zamak alloys, Zamak 2 offers the highest mechanical strength. It performs well under long-term static loads and suits demanding structural or tooling applications.
Typical properties in the as-cast condition include:
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Tensile Strength: 410–420 MPa
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Yield Strength: 325–335 MPa
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Elongation: 2.5–3.5%
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Hardness: 115–125 HB
Physical Properties
Zamak 2 offers excellent physical stability, with low shrinkage and strong dimensional consistency.
Its good thermal performance and controlled melting behavior help ensure uniform cooling, minimizing distortion and improving casting precision.
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Density: 6.6–6.8 g/cm³
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Melting Range: 380–390°C
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Thermal Conductivity: 100–120 W/m·K
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Linear Shrinkage: 0.4–0.6%
Main Benefits of Zamak 2
Superior Strength
Zamak 2 offers unmatched strength and hardness due to its copper content.
It’s ideal for static-load components that require structural integrity, such as molds, tooling, and rigid parts.
Excellent Wear Resistance
Copper enhances wear performance, allowing the alloy to endure prolonged friction and surface contact. It can maintain surface quality even after extended use.
Easy Machinability
Zamak 2 is well-suited for high-speed machining operations like drilling, tapping, and milling.
It causes minimal tool wear and ensures consistent output, especially valuable in prototyping and precision manufacturing.
Tight Dimensional Control
Its low shrinkage and excellent fluidity lead to precise, repeatable castings.
Aluminum helps stabilize the solidification process, reducing distortion and ensuring part consistency across batches.
Surface Treatment Compatibility
Zamak 2’s fine grain and dense surface make it ideal for coatings such as electroplating, powder coating, and painting.
These treatments not only improve corrosion resistance but also enhance appearance and texture.
Limitations of Zamak 2
Limited Ductility
With higher hardness comes reduced flexibility. Zamak 2 has low ductility and is not ideal for parts exposed to impact, vibration, or bending.
Aging Over Time
The copper content can lead to gradual hardening and slight dimensional shifts.
This may affect applications requiring long-term dimensional precision.
Moderate Corrosion Resistance
While aluminum adds some protection, the zinc-rich base remains vulnerable in harsh environments.
Without surface treatment, it may rust or discolor in moisture or salt-laden air.
Compatible Manufacturing Processes
Casting
Die Casting (Hot Chamber)
This is the most common method for Zamak 2. It supports rapid production, excellent surface finish, and consistent dimensions.
Ideal for mid-to-high volume production of molds, fixtures, and structural parts.
Gravity Casting
Zamak 2 is also suitable for gravity casting, which is a practical choice for small batches or large-sized components.
While it may offer slightly lower precision than die casting, it’s still effective for moderate-precision parts.
Post-Processing
Fine Machining
Zamak 2 handles finishing processes well. It allows for precise operations like trimming, drilling, chamfering, and engraving.
The alloy’s moderate hardness and stable machining characteristics increase production efficiency and flexibility.
Surface Finishing
The alloy accepts a variety of finishes. From decorative chrome and nickel plating to functional powder coating or painting, Zamak 2 can be tailored to meet both technical and aesthetic requirements.
Typical Applications of Zamak 2
Molds and Tooling
Kirksite Molds
Perfect for sheet metal stretching, bending, and forming tools. Zamak 2’s hardness and stability make it reliable under repetitive mechanical stress.
Prototype Molds
Great for testing product designs before committing to steel molds. It’s fast to cast and easy to modify, saving time and cost in development cycles.
Fixtures and Measuring Tools
Auxiliary Fixtures
Positioning fixtures are used in welding, machining, and assembly processes. Zamak 2 resists deformation and helps maintain precision in positioning.
Inspection Tools
Its dimensional stability and machinability make it ideal for measurement tools like gauges, alignment blocks, and calibration fixtures.
Industrial Components
Automotive
Used for brackets, housings, and connectors during prototype stages. It balances form and function, meeting appearance and accuracy demands.
Aerospace
Used for non-critical brackets, mounts, and internal structures. Its dimensional reliability and ease of machining suit aerospace parts with moderate strength requirements.
Electronics
Zamak 2 is used in casings, mounting frames, and hardware components. The fine surface finish supports decorative coatings and tight assembly requirements.
Comparison with Other Zamak Alloys
Zamak 2 vs Zamak 3
Zamak 2 is stronger and harder, better for parts that can withstand static loads. Zamak 3 is more ductile and suited for parts under dynamic or bending loads.
Zamak 2 vs Zamak 5
Zamak 2 offers higher dimensional accuracy and wear resistance. Zamak 5 has better corrosion resistance and is more versatile for general applications.
Zamak 2 vs Zamak 7
Zamak 2 lasts longer in tooling applications. Zamak 7 has superior flow characteristics, ideal for detailed or thin-walled castings.
When to Choose Zamak 2
Ideal uses for Zamak 2:
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Parts that require extreme mechanical strength and rigidity.
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Molds, jigs, and fixtures that must retain their shape.
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Short-cycle injection molds for transitional development phases.
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Parts that require strict dimensional accuracy and close tolerances.
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Parts that require multiple machining, modification, or surface treatments.
Where Zamak 2 is not suitable:
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Parts that are subject to bending, impact, or deformation.
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Extremely corrosive environments (without surface treatment).
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Assembly parts that require extremely long-term micro-dimensional accuracy.
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Dynamic parts that require more ductile, cost-effective alloys.
Conclusion
Zamak 2 stands out in mold making, fixture design, and structural components that demand mechanical strength, stability, and precise machining.
While it may have limitations in ductility and corrosion resistance, its advantages in strength and wear resistance make it an excellent choice for applications subject to static loads.
At CEX Casting, we specialize in aluminum and zinc alloy die casting solutions.
With advanced technology and professional experience, we are committed to supporting your Zamak 2 project from mold design to final production.
Contact us today to see how Zamak 2 alloy can elevate your next project.