Zinc Alloys Die Casting
Zinc-based alloys are the easiest to die cast. High ductility and excellent impact strength make these alloys suitable for a variety of products. Zinc die castings can provide thin walls and excellent surface smoothness, easily for electroplating and spraying relatively.
Zinc Alloy Characteristics
- High strength and hardness
- Excellent conductivity
- High thermal conductivity
- Low-cost raw materials
- High dimensional accuracy and stability
- Excellent thin wall capability
- Can be cold-formed, easy to connect
- High-quality finishing features
- Excellent corrosion resistance
- Fully recyclable
Zinc alloy 2, also known as Zamak 2 (ASTM AC43A), is the highest strength and hardness in the Zamak alloy series. This alloy has excellent casting characteristics, including:
- Higher creep performance than other Zamak alloys.
- Compared with aluminum die-casting alloy, it has excellent damping ability and damping effect.
- High strength and hardness after long-term aging.
Zamak 3 (ASTM AG40A) or Zinc Alloy 3 is the most widely used in North America. For many reasons, it is usually the first choice when considering zinc alloy die casting.
- The ideal balance for physical and mechanical capacities.
- Excellent castability and long-term dimensional stability.
- Electroplating, painting, and chromate treatment have excellent surface treatment characteristics.
- Compared with aluminum die casting alloy, it has excellent damping ability and damping effect.
Zamak 5 (ASTM AC41A) or zinc alloy 5 is the most widely used zinc alloy in Europe.
- It has a higher copper content than Zamak 3, so it is stronger.
- Its ductility (decrease in elongation) is lower than Zamak 3.
- The designer must remember that the decrease in ductility will affect the formability during secondary processing (such as bending, riveting, forging, or crimping operations).
- Due to the wide availability of Zamak 3, component engineers usually enhance components through design modifications rather than using Zamak 5.
- When it is necessary to measure tensile properties, Zamak 5 castings are recommended.
- Compared with alloy 3, Zamak 5 is easier to plate, finish, and machine.
Zamak 7 (ASTM AG40B) or zinc alloy 7 is an improved form of Zamak 3. It is a high-purity alloy with lower magnesium content and stricter impurity specifications. This can improve the fluidity, ductility, and surface finish of the casting.
Zamak 7 is mainly for special hardware applications, or when castings require additional formability during subsequent assembly processes such as crimping or riveting. Its higher fluidity also allows thinner walls casting.
- Sometimes higher fluidity is required, especially on zinc die casting parts with complex details.
- To avoid casting parts’ excessive flash, it is necessary to have good mold compatibility and strictly control the casting process parameters.
- The high ductility exhibited also affects processing, but it is mainly to remove and trim flash during secondary processing.
- Compared with aluminum die casting alloy, Zamak 7 has excellent damping ability and vibration attenuation.
ZA-8 or zinc-aluminum alloy contains more aluminum alloy than Zamak combination gold. ZA-8 contains about 8.4% aluminum and is the only ZA alloy that can be die-casted in a hot chamber. This is an important consideration when selecting component materials.
- ZA-8 has excellent surface treatment and electroplating properties and was developed as a permanent mold alloy.
- Although its casting characteristics are not as good as other zinc alloys, it can significantly improve strength, hardness, and creep properties.
- In terms of mechanical properties, ZA 8 has the highest creep strength among all zinc alloys. And it is the highest strength alloy among all hot chamber die-cast zinc alloys.
ZA-12 is the best gravity casting alloy for sand molds, permanent molds, and graphite molds. It is also a high-quality (cold chamber) die casting alloy. ZA-12 often competes with ZA-27 in strength applications. ZA-12 is an excellent bearing alloy. Although the coating adhesion is reduced compared with the traditional zinc alloy, it is also plateable.
ZA-27 or zinc-aluminum alloy contains more aluminum than Zamak combination gold. The number 27 represents the approximate percentage of aluminum.
- ZA-27 has the highest aluminum content, the highest strength, the highest melting point, and the lowest ZA group density.
- This zinc alloy has excellent bearing performance and can be designed as castings for certain applications.
- Its higher casting temperature requires a cold chamber process.
Zinc Die Casting Application
Intricate reticulated zinc housing with precise thin walls, providing excellent electrical performance and shielding performance.
Our proprietary multi-slide die-casting process and excellent thin-wall capability make us the premier supplier of zinc components in various consumer electronic equipment.
The castability, wear-resistance, and structural integrity of zinc alloy make it ideal for highly complex shapes in the automotive safety and electronics industries.