Overview of Zinc Alloys

Alloys Tailored to meet your needs: General Purpose and Special High Strength Alloys.

ZAMAK alloys are the standard general purpose zinc die casting alloys, exhibiting an excellent combination of cost, strength, ductility, impact strength and finishing characteristics. They are the designer's first choice when considering die casting.

ZA alloys are the family of new high strength zinc-aluminum engineering materials. They exhibit the highest yield strengths of all conventionally die cast materials and have superior high temperature performance compared to the ZAMAK alloys. They also offer bearing and wear characteristics superior to conventional bronze bearing.

While the ZAMAK alloys are mainly die casting alloys, the entire ZA family can be used for sand, permanent mold and die casting, as well as in centrifugal, investment, plaster, and continuous casting.

The ZA alloys mainly in terms of their higher aluminum content. The numerical digits (8, 12 and 27) represent their respective approximate weight percentages of aluminum.

ZA alloys are specialty materials and therefore are not as universally available as the ZAMAK alloys. When die cast, only ZA-8 can be "hot-chamber" cast which is the most cost effective and flexible die casting process. ZA-12 and ZA-27 must be "cold chamber" die cast similar to aluminum alloys.

Major Alloy Characteristics

ZAMAK 2: This is the strongest and hardest ZAMAK alloy. Generally die cast, it is occasionally employed for gravity casting. ZAMAK 2 is not the widely used.

ZAMAK 3: This is the most used general purpose zinc die casting alloy, providing an excellent combination of strength, ductility and impact strength. It also provides excellent plating and finishing characteristics. This alloy is the designer's first choice for die casting applications.

ZAMAK 5: ZAMAK 5 should be considered when moderately greater hardness, strength and creep resistance over ZAMAK 3 is required.

ZAMAK 7: this is a high purity for of ZAMAK 3 with similar mechanical properties. However, ZAMAK 7 has higher ductility (for forming bending operations) and the highest casting fluidity of the ZAMAK family.

ZA-8: This should be the first choice when considering die casting the ZA family, due to its cost effective hot chamber castability. ZA-8 provides improved performance characteristics over the ZAMAK alloys. Plating and finishing characteristics are similar. ZA-8 can also be sand or permanent mold cast.

ZA-12: This is the preferred alloy for permanent mold applications, although it can also be cal-chamber die cast with excellent results. It combines low temperature melting efficiency and thin wall capabilities with premium mechanical properties. ZA-12 should be used when switching from cast iron or permanent molded aluminum. ZA-21 can usually be poured directly into molds designed for aluminum and brass.

ZA-27: Components requiring optimum strength, hardness and light weight should be specified using ZA-27. With over double the yield strength of die cast A380 aluminum and 25% lighter than ZAMAK 3, this is definitely the high performance member of the group. ZA-27 also offers excellent bearing properties, comparable to those of aluminum-bronze.

EZAC:  Eastern Alloy's newest commercially available alloy.  EZAC is the strongest, hardest and most creep resistant die casting alloy available, and can be cast in the "hot-chamber" die casting process.

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