Know Your Zinc Alloys – A Definitive Guide
To understand the quality of our zinc alloys, let us tell you about our selection as well as some of the qualities of both ZAMAK Alloys and our own ZA alloys.
ZAMAK alloys are usually a designer’s first choice for the purpose of die casting. Most of these ZAMAK alloy products display an excellent combination of strength, ductility, and impact strength at a reasonable production cost.
However there is also a higher quality zinc alloy we make called ZA alloys. This is a family of high quality and high strength zinc-aluminum engineering materials that differ greatly from the ZAMAK alloys. ZA alloys have a yield strength that’s higher than most other die cast materials, and they also perform much better under high temperatures compared to the ZAMAK alloys.
ZAMAK alloys are primarily used for die casting, but ZA alloys can be used for this purpose as well as for sand and permanent mold casting too, which ZAMAK alloys cannot be used for. ZA alloys have also been used in centrifugal, investment, plaster, and continuous casting.
The alloys we’re about to talk about below are specified by their approximate weight percentage of aluminum like 8, 12, or 27.
You see, ZA alloys are specialty materials that aren’t as widely available as ZAMAK alloys, which is why they’re the standard. This is primarily due to whether you need to use “hot-chamber” or “cold chamber” die casting methods. ZA-8 for instance can be used for hot chamber casting, the most cost effective and flexible process, while ZA-12 and ZA-27 must use cold chamber die casting like aluminum alloys do.
Here’s the major characteristics of the zinc alloys we use.
Overview of Alloy Characteristics
ZAMAK 2: It’s not the most widely used, but it is the strongest of the ZAMAK alloy family. It’s generally die cast, and is occasionally used in gravity casting.
ZAMAK 3: This one is the most widely used zinc die casting alloy because it has the best blend of strength, ductility, impact strength characteristics. It’s usually the designer’s first choice for die casting applications.
ZAMAK 5: This alloy is very similar to ZAMAK 3, but has a moderately greater hardness, strength, and creep resistance, which makes it essential when you need this combination of factors.
ZAMAK 7: Think of this one as a higher purity ZAMAK 3 with similar mechanical properties, although it has higher ductility (for forming bending operations) as well as the highest casting fluidity of the ZAMAK family.
ZA-8: Since hot chamber casting is the most widely used, this should be the first choice among the ZA family because of it’s great cost effectiveness. Its performance characteristics are much better than those of the ZAMAK alloys, although its plating and finishing characteristics are similar. This alloy can also be used as a sand or permanent mold cast.
ZA-12: This one is the best alloy for permanent mold applications, but it can also be cal-chamber die cast with amazing results too. The most important characteristic of ZA-12 is its combination of low temperature melting efficiency and thin wall capabilities with premium mechanical properties. This alloy should be used when switching from cast iron or permanent molded aluminum, and it can be poured directly into molds designed for aluminum or brass.
ZA-27: Definitely the high performance member of the group as it’s ideal for any components that require optimum strength, hardness, and light weight. This is because it has double the yield strength of die cast A380 aluminum and it’s 25% lighter than ZAMAK 3. It also has bearing properties comparable to those of aluminum-bronze.
EZAC: This is our newest commercially available zinc alloy. EZAC is the strongest, hardest, and most creep resistant die casting alloy available. Plus it can be used in the “hot-chamber” die casting process.
Contact us for more information
If you are unsure which alloy is best for your project, don’t worry. We have many years experience working with a huge variety of projects. Just send us an email, or leave a comment in the box below.