Technological Advances in Zinc Die Casting DRIVING improvements in Quality, Performance and Carbon Reduction.

A Quick Refresher on Zinc Properties:

Let’s first review the advantages of die casting in zinc. At room temperature, zinc die casting alloys have the highest yield, hardness, impact strength, elongation, thermal and electrical conductivity of all the die casting alloys. These mechanical properties make zinc alloys an excellent choice for products across a wide spectrum of end uses. On the processing side, zinc alloys have the lowest melting temperature (other than lead), the lowest heat capacity and the highest fluidity. These physical properties allow for casting thinner walls and more complex shapes, faster cycle times with a far longer die life than competing die casting alloys. The combination of the inherent corrosion protection of zinc, the properties of zinc alloys and the speed and flexibility of the die casting process provides a significant advantage.

Zinc does have some challenges.  Due to zinc’s lower melting temperature, zinc die casting alloys should be considered for applications at room temperature, or higher temperatures when no stress is applied.  Although zinc has a higher density, it is still lighter than steel, sintered iron, and other non-ferrous alloys such as bronze, brass, lead alloys, etc.  However, this weight penalty is frequently compensated by the ability to cast thinner walls and more complex shapes.

To learn more about zinc die casting’s advantages, please visit other IZA resources including:

https://diecasting.zinc.org/advantages/

https://diecasting.zinc.org/characteristics/

https://diecasting.zinc.org/castingstudy/

New Advancements in Zinc Die Casting:

Exciting new developments in the zinc die casting industry can be used to further enhance the quality and performance of die cast components while at the same time lowering cost and environmental impact.  The following are examples of this technology:

Hot Runner Systems

Hot runner systems have been in use in the plastics industry for over 30 years; However, implementing this technology in the metals industry has been much more challenging… until recently!  Hot runner systems in zinc are now available in most conventional die casting machines, providing substantial process advantages over conventional die casting methods.

Using the hot runner systems eliminates the sprue and runner system, which allows for several processing advantages including higher capacity (more cavities), faster cycle times, lower processing scrap, better quality (no air in the process and better temperature control), and even a lower carbon footprint.

Advancements in Gooseneck technology:

A die casting “gooseneck” is a pump that is immersed in the molten zinc that feeds the die in the Hot Chamber die Casting Process.  The hot chamber process is an advantage over the Cold Chamber process because it is more efficient with less air and faster cycle times.  Recent advancements in gooseneck technology have further improved this highly efficient process.

In the standard die casting process, a plunger pushes molten zinc through the gooseneck and nozzle during a “slow stroke” process.  This allows venting of existing air through the die until the metal front reaches the gate of the cavity at which point a fast shot begins and fills the cavity at the proper velocity and fill time.  The new FDS “Frech Dosing System” comprises of a new valve system in the gooseneck which effectively keeps the gooseneck filled with molten zinc alloy.

The advantage of keeping the molten zinc alloy close to the gate is that it removes the air in the casting process, thus helping eliminate or at least substantially reducing the potential of gas porosity.  Improvements in quality and performance can be achieved.

To Learn More:

For further information regarding these technologies, please visit:

Hot Runner Systems:  https://www.youtube.com/watch?v=EaD-98gB3aw

Gooseneck Technology:  https://www.youtube.com/watch?v=6ws5-63p3jo